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  • 1. Alsafi, Zahraa
    et al.
    Malmgren, Andreas
    Gudmundsson, Petri
    Malmö högskola, Faculty of Health and Society (HS), Department of Biomedical Science (BMV).
    Stagmo, Martin
    Dencker, Martin
    Myocardial performance index in female athletes.2017In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 15, article id 20Article in journal (Refereed)
    Abstract [en]

    Background: Long-term intensive training leads to morphological and mechanical changes in the heart generally known as “athlete’s heart”. Previous studies have suggested that the diastolic and systolic function of the ventricles is unaltered in athletes compared to sedentary. The purpose of this study was to investigate myocardial performance index (MPI) by pulsed wave Doppler (PWD) and by tissue Doppler imaging (TDI) in female elite athletes compared to sedentary controls. Methods: The study consisted of 32 athletes (mean age 20 ± 2 years) and 34 sedentary controls (mean age 23 ± 2 years). MPI by PWD and TDI were measured in the left (LV) and right ventricle (RV) in both groups. Moreover, comparisons of MPI by the two methods and between the LV and RV within the two groups were made. Results: There were no significant differences in MPI between athletes and controls (p > 0.05), whereas the LV had significantly higher MPI compared to RV (p < 0.001, in athletes and controls). The agreement and the correlation between the two methods measuring MPI showed low agreement and no correlation (athletes RV r = −0.027, LV r = 0.12; controls RV r = 0.20, LV r = 0.30). Conclusion: The global function of the LV and RV measured by MPI with PWD and TDI is similar in female athletes compared to sedentary controls. Conversely, both MPI by PWD and by TDI shows a significant difference between the LV and RV. However, the agreement and correlation between conventional methods of measuring MPI by PWD compared to MPI by TDI is very poor in both these populations.

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  • 2.
    A'Roch, Roman
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Gustafsson, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Poelaert, Jan
    Anesthesiology, University of Brussels, Belgium.
    Haney, Michael
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Left ventricular strain and peak systolic velocity: responses to controlled changes in load and contractility, explored in a porcine model2012In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 10, no 1, article id 22Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Tissue velocity echocardiography is increasingly used to evaluate global and regional cardiac function. Previous studies have suggested that the quantitative measurements obtained during ejection are reliable indices of contractility, though their load-sensitivity has been studied in different settings, but still remains a matter of controversy. We sought to characterize the effects of acute load change (both preload and afterload) and change in inotropic state on peak systolic velocity and strain as a measure of LV contractility.

    METHODS: Thirteen anesthetized juvenile pigs were studied, using direct measurement of left ventricular pressure and volume and transthoracic echocardiography. Transient inflation of a vena cava balloon catheter produced controlled load alterations. At least eight consecutive beats in the sequence were analyzed with tissue velocity echocardiography during the load alteration and analyzed for change in peak systolic velocities and strain during same contractile status with a controlled load alteration. Two pharmacological inotropic interventions were also included to generate several myocardial contractile conditions in each animal.

    RESULTS: Peak systolic velocities reflected the drug-induced changes in contractility in both radial and longitudinal axis. During the acute load change, the peak systolic velocities remain stable when derived from signal in the longitudinal axis and from the radial axis. The peak systolic velocity parameter demonstrated no strong relation to either load or inotropic intervention, that is, it remained unchanged when load was systematically and progressively varied (peak systolic velocity, longitudinal axis, control group beat 1- 5.72 +/- 1.36 with beat 8- 6.49 +/- 1.28 cm/sec, 95% confidence interval), with the single exception of the negative inotropic intervention group where peak systolic velocity decreased a small amount during load reduction (beat 1- 3.98 +/- 0.92 with beat 8- 2.72 +/- 0.89 cm/sec). Systolic strain, however, showed a clear degree of load-dependence.

    CONCLUSIONS: Peak systolic velocity appears to be load-independent as tested by beat-to-beat load reduction, while peak systolic strain appears to be load-dependent in this model. Peak systolic velocity, in a controlled experimental model where successive beats during load alteration are assessed, has a strong relation to contractility. Peak systolic velocity, but not peak strain rate, is largely independent of load, in this model. More study is needed to confirm this finding in the clinical setting.

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  • 3.
    A'Roch, Roman
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Gustafsson, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Poelaert, Jan
    Anesthesiology, University of Brussels, Belgium.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Haney, Michael
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Left ventricular twist is load-dependent as shown in a large animal model with controlled cardiac load2012In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 10, article id 26Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Left ventricular rotation and twist can be assessed noninvasively by speckle tracking echocardiography. We sought to characterize the effects of acute load change and change in inotropic state on rotation parameters as a measure of left ventricular (LV) contractility.

    METHODS: Seven anesthetised juvenile pigs were studied, using direct measurement of left ventricular pressure and volume and simultaneous transthoracic echocardiography. Transient inflation of an inferior vena cava balloon (IVCB) catheter produced controlled load reduction. First and last beats in the sequence of eight were analysed with speckle tracking (STE) during the load alteration and analysed for change in rotation/twist during controlled load alteration at same contractile status. Two pharmacological inotropic interventions were also included to examine the same hypothesis in additionally conditions of increased and decreased myocardial contractility in each animal. Paired comparisons were made for different load states using the Wilcoxon's Signed Rank test.

    RESULTS: The inferior vena cava balloon occlusion (IVCBO) load change compared for first to last beat resulted in LV twist increase (11.67degrees +/-2.65degrees vs. 16.17degrees +/-3.56degrees respectively, p < 0.004) during the load alteration and under adrenaline stimulation LV twist increase 12.56degrees +/-5.1degrees vs. 16.57degrees +/-4.6degrees (p < 0.013), and though increased, didn't reach significance in negative inotropic condition. Untwisting rate increased significantly at baseline from 41.7degrees/s +/-41.6degrees/s vs.122.6degrees/s +/-55.8degrees/s (P < 0.039) and under adrenaline stimulation untwisting rate increased (55.3degrees/s +/-3.8degrees/s vs.111.4degrees/s +/-24.0degrees/s (p < 0.05), but did not systematically changed in negative inotropic condition.

    CONCLUSIONS: Peak systolic LV twist and peak early diastolic untwisting rate are load dependent. Differences in LV load should be included in the interpretation when serial measures of twist are compared.

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  • 4.
    Bajraktari, Gani
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Batalli, Arlind
    Poniku, Afrim
    Ahmeti, Artan
    Olloni, Rozafa
    Hyseni, Violeta
    Vela, Zana
    Morina, Besim
    Tafarshiku, Rina
    Vela, Driton
    Rashiti, Premtim
    Haliti, Edmond
    Henein, Michael Y
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Left ventricular markers of global dyssynchrony predict limited exercise capacity in heart failure, but not in patients with preserved ejection fraction2012In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 10, p. 36-Article in journal (Refereed)
    Abstract [en]

    Background: The aim of this study was to prospectively examine echocardiographic parameters that correlate and predict functional capacity assessed by 6 min walk test (6-MWT) in patients with heart failure (HF), irrespective of ejection fraction (EF).

    Methods: In 147 HF patients (mean age 61 +/- 11 years, 50.3% male), a 6-MWT and an echo-Doppler study were performed in the same day. Global LV dyssynchrony was indirectly assessed by total isovolumic time - t-IVT [in s/min; calculated as: 60 - (total ejection time + total filling time)], and Tei index (t-IVT/ejection time). Patients were divided into two groups based on the 6-MWT distance (Group I: <= 300 m and Group II: > 300 m), and also in two groups according to EF (Group A: LVEF >= 45% and Group B: LVEF <45%).

    Results: In the cohort of patients as a whole, the 6-MWT correlated with t-IVT (r = -0.49, p < 0.001) and Tei index (r = -0.43, p < 0.001) but not with any of the other clinical or echocardiographic parameters. Group I had lower hemoglobin level (p = 0.02), lower EF (p = 0.003), larger left atrium (p = 0.02), thicker interventricular septum (p = 0.02), lower A wave (p = 0.01) and lateral wall late diastolic myocardial velocity a' (p = 0.047), longer isovolumic relaxation time (r = 0.003) and longer t-IVT (p = 0.03), compared with Group II. In the patients cohort as a whole, only t-IVT ratio [1.257 (1.071-1.476), p = 0.005], LV EF [0.947 (0.903-0.993), p = 0.02], and E/A ratio [0.553 (0.315-0.972), p = 0.04] independently predicted poor 6-MWT performance (< 300 m) in multivariate analysis. None of the echocardiographic measurements predicted exercise tolerance in HFpEF.

    Conclusion: In patients with HF, the limited exercise capacity, assessed by 6-MWT, is related mostly to severity of global LV dyssynchrony, more than EF or raised filling pressures. The lack of exercise predictors in HFpEF reflects its multifactorial pathophysiology.

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    Left ventricular markers of global dyssynchrony predict limited exercise capacity in heart failure, but not in patients with preserved ejection fraction
  • 5. Batalli, Arlind
    et al.
    Ibrahimi, Pranvera
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology. Clinic of Cardiology, University Clinical Centre of Kosova, "Rrethi i Spitalit", p.n., Prishtina, Kosovo.
    Bytyçi, Ibadete
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Medicine.
    Ahmeti, Artan
    Haliti, Edmond
    Elezi, Shpend
    Henein, Michael Y
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology. Molecular and Clinical Sciences Research Institute, St George University London, London, United Kingdom.
    Bajraktari, Gani
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology. Clinic of Cardiology, University Clinical Centre of Kosova, “Rrethi i Spitalit”, p.n., Prishtina, Kosovo; Medical Faculty, University of Prishtina, Prishtina, Kosovo.
    Different determinants of exercise capacity in HFpEF compared to HFrEF2017In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 15, no 1, article id 12Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Quality of life is as important as survival in heart failure (HF) patients. Controversies exist with regards to echocardiographic determinants of exercise capacity in HF, particularly in patients with preserved ejection fraction (HFpEF). The aim of this study was to prospectively examine echocardiographic parameters that correlate and predict functional exercise capacity assessed by 6 min walk test (6-MWT) in patients with HFpEF.

    METHODS: In 111 HF patients (mean age 63 ± 10 years, 47% female), an echo-Doppler study and a 6-MWT were performed in the same day. Patients were divided into two groups based on the 6-MWT distance (Group I: ≤ 300 m and Group II: >300 m).

    RESULTS: Group I were older (p = 0.008), had higher prevalence of diabetes (p = 0.027), higher baseline heart rate (p = 0.004), larger left atrium - LA (p = 0.001), longer LV filling time - FT (p = 0.019), shorter isovolumic relaxation time (p = 0.037), shorter pulmonary artery acceleration time - PA acceleration time (p = 0.006), lower left atrial lateral wall myocardial velocity (a') (p = 0.018) and lower septal systolic myocardial velocity (s') (p = 0.023), compared with Group II. Patients with HF and reduced EF (HFrEF) had lower hemoglobin (p = 0.007), higher baseline heart rate (p = 0.005), higher NT-ProBNP (p = 0.001), larger LA (p = 0.004), lower septal s', e', a' waves, and septal mitral annular plane systolic excursion (MAPSE), shorter PA acceleration time (p < 0.001 for all), lower lateral MAPSE, higher E/A & E/e', and shorter LVFT (p = 0.001 for all), lower lateral e' (p = 0.009), s' (p = 0.006), right ventricular e' and LA emptying fraction (p = 0.012 for both), compared with HFpEF patients. In multivariate analysis, only LA diameter [2.676 (1.242-5.766), p = 0.012], and diabetes [0.274 (0.084-0.898), p = 0.033] independently predicted poor 6-MWT performance in the group as a whole. In HFrEF, age [1.073 (1.012-1.137), p = 0.018] and LA diameter [3.685 (1.348-10.071), p = 0.011], but in HFpEF, lateral s' [0.295 (0.099-0.882), p = 0.029], and hemoglobin level [0.497 (0.248-0.998), p = 0.049] independently predicted poor 6-MWT performance.

    CONCLUSIONS: In HF patients determinants of exercise capacity differ according to severity of overall LV systolic function, with left atrial enlargement in HFrEF and longitudinal systolic shortening in HFpEF as the the main determinants.

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  • 6. Bergenzaun, Lill
    et al.
    Öhlin, Hans
    Gudmundsson, Petri
    Malmö högskola, Faculty of Health and Society (HS), Department of Biomedical Science (BMV).
    Willenheimer, Ronnie
    Chew, Michelle
    Mitral annular plane systolic excursion (MAPSE) in shock: a valuable echocardiographic parameter in intensive care patients: Cardiovascular Ultrasound2013In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 11, no 16, article id 16Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Assessing left ventricular (LV) dysfunction by echocardiography in ICU patients is common. The aim of this study was to investigate mitral annular plane systolic excursion (MAPSE) in critically ill patients with shock and its relation to LV systolic and diastolic function, myocardial injury and to outcome. METHODS: In a prospective, observational, cohort study we enrolled 50 patients with SIRS and shock despite fluid resuscitation. Transthoracic echocardiography (TTE) measuring LV function was performed within 12 hours after admission and daily for a 7-day observation period. TTE and laboratory measurements were related to 28-day mortality. RESULTS: MAPSE on day 1 correlated significantly with LV ejection fraction (LVEF), tissue Doppler indices of LV diastolic function (é, E/é) and high-sensitive troponin T (hsTNT) (p< 0.001, p= 0.039, p= 0.009, p= 0.003 respectively) whereas LVEF did not correlate significantly with any marker of LV diastolic function or myocardial injury. Compared to survivors, non-survivors had a significantly lower MAPSE (8 [IQR 7.5-11] versus 11 [IQR 8.9-13] mm; p= 0.028). Other univariate predictors were age (p=0.033), hsTNT (p=0.014) and Sequential Organ Failure Assessment (SOFA) scores (p=0.007). By multivariate analysis MAPSE (OR 0.6 (95% CI 0.5- 0.9), p= 0.015) and SOFA score (OR 1.6 (95% CI 1.1- 2.3), p= 0.018) were identified as independent predictors of mortality. Daily measurements showed that MAPSE, as sole echocardiographic marker, was significantly lower in most days in non-survivors (p<0.05 at day 1-2, 4-6). CONCLUSIONS: MAPSE seemed to reflect LV systolic and diastolic function as well as myocardial injury in critically ill patients with shock. The combination of MAPSE and SOFA added to the predictive value for 28-day mortality.

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  • 7.
    Chew, Michelle
    Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Anaesthesiology and Intensive Care in Linköping.
    Mitral annular plane systolic excursion (MAPSE) in shock: a valuable echocardiographic parameter in intensive care patients2013In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 1, no 16Article in journal (Refereed)
    Abstract [en]

    Background

    Assessing left ventricular (LV) dysfunction by echocardiography in ICU patients is common. The aim of this study was to investigate mitral annular plane systolic excursion (MAPSE) in critically ill patients with shock and its relation to LV systolic and diastolic function, myocardial injury and to outcome.

    Methods

    In a prospective, observational, cohort study we enrolled 50 patients with SIRS and shock despite fluid resuscitation. Transthoracic echocardiography (TTE) measuring LV function was performed within 12 hours after admission and daily for a 7-day observation period. TTE and laboratory measurements were related to 28-day mortality.

    Results

    MAPSE on day 1 correlated significantly with LV ejection fraction (LVEF), tissue Doppler indices of LV diastolic function (é, E/é) and high-sensitive troponin T (hsTNT) (p< 0.001, p= 0.039, p= 0.009, p= 0.003 respectively) whereas LVEF did not correlate significantly with any marker of LV diastolic function or myocardial injury. Compared to survivors, non-survivors had a significantly lower MAPSE (8 [IQR 7.5-11] versus 11 [IQR 8.9-13] mm; p= 0.028). Other univariate predictors were age (p=0.033), hsTNT (p=0.014) and Sequential Organ Failure Assessment (SOFA) scores (p=0.007). By multivariate analysis MAPSE (OR 0.6 (95% CI 0.5- 0.9), p= 0.015) and SOFA score (OR 1.6 (95% CI 1.1- 2.3), p= 0.018) were identified as independent predictors of mortality. Daily measurements showed that MAPSE, as sole echocardiographic marker, was significantly lower in most days in non-survivors (p<0.05 at day 1–2, 4–6).

    Conclusions

    MAPSE seemed to reflect LV systolic and diastolic function as well as myocardial injury in critically ill patients with shock. The combination of MAPSE and SOFA added to the predictive value for 28-day mortality.

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  • 8. Dalla, Keti
    et al.
    Hallman, Caroline
    Bech-Hanssen, Odd
    Haney, Michael
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Ricksten, Sven-Erik
    Strain echocardiography identifies impaired longitudinal systolic function in patients with septic shock and preserved ejection fraction2015In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 13, article id 30Article in journal (Refereed)
    Abstract [en]

    Background: Myocardial dysfunction is recognized in sepsis. We hypothesized that mechanical left (LV) and right (RV) ventricular function analysed using 2-dimensional speckle-tracking echocardiography in a cohort of early severe sepsis or septic shock patients, would be different to that of a group of critically ill, non-septic patients.

    Methods: Critically ill adult patients with early, severe sepsis/septic shock (n = 48) and major trauma patients with no sepsis (n = 24) were included retrospectively, as well as healthy controls (n = 16). Standard echocardiographic examinations, including right (RV) left (LV) volumes and mitral, aortic and pulmonary vein Doppler flow profiles, were retrospectively identified and the studies were then reanalysed for assessment of myocardial strain using speckle-tracking echocardiography. Endocardial tracing of the LV was performed in apical four-chamber (4-Ch), two-chamber (2-Ch), apical long-axis (3-Ch) and apical views of RV determining the longitudinal LV and RV free wall strain in each subject.

    Results: In septic patients, heart rate was significantly higher (p = 0.009) and systolic (p < 0.001) and mean arterial pressures (p < 0.001), as well as systemic vascular resistance (p < 0.001) were significantly lower when compared to the non-septic trauma group. Ninety-three per cent of the septic patients and 50 % of the trauma patients were treated with norepinephrine (p < 0.001). LV ejection fraction (LVEF) was lower in the septic patients (p = 0.019). In septic patients with preserved LVEF (>50 %, n = 34), seventeen patients (50 %) had a depressed LV global longitudinal function, defined as a LV global strain > -15 %, compared to two patients (8.7 %) in the non-septic group (p = 0.0014). In septic patients with preserved LVEF, LV global and RV free wall strain were 14 % (p = 0.014) and 17 % lower (p = 0.008), respectively, compared to the non-septic group with preserved LVEF. There were no significant differences between groups with respect to LV end-diastolic or end-systolic volumes, stroke volume, or cardiac output. There were no signs of diastolic dysfunction from the mitral or pulmonary vein Doppler profiles in the septic patients.

    Conclusions: LV and RV systolic function is impaired in critically ill patients with early septic shock and preserved LVEF, as detected by Speckle-tracking 2D echocardiography. Strain imaging may be useful in the early detection of myocardial dysfunction in sepsis.

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  • 9.
    de Geer, Lina
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Anaesthesiology and Intensive Care in Linköping.
    Oscarsson, Anna
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Anaesthesiology and Intensive Care in Linköping.
    Engvall, Jan
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Variability in echocardiographic measurements of left ventricular function in septic shock patients2015In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 13, no 1, p. 19-Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Echocardiography is increasingly used for haemodynamic evaluation and titration of therapy in intensive care, warranting reliable and reproducible measurements. The aim of this study was to evaluate the observer dependence of echocardiographic findings of left ventricular (LV) diastolic and systolic dysfunction in patients with septic shock.

    METHODS: Echocardiograms performed in 47 adult patients admitted with septic shock to a general intensive care unit (ICU) were independently evaluated by one cardiologist and one intensivist for the following signs: decreased diastolic tissue velocity of the base of the LV septum (e), increased early mitral inflow (E) to e ratio (E/e), decreased LV ejection fraction (EF) and decreased LV global longitudinal peak strain (GLPS). Diastolic dysfunction was defined as e <8.0cm/s and/or E/e [greater than or equal to]15 and systolic dysfunction as EF <50% and/or GLPS>15%. Ten randomly selected examinations were re-analysed two months later. Pearson’s r was used to test the correlation and Bland-Altman plots to assess the agreement between observers. Kappa statistics were used to test the consistency between readers and intraclass correlation coefficients (ICC) for inter- and intraobserver variability.

    RESULTS: In 44 patients (94%), image quality was sufficient for echocardiographic measurements. The agreement between observers was moderate (k=0.60 for e, k=0.50 for E/e and k=0.60 for EF) to good (k=0.71 for GLPS). Pearson’s r was 0.76 for e, 0.85 for E/e, 0.78 for EF and 0.84 for GLPS (p<0.001 for all four). The ICC between observers for e was very good (0.85; 95% confidence interval (CI) 0.73-0.92), good for E/e (0.70; 95% CI 0.45 - 0.84), very good for EF (0.87; 95% CI 0.77 - 0.93), excellent for GLPS (0.91; 95% CI 0.74 - 0.95), and very good for all measures repeated by one of the observers. On Bland-Altman analysis, the mean differences and 95% limits of agreement for e, E/e, EF and GLPS were 0.01 (0.04 - 0.07), 2.0 (14.2 - 18.1), 0.86 (16 - 14.3) and 0.04 (5.04 - 5.12), respectively.

    CONCLUSIONS: Moderate observer-related differences in assessing LV dysfunction were seen. GLPS is the least user dependent and most reproducible echocardiographic measurement of LV function in septic shock.

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  • 10.
    Elmstedt, Nina
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Ferm-Widlund, Kjerstin
    Lind, Britta
    KTH, School of Technology and Health (STH), Medical Engineering.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Westgren, Magnus
    Fetal cardiac muscle contractility decreases with gestational age: a color-coded tissue velocity imaging study2012In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 10, p. 19-Article in journal (Refereed)
    Abstract [en]

    Background: Present data regarding how the fetal heart works and develops throughout gestation is limited. However, the possibility to analyze the myocardial velocity profile provides new possibilities to gain further knowledge in this area. Thus, the objective of this study was to evaluate human fetal myocardial characteristics and deformation properties using color-coded tissue velocity imaging (TVI). Methods: TVI recordings from 55 healthy fetuses, at 18 to 42 weeks of gestation, were acquired at a frame rate of 201-273 frames/s for offline analysis using software enabling retrieval of the myocardial velocity curve and 2D anatomical information. The measurements were taken from an apical four-chamber view, and the acquired data was correlated using regression analysis. Results: Left ventricular length and width increased uniformly with gestational age. Atrioventricular plane displacement and the E'/A' ratio also increased with gestational age, while a longitudinal shortening was demonstrated. Conclusions: Fetal cardiac muscle contractility decreases with gestational age. As numerous fetal-and pregnancy-associated conditions directly influence the pumping function of the fetal heart, we believe that this new insight into the physiology of the human fetal cardiovascular system could contribute to make diagnosis and risk assessment easier and more accurate.

  • 11.
    Elmstedt, Nina
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering.
    Lind, Britta
    KTH, School of Technology and Health (STH), Medical Engineering.
    Ferm-Widlund, Kjerstin
    CFM, Karolinska Universitetssjukhuset.
    Westgren, Magnus
    CFM, Karolinska Universitetssjukhuset.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Reference values for fetal tissue velocity imaging and a new approach to evaluate fetal myocardial function2013In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 11, no 1, p. 29-Article in journal (Refereed)
    Abstract [en]

    Objectives: Myocardial function can be evaluated using color-coded tissue velocity imaging (TVI) to analyze the longitudinal myocardial velocity profile, and by expressing the motion of the atrioventricular plane during a cardiac cycle as coordinated events in the cardiac state diagram (CSD). The objective of this study was to establish gestational age specific reference values for fetal TVI measurements and to introduce the CSD as a potential aid in fetal myocardial evaluation. Methods: TVI recordings from 125 healthy fetuses, at 18 to 42 weeks of gestation, were performed with the transducer perpendicular to the apex to provide a four-chamber view. The myocardial velocity data was extracted from the basal segment of septum as well as the left and right ventricular free wall for subsequent offline analysis. Results: During a cardiac cycle the longitudinal peak velocities of septum increased with gestational age, as did the peak velocities of the left and right ventricular free wall, except for the peak velocity of post ejection. The duration of rapid filling and atrial contraction increased during pregnancy while the duration of post ejection decreased. The duration of pre ejection and ventricular ejection did not change significantly with gestational age. Conclusion: Evaluating fetal systolic and diastolic performance using TVI together with CSD could contribute to increase the knowledge and understanding of fetal myocardial function and dysfunction. The pre and post ejection phases are the variables most likely to indicate fetuses with abnormal myocardial function.

  • 12.
    Engvall, Jan
    et al.
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Diagnostics and Specialist Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart Center, Department of Clinical Physiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Åström, Meriam
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Diagnostics and Specialist Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart Center, Department of Clinical Physiology in Linköping.
    Nylander, Eva
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Diagnostics and Specialist Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart Center, Department of Clinical Physiology in Linköping.
    Brudin, Lars
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Diagnostics and Specialist Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Maret, Eva
    Karolinska Inst, Sweden; Karolinska Univ Hosp, Sweden.
    Moderately trained male football players, compared to sedentary male adults, exhibit anatomical but not functional cardiac remodelling, a cross-sectional study2021In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 19, article id 36Article in journal (Refereed)
    Abstract [en]

    Background Elite athletes have been the subject of great interest, but athletes at an intermediate level of physical activity have received less attention in respect to the presence of cardiac enlargement and/or hypertrophy. We hypothesized that playing football, often defined as demanding less endurance components than running or cycling, would still induce remodelling similar to sports with a dominating endurance component. Methods 23 male football players, age 25+/- 3.9 yrs. underwent exercise testing, 2D- and 3D- echocardiography and cardiac magnetic resonance (CMR). The results were compared with a control group of engineering students of similar age. The athletes exercised 12 h/week and the control subjects 1 h/week, p &lt; 0.001. Results The football players achieved a significantly higher maximal load at the exercise test (380 W vs 300 W, p &lt; 0.001) as well as higher calculated maximal oxygen consumption, (49.7 vs 37.4 mL x kg(- 1) x min(- 1), p &lt; 0.001) compared to the sedentary group. All left ventricular (LV) volumes assessed by 3DEcho and CMR, as well as CMR left atrial (LA) volume were significantly higher in the athletes (3D-LVEDV 200 vs 154 mL, CMR-LVEDV 229 vs 185 mL, CMR-LA volume 100 vs 89 mL, p &lt; 0.001, p = 0.002 and p = 0.009 respectively). LVEF and RVEF, LV strain by CMR or by echo did not differentiate athletes from sedentary participants. Right ventricular (RV) longitudinal strain, LA and right atrial (RA) strain by CMR all showed similar results in the two groups. Conclusion Moderately trained intermediate level football players showed anatomical but not functional cardiac remodelling compared to sedentary males.

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  • 13.
    Gottfridsson, Peter
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    A’Roch, Roman
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Lindqvist, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Law, Lucy
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Myrberg, Tomi
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Hultin, Magnus
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    A'Roch, Alexander
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Haney, Michael
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Left atrial contraction strain and controlled preload alterations, a study in healthy individuals2022In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 20, no 1, article id 8Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: In order to assess left atrial contractile function in disturbed circulatory conditions, it is necessary to have a clear understanding of how it behaves in a normal resting state with changes in loading conditions. However, currently the understanding of this relationship is incomplete. We hypothesize that in healthy individuals, left atrial contraction strain and its peak strain rate are increased or decreased by increasing or decreasing preload, respectively.

    METHODS: Controlled maneuvers used to change preload included continuous positive airway pressure by mask (CPAP 20 cmH2O) for preload decrease, and passive leg raise (15 degrees angle) for preload increase. Cardiac ultrasound 4-chamber views of the left atria and left ventricle were acquired at baseline and during maneuver. Acquired images were post processed and analyzed offline. Comparisons were made using paired t-test and means with 95% confidence interval.

    RESULTS: There were 38 participants, complete results were obtained from 23 in the CPAP maneuver and 27 in the passive leg raise maneuver. For the CPAP group, left atrial contraction strain was 11.6% (10.1 to 13.1) at baseline and 12.8% (11.0 to 14.6) during the maneuver (p = 0.16). Left atrial contraction peak strain rate was - 1.7 s- 1 (- 1.8 to - 1.5) at baseline and - 1.8 s- 1 (- 2.0 to - 1.6) during the maneuver (p = 0.29). For the passive leg raise-group, left atrial contraction strain was 10.1% (9.0 to 11.2) at baseline and 10.8% (9.4 to 12.3) during the maneuver (p = 0.28). Left atrial contraction peak strain rate was - 1.5 s- 1 (- 1.6 to - 1.4) at baseline and - 1.6 s- 1 (- 1.8 to - 1.5) during the maneuver (p = 0.29). Left atrial area, an indicator of preload, increased significantly during passive leg raise and decreased during CPAP.

    CONCLUSION: In healthy individuals, left atrial contraction strain and its peak strain rate seem to be preload-independent.

    TRIAL REGISTRATION: The study was 2018-02-19 registered at clinicaltrials.gov ( NCT03436030 ).

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  • 14.
    Govind, Satish C.
    et al.
    Bhagwan Mahavir Jain Heart Center, Bangalore, India.
    Roumina, S.
    Karolinska University Hospital at Huddinge, Stockholm, Sweden.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Nowak, J.
    Karolinska University Hospital at Huddinge, Stockholm, Sweden.
    Ramesh, S. S.
    Bhagwan Mahavir Jain Heart Center, Bangalore, India.
    Saha, S. K.
    Karolinska University Hospital at Huddinge, Stockholm, Sweden.
    Differing myocardial response to a single session of hemodialysis in end-stage renal disease with and without type 2 diabetes mellitus and coronary artery disease2006In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 4, no 9Article in journal (Refereed)
    Abstract [en]

    Background: Though hemodialysis (HD) acutely improves cardiac function, the impact of background diseases like coronary artery disease (CAD) and Type 2 diabetes (DM) in the setting of end-stage renal disease (ESRD) is not known. Tissue velocity echocardiography (TVE) offers a fast choice to follow changes in myocardial function after HD in ESRD with concomitant DM and/or CAD. Methods: 46 subjects (17 with ESRD, Group 1; 15 with DM, Group 2; 14 with DM+CAD, Group 3) underwent standard and TVE prior to and shortly after HD. Besides standard Doppler variables, regional myocardial systolic and diastolic velocities, as well as systolic strain rate were post processed. Results: Compared with pre-HD, post-HD body weight (kg) significantly decreased in all the three groups (51 ± 9 vs. 48 ± 8, 62 ± 10 vs.59 ± 10, and 61 ± 9 vs. 58 ± 9 respectively; all p < 0.01). Left ventricular end diastolic dimensions (mm) also decreased post- HD (46 ± 5 vs. 42 ± 7, 53 ± 7 vs. 50 ± 7, 51 ± 7 vs. 47 ± 8 respectively; all p < 0.01). Regional longitudinal peak systolic velocity in septum (cm/s) significantly increased post-HD in Group 1(5.7 ± 1.6 vs. 7.2 ± 2.3; p < 0.001) while remained unchanged in the other two groups. Similar trends were noted in other left ventricular walls. When the myocardial velocities (cm/s) were computed globally, the improvement was seen only in Group 1 (6.3 ± 1.5 vs. 7.9 ± 2.0; p < 0.001). Global early regional diastolic velocity (cm/s) improved in Group 1, remained unchanged in Group 2, while significantly decreased in Group 3(-5.9 ± 1.3 vs. -4.1 ± 1.8; p < 0.01). Global systolic strain rate (1/sec) increased in the first 2 Groups but remained unchanged (-0.87 ± 0.4 vs. -0.94 ± 0.3; p = ns) in Group 3. Conclusion: A single HD session improves LV function only in ESRD without coexistent DM and/or CAD. The present data suggest that not only dialysis-dependent changes in loading conditions but also co-existent background diseases determine the myocardial response to HD.

  • 15.
    Granstam, Sven-Olof
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
    Björklund, Erik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology.
    Wikström, Gerhard
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology.
    Roos, Magnus W
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
    Use of echocardiographic pulmonary acceleration time and estimated vascular resistance for the evaluation of possible pulmonary hypertension2013In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 11, p. 7-Article in journal (Refereed)
    Abstract [en]

    BACKGROUND:

    During ultrasound examination, tricuspid regurgitation may be absent or gives a signal that is not reliable for the estimation of systolic pulmonary pressure. The aim of this study was to evaluate the usefulness of acceleration time (AT) from the right ventricular outflow tract (RVOT) as an estimation of the trans-tricuspid valve gradient (TTVG) and to investigate the correlation between estimated and invasive pulmonary vascular resistance (PVR).

    METHODS:

    The AT was correlated to the TTVG measured with routine standard echocardiography in 121 patients. In a subgroup of 29 patients, systolic pulmonary pressure (SPAP) and mean pulmonary arterial pressure (MPAP) were obtained from recent right heart catheterization (RHC).

    RESULTS:

    We found no significant correlation between the estimation of right atrial pressure (RAP) by echocardiography and the RAP obtained by RHC. Estimated SPAP (TTGV + RAP mean from RHC) showed a good linear relation to invasively measured SPAP. TTVG and AT showed a non-linear relation, similar to SPAP and MPAP measured by catheterization and AT. For detection of SPAP above 38 mmHg a cut-off for AT of 100 ms resulted in a sensitivity of 89% and a specificity of 84%. For detection of MPAP above 25 mmHg a cut-off for AT of 100 ms resulted in similar sensitivity and specificity. Invasive PVR and the ratio of TTVG and the time velocity integral of the RVOT (TVI RVOT ) had a strong linear relation.

    CONCLUSIONS:

    Our study confirms that AT appears to be useful for the evaluation of pulmonary hypertension. In high risk patients, an AT of less than 100 ms indicates a high probability of pulmonary hypertension. Furthermore, PVR estimation by ultrasound seems preferably be done by using the ratio of TTVG and TVI RVOT.

  • 16.
    Gudmundsson, Petri
    et al.
    Malmö högskola, Faculty of Health and Society (HS).
    Shahgaldi, Kambiz
    Winter, Reidar
    Dencker, Magnus
    Kitlinski, Mariusz
    Thorsson, Ola
    Ljunggren, Lennart
    Malmö högskola, Faculty of Health and Society (HS).
    Willenheimer, Ronnie
    Head to head comparisons of two modalities of perfusion adenosine stress echocardiography with simultaneous SPECT2009In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 7, no 19, article id 19Article in journal (Refereed)
    Abstract [en]

    Background: Real-time perfusion (RTP) contrast echocardiography can be used during adenosine stress echocardiography (ASE) to evaluate myocardial ischemia. We compared two different types of RTP power modulation techniques, angiomode (AM) and high-resolution grayscale (HR), with 99mTc-tetrofosmin single-photon emission computed tomography (SPECT) for the detection of myocardial ischemia. Methods: Patients with known or suspected coronary artery disease (CAD), admitted to SPECT, were prospectively invited to participate. Patients underwent RTP imaging (SONOS 5500) using AM and HR during Sonovue® infusion, before and throughout the adenosine stress, also used for SPECT. Analysis of myocardial perfusion and wall motion by RTP-ASE were done for AM and HR at different time points, blinded to one another and to SPECT. Each segment was attributed to one of the three main coronary vessel areas of interest. Results: In 50 patients, 150 coronary areas were analyzed by SPECT and RTP-ASE AM and HR. SPECT showed evidence of ischemia in 13 out of 50 patients. There was no significant difference between AM and HR in detecting ischemia (p = 0.08). The agreement for AM and HR, compared to SPECT, was 93% and 96%, with Kappa values of 0.67 and 0.75, respectively (p < 0.001). Conclusion: There was no significant difference between AM and HR in correctly detecting myocardial ischemia as judged by SPECT. This suggests that different types of RTP modalities give comparable data during RTP-ASE in patients with known or suspected CAD.

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  • 17.
    Gudmundsson, Petri
    et al.
    Malmö högskola, Faculty of Health and Society (HS).
    Shahgaldi, Kambiz
    Winter, Reidar
    Dencker, Magnus
    Kitlinski, Mariusz
    Thorsson, Ola
    Willenheimer, Ronnie
    Ljunggren, Lennart
    Malmö högskola, Faculty of Health and Society (HS).
    Quantitative detection of myocardial ischaemia by stress echocardiography; a comparison with SPECT2009In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 7, no 28, article id 28Article in journal (Refereed)
    Abstract [en]

    Aims: Real-time perfusion (RTP) adenosine stress echocardiography (ASE) can be used to visually evaluate myocardial ischaemia. The RTP power modulation technique angio-mode (AM), provides images for off-line perfusion quantification using Qontrast® software, generating values of peak signal intensity (A), myocardial blood flow velocity (β) and myocardial blood flow (Axβ). By comparing rest and stress values, their respective reserve values (A-r, β-r, Axβ-r) are generated. We evaluated myocardial ischaemia by RTP-ASE Qontrast® quantification, compared to visual perfusion evaluation with 99mTc-tetrofosmin singlephoton emission computed tomography (SPECT). Methods and Results: Patients admitted to SPECT underwent RTP-ASE (SONOS 5500) using AM during Sonovue® infusion, before and throughout adenosine stress, also used for SPECT. Visual myocardial perfusion and wall motion analysis, and Qontrast® quantification, were blindly compared to one another and to SPECT, at different time points off-line. We analyzed 201 coronary territories (left anterior descendent [LAD], left circumflex [LCx] and right coronary [RCA] artery territories) in 67 patients. SPECT showed ischaemia in 18 patients and 19 territories. Receiver operator characteristics and kappa values showed significant agreement with SPECT only for β-r and Axβ-r in all segments: area under the curve 0.678 and 0.665; P < 0.001 and < 0.01, respectively. The closest agreements were seen in the LAD territory: kappa 0.442 for both β-r and Axβ- r; P < 0.01. Visual evaluation of ischaemia showed good agreement with SPECT: accuracy 93%; kappa 0.67; P < 0.001; without non-interpretable territories. Conclusion: In this agreement study with SPECT, RTP-ASE Qontrast® quantification of myocardial ischaemia was less accurate and less feasible than visual evaluation and needs further development to be clinically useful.

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  • 18.
    Herling, Lotta
    et al.
    Karolinska Inst, Dept Clin Sci Intervent & Technol, CLINTEC, Stockholm, Sweden.;Karolinska Univ Hosp, Ctr Fetal Med, Dept Obstet & Gynecol, Stockholm, Sweden..
    Johnson, Jonas
    Karolinska Univ Hosp, Ctr Fetal Med, Dept Obstet & Gynecol, Stockholm, Sweden..
    Ferm-Widlund, Kjerstin
    Karolinska Univ Hosp, Ctr Fetal Med, Dept Obstet & Gynecol, Stockholm, Sweden..
    Bergholm, Fredrik
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Lindgren, Peter
    Karolinska Inst, Dept Clin Sci Intervent & Technol, CLINTEC, Stockholm, Sweden.;Karolinska Univ Hosp, Ctr Fetal Med, Dept Obstet & Gynecol, Stockholm, Sweden..
    Sonesson, Sven-Erik
    Karolinska Univ Hosp, Dept Womens & Childrens Hlth, Pediat Cardiol Unit, Stockholm, Sweden..
    Acharya, Ganesh
    Karolinska Inst, Dept Clin Sci Intervent & Technol, CLINTEC, Stockholm, Sweden.;Karolinska Univ Hosp, Ctr Fetal Med, Dept Obstet & Gynecol, Stockholm, Sweden.;UiT Arctic Univ Norway, Dept Clin Med, Womens Hlth & Perinatol Res Grp, Tromso, Norway..
    Westgren, Magnus
    Karolinska Inst, Dept Clin Sci Intervent & Technol, CLINTEC, Stockholm, Sweden.;Karolinska Univ Hosp, Ctr Fetal Med, Dept Obstet & Gynecol, Stockholm, Sweden..
    Fetal cardiac function at intrauterine transfusion assessed by automated analysis of color tissue Doppler recordings2020In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 18, no 1, article id 34Article in journal (Refereed)
    Abstract [en]

    Background Fetal anemia is associated with a hyperdynamic circulation and cardiac remodeling. Rapid intrauterine transfusion (IUT) of blood with high hematocrit and viscosity into the umbilical vein used to treat this condition can temporarily further affect fetal heart function. The aim of this study was to evaluate the short-term changes in fetal myocardial function caused by IUT using automated analysis of cine-loops of the fetal heart obtained by color tissue Doppler imaging (cTDI). Methods Fetal echocardiography was performed before and after IUT. cTDI recordings were obtained in a four-chamber view and regions of interest were placed at the atrioventricular plane in the left ventricular (LV), right ventricular (RV) and septal walls. Myocardial velocities were analyzed by an automated analysis software to obtain peak myocardial velocities during atrial contraction (Am), ventricular ejection (Sm), rapid ventricular filling (Em) and Em/Am ratio was calculated. Myocardial velocities were converted to z-scores using published reference ranges. Delta z-scores (after minus before IUT) were calculated. Correlations were assessed between variables and hemoglobin before IUT. Results Thirty-two fetuses underwent 70 IUTs. Fourteen were first time transfusions. In the LV and septal walls, all myocardial velocities were significantly increased compared to normal values, whereas in the RV only Sm was increased before IUT (z-scores 0.26-0.52). In first time IUTs, there was a negative correlation between LV Em (rho = - 0.61,p = 0.036) and LV Em/Am (rho = - 0.82,p = 0.001) z-scores and hemoglobin before IUT. The peak myocardial velocities that were increased before IUT decreased, whereas LV Em/Am increased significantly after IUT. Conclusions This study showed that peak myocardial velocities assessed by cTDI are increased in fetuses before IUT reflecting the physiology of hyperdynamic circulation. In these fetuses, the fetal heart is able to adapt and efficiently handle the volume load caused by IUT by altering its myocardial function.

  • 19. Herling, Lotta
    et al.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering.
    Ferm-Widlund, Kjerstin
    Lindgren, Peter
    Acharya, Ganesh
    Westgren, Magnus
    Automated analysis of color tissue Doppler velocity recordings of the fetal myocardium using a new algorithm2015In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 13, article id 39Article in journal (Refereed)
    Abstract [en]

    Background: Tissue Doppler imaging (TDI) can be used to assess fetal cardiac function and it has been shown to detect changes associated with hypoxia in animal models. However, the analysis is cumbersome and time consuming. The main objective of this study was to evaluate the feasibility of a new algorithm developed for the automated analysis of color TDI velocity recordings of the fetal myocardium. Furthermore, we wanted to assess the effect of different sizes of region of interests (ROI) on the measurement of cardiac cycle time intervals and myocardial velocities at different gestations. Methods: This study included analysis of 261 TDI velocity traces obtained from 17 fetal echocardiographic examinations performed longitudinally on five pregnant women. Cine-loops of fetal cardiac four chamber view were recorded with color overlay in TDI mode and stored for off-line analysis. ROIs of different sizes were placed at the level of the atrioventricular plane in the septum and in the right and left ventricular walls of the fetal heart. An automated algorithm was then used for the analysis of velocity traces. Results: Out of the total 261 velocity traces, it was possible to analyze 203 (78 %) traces with the automated algorithm. It was possible to analyze 93 % (81/87) of traces recorded from the right ventricular wall, 82 % (71/87) from the left ventricular wall and 59 % (51/87) from the septum. There was a trend towards decreasing myocardial velocities with increasing ROI length. However, the cardiac cycle time intervals were similar irrespective of which ROI size was used. Conclusions: An automated analysis of color TDI fetal myocardial velocity traces seems feasible, especially for measuring cardiac cycle time intervals, and has the potential for clinical application.

  • 20.
    Janjic, J.
    et al.
    Biosense Webster, Johnson and Johnson Medical, Via del Mare 56, Rome, Pomezia, 00071, Italy.
    Larsson, M. K.
    Karolinska University Hospital, Eugeniavägen 3, Stockholm, SE-171 76, Sweden.
    Bjällmark, Anna
    Jönköping University, School of Health and Welfare, HHJ, Dep. of Natural Science and Biomedicine. Jönköping University, School of Health and Welfare, HHJ. Biomedical Platform.
    In-vitro sonothrombolysis using thick-shelled polymer microbubbles-a comparison with thin-shelled microbubbles2020In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 18, no 1, article id 12Article in journal (Refereed)
    Abstract [en]

    Background: Vascular thrombosis can be treated pharmacologically, however, serious shortcomings such as bleeding may occur. Several studies suggest that sonothrombolysis can induce lysis of the clots using ultrasound. Moreover, intravenously injected thin-shelled microbubbles (MBs) combined with ultrasound can further improve clot lysis. Thick-shelled MBs have been used for drug delivery, targeting and multimodal imaging. However, their capability to enhance sonothrombolysis is unknown. In this study, using an in-vitro set-up, the enhancement of clot lysis using ultrasound and thick-shelled MBs was investigated. Thin-shelled MBs was used for comparison. Method: The main components in the in-vitro set-up was a vessel mimicking phantom, a pressure mearing system and programmable ultrasound machine. Blood clots were injected and entrapped on a pore mesh in the vessel phantom. Four different protocols for ultrasound transmission and MB exposure (7 blood clots/protocol) were considered together with a control test were no MBs and ultrasound were used. For each protocol, ultrasound exposure of 20 min was used. The upstream pressure of the partially occluded mesh was continuously measured to assess clot burden. At the end of each protocol blood clots were removed from the phantom and the clot mass loss was computed. Results: For the thick-shelled MBs no difference in clot mass loss compared with the control tests was found. A 10% increase in the clot mass loss compared with the control tests was found when using thin-shelled MBs and low pressure/long pulses ultrasound exposure. Similarly, in terms of upstream pressure over exposure time, no differences were found when using the thick-shelled MBs, whereas thin-shelled MBs showed a 15% decrease achieved within the first 4 min of ultrasound exposure. Conclusion: No increase in clot lysis was achieved using thick-shelled MBs as demonstrated by no significant change in clot mass or upstream pressure. Although thick-shelled MBs are promising for targeting and drug delivery, they do not enhance clot lysis when considering the ultrasound sequences used in this study. On the other hand, ultrasound in combination with thin-shelled MBs can facilitate thrombolysis when applying long ultrasound pulses with low pressure.

  • 21.
    Jashari, Haki
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Rydberg, Annika
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Ibrahimi, Pranvera
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Bajraktari, Gani
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Kryeziu, Lindita
    Jashari, Fisnik
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Henein, Michael Y.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Normal ranges of left ventricular strain in children: a meta-analysis2015In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 13, article id 37Article, review/survey (Refereed)
    Abstract [en]

    Aims: The definition of normal values of two-dimensional speckle-tracking echocardiography derived left ventricular (LV) deformation parameters, is of critical importance for the routine application of this modality in children. The objectives of this study were to perform a meta-analysis of normal ranges for longitudinal, circumferential and radial strain/strain rate values and to identify confounders that may contribute to differences in reported measures. Methods and Results: A systematic search was conducted. Studies describing normal healthy subjects and observational studies that used control groups as a comparison were included. Data were combined using a random-effect model. Effects of demographic, clinical and equipment variables were assessed through meta-regression. The search identified 1,192 subjects form 28 articles. Longitudinal strain (LS) normal mean values varied from -12.9 to -26.5 (mean, -20.5; 95 % CI, -20.0 to -21.0). Normal mean values of circumferential strain (CS) varied from -10.5 to -27.0 (mean, -22.06; 95 % CI, -21.5 to -22.5). Radial strain (RS) normal mean values varied from 24.9 to 62.1 (mean, 45.4; 95 % CI, 43.0 to 47.8). Meta-regression showed LV end diastolic diameter as a significant determinant of variation for LS. Longitudinal systolic strain rate (LSRs) was significantly determined by the age and RS by the type of vendor used. Conclusion: Variations among different normal ranges were dependent on the vendor used, LV end-diastolic diameter and age. Vendor-independent software for analyzing myocardial deformation in children, using images from different vendors would be the ideal solution for strain measurements or else using the same system for patient's follow up.

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  • 22.
    Jorgensen, Peter Godsk
    et al.
    Gentofte Hosp, Dept Cardiol, Univ Copenhagen, Copenhagen, Denmark.
    Arnemo, Jon
    Fac Appl Ecol & Agr Sci, Dept Forestry & Wildlife Management, Hedmark Coll, Elverum, Norway; Fac Forest Sci, Dept Wildlife Fish & Environm Studies, Swedish Univ Agr Sci, Umeå, Sweden.
    Swenson, Jon E.
    Dept Ecol & Nat Resource Management, Norwegian Univ Life Sci, Ås, Norway; Norwegian Inst Nat Res, Trondheim, Norway.
    Jensen, Jan S.
    Dept Cardiol, Gentofte Hosp, Univ Copenhagen, Copenhagen, Denmark.
    Galatius, Soren
    Dept Cardiol, Gentofte Hosp, Univ Copenhagen, Copenhagen, Denmark.
    Fröbert, Ole
    Örebro University Hospital. Department of Cardiology, Örebro University Hospital, Örebro, Sweden.
    Low cardiac output as physiological phenomenon in hibernating, free-ranging Scandinavian brown bears (Ursus arctos) - an observational study2014In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 12, article id 36Article in journal (Refereed)
    Abstract [en]

    Background: Despite 5-7 months of physical inactivity during hibernation, brown bears (Ursus arctos) are able to cope with physiological conditions that would be detrimental to humans. During hibernation, the tissue metabolic demands fall to 25% of the active state. Our objective was to assess cardiac function associated with metabolic depression in the hibernating vs. active states in free-ranging Scandinavian brown bears.

    Methods: We performed echocardiography on seven free-ranging brown bears in Dalarna, Sweden, anesthetized with medetomidine-zolazepam-tiletamine-ketamine during winter hibernation in February 2013 and with medetomidine-zolazepam-tiletamine during active state in June 2013. We measured cardiac output noninvasively using estimates of hemodynamics obtained by pulsed wave Doppler echocardiography and 2D imaging. Comparisons were made using paired T-tests.

    Results: During hibernation, all hemodynamic indices were significantly decreased (hibernating vs. active state): mean heart rate was 26.0 (standard deviation (SD): 5.6) beats per min vs. 75.0 (SD: 17.1) per min (P = 0.002), mean stroke volume 32.3 (SD: 5.2) ml vs. 47.1 (SD: 7.9) ml (P = 0.008), mean cardiac output 0.86 (SD: 0.31) l/min vs. 3.54 (SD: 1.04) l/min (P = 0.003), and mean cardiac index 0.63 (SD: 0.21) l/min/kg vs. 2.45 (SD: 0.52) l/min/ m(2) (P < 0.001). Spontaneous echo contrast was present in all cardiac chambers in all seven bears during hibernation, despite the absence of atrial arrhythmias and valvular disease.

    Conclusion: Free-ranging brown bears demonstrate hemodynamics comparable to humans during active state, whereas during hibernation, we documented extremely low-flow hemodynamics. Understanding these physiological changes in bears may help to gain insight into the mechanisms of cardiogenic shock and heart failure in humans.

  • 23.
    Jorstig, Stina
    et al.
    Örebro University, School of Medical Sciences. Örebro University Hospital. Faculty of Medicine and Health, Örebro University Biomedical Engineering, Örebro University Hospital, Örebro, Sweden.
    Waldenborg, Micael
    Örebro University Hospital. Örebro University, School of Medical Sciences. Faculty of Medicine and Health and Department of Clinical Physiology, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Lidén, Mats
    Örebro University, School of Medical Sciences. Örebro University Hospital. Faculty of Medicine and Health and Department of Radiology, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Thunberg, Per
    Örebro University, School of Medical Sciences. Örebro University Hospital. Faculty of Medicine and Health and Department of Medical Physics, Department of Medical Physics, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Right ventricular ejection fraction measurements using two-dimensional transthoracic echocardiography by applying an ellipsoid model2017In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 15, article id 4Article in journal (Refereed)
    Abstract [en]

    Background: There is today no established approach to estimate right ventricular ejection fraction (RVEF) using 2D transthoracic echocardiography (TTE). The aim of this study was to evaluate a new method for RVEF calculations using 2D TTE and compare the results with cardiac magnetic resonance (CMR) imaging and tricuspid annular plane systolic excursion (TAPSE).

    Methods: A total of 37 subjects, 25 retrospectively included patients and twelve healthy volunteers, were included to give a wide range of RVEF. The right ventricle (RV) was modeled as a part of an ellipsoid enabling calculation of the RV volume by combining three distance measurements. RVEF calculated according to the model, RVEFTTE, were compared with reference CMR-derived RVEF, RVEFCMR. Further, TAPSE was measured in the TTE images and the correlations were calculated between RVEFTTE, TAPSE and RVEFCMR.

    Results: The mean values were RVEFCMR = 43 +/- 12% (range 20-66%) and RVEFTTE = 50 +/- 9% (range 34-65%). There was a high correlation (r = 0.80, p < 0.001) between RVEFTTE and RVEFCMR. Bland-Altman analysis showed a mean difference between RVEFCMR and RVEFTTE of 6 percentage points (ppt) with limits of agreement from -11 to 23 ppt. The mean value for TAPSE was 19 +/- 5 mm and the correlation between TAPSE and RVEFCMR was moderate (r = 0.54, p < 0.001). The correlation between RVEFTTE and RVEFCMR was significantly higher (p < 0.05) than the correlation between TAPSE and RVEFCMR.

    Conclusions: The ellipsoid model shows promise for RVEF calculations using 2D TTE for a wide range of RVEF, providing RVEF estimates that were significantly better correlated to RVEF obtained from CMR compared to TAPSE.

  • 24.
    Larsson, Malin K.
    et al.
    KTH, Medicinsk teknik.
    Da Silva, Cristina
    Gunyeli, Elif
    Bin Ilami, Ali Akebat
    Szummer, Karolina
    Winter, Reidar
    KTH, Medicinsk teknik.
    Bjällmark, Anna
    KTH, Medicinsk teknik.
    The potential clinical value of contrast-enhanced echocardiography beyond current recommendations2016In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 14, article id 2Article in journal (Refereed)
    Abstract [en]

    Background: Contrast agents are used in resting echocardiography to opacify the left ventricular (LV) cavity and to improve LV endocardial border delineation in patients with suboptimal image quality. If a wider use of contrast-enhanced echocardiography would be adopted instead of the current selective approach, diagnoses such as myocardial ischemia and LV structural abnormalities could potentially be detected earlier. The aim was therefore to retrospectively investigate if contrast- enhanced echocardiography beyond the current recommendations for contrast agent usage affects assessment of wall motion abnormalities, ejection fraction (EF) and detection of LV structural abnormalities. A secondary aim was to evaluate the user dependency during image analysis. Methods: Experienced readers (n = 4) evaluated wall motion score index (WMSI) and measured EF on greyscale and contrast-enhanced images from 192 patients without indications for contrast-enhanced echocardiography. Additionally, screening for LV structural abnormalities was performed. Repeated measurements were performed in 20 patients by the experienced as well as by inexperienced (n = 2) readers. Results: Contrast analysis resulted in significantly higher WMSI compared to greyscale analysis (p < 0.003). Of the 83 patients, classified as healthy by greyscale analysis, 55 % were re-classified with motion abnormalities by contrast analysis. No significant difference in EF classification (>= 55 %, 45-54 %, 30-44 %, < 30 %) was observed. LV structural abnormalities, such as increased trabeculation (n = 21), apical aneurysm (n = 4), hypertrophy (n = 1) and thrombus (n = 1) were detected during contrast analysis. Intra- and interobserver variability for experienced readers as well as the variability between inexperienced and experienced readers decreased for WMSI and EF after contrast analysis. Conclusions: Contrast-enhanced echocardiography beyond current recommendations for contrast agent usage increased the number of detected wall motion and LV structural abnormalities. Moreover, contrast- enhanced echocardiography increased reproducibility for assessment of WMSI and EF.

  • 25.
    Larsson, Malin K.
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Da Silva, Cristina
    Gunyeli, Elif
    Bin Ilami, Ali Akebat
    Szummer, Karolina
    Winter, Reidar
    KTH, School of Technology and Health (STH), Medical Engineering. Karolinska University Hospital, Sweden.
    Bjällmark, Anna
    KTH, School of Technology and Health (STH), Medical Engineering. Karolinska Institutet, Sweden.
    The potential clinical value of contrast-enhanced echocardiography beyond current recommendations2016In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 14, article id 2Article in journal (Refereed)
    Abstract [en]

    Background: Contrast agents are used in resting echocardiography to opacify the left ventricular (LV) cavity and to improve LV endocardial border delineation in patients with suboptimal image quality. If a wider use of contrast-enhanced echocardiography would be adopted instead of the current selective approach, diagnoses such as myocardial ischemia and LV structural abnormalities could potentially be detected earlier. The aim was therefore to retrospectively investigate if contrast- enhanced echocardiography beyond the current recommendations for contrast agent usage affects assessment of wall motion abnormalities, ejection fraction (EF) and detection of LV structural abnormalities. A secondary aim was to evaluate the user dependency during image analysis. Methods: Experienced readers (n = 4) evaluated wall motion score index (WMSI) and measured EF on greyscale and contrast-enhanced images from 192 patients without indications for contrast-enhanced echocardiography. Additionally, screening for LV structural abnormalities was performed. Repeated measurements were performed in 20 patients by the experienced as well as by inexperienced (n = 2) readers. Results: Contrast analysis resulted in significantly higher WMSI compared to greyscale analysis (p < 0.003). Of the 83 patients, classified as healthy by greyscale analysis, 55 % were re-classified with motion abnormalities by contrast analysis. No significant difference in EF classification (>= 55 %, 45-54 %, 30-44 %, < 30 %) was observed. LV structural abnormalities, such as increased trabeculation (n = 21), apical aneurysm (n = 4), hypertrophy (n = 1) and thrombus (n = 1) were detected during contrast analysis. Intra- and interobserver variability for experienced readers as well as the variability between inexperienced and experienced readers decreased for WMSI and EF after contrast analysis. Conclusions: Contrast-enhanced echocardiography beyond current recommendations for contrast agent usage increased the number of detected wall motion and LV structural abnormalities. Moreover, contrast- enhanced echocardiography increased reproducibility for assessment of WMSI and EF.

  • 26.
    Larsson, Malin K.
    et al.
    KTH, Medicinsk bildteknik.
    Larsson, Matilda
    KTH, Medicinsk bildteknik.
    Nowak, Greg
    Paradossi, Gaio
    Brodin, Lars-Åke
    KTH, Medicinsk bildteknik.
    Janerot Sjöberg, Birgitta
    KTH, Medicinsk teknik.
    Caidahl, Kenneth
    Bjällmark, Anna
    KTH, Medicinsk bildteknik.
    Endocardial border delineation capability of a novel multimodal polymer-shelled contrast agent2014In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 12, p. 24-Article in journal (Refereed)
    Abstract [en]

    Background: A novel polymer-shelled contrast agent (CA) with multimodal and target-specific potential was developed recently. To determine its ultrasonic diagnostic features, we evaluated the endocardial border delineation as visualized in a porcine model and the concomitant effect on physiological variables. Methods: Three doses of the novel polymer-shelled CA (1.5 ml, 3 ml, and 5 ml [5 x 10(8) microbubbles (MBs)/ml]) and the commercially available CA SonoVue (1.5 ml [2-5 x 10(8) MBs/ml]) were used. Visual evaluations of ultrasound images of the left ventricle were independently performed by three observers who graded each segment in a 6-segment model as either 0 = not visible, 1 = weakly visible, or 2 = visible. Moreover, the duration of clinically useful contrast enhancement and the left ventricular opacification were determined. During anesthesia, oxygen saturation, heart rate, and arterial pressure were sampled every minute and the effect of injection of CA on these physiological variables was evaluated. Results: The highest dose of the polymer-shelled CA gave results comparable to SonoVue. Thus, no significant difference in the overall segment score distribution (2-47-95 vs. 1-39-104), time for clinically sufficient contrast enhancement (20-40 s for both) and left ventricular overall opacification was found. In contrast, when comparing the endocardial border delineation capacity for different regions SonoVue showed significantly higher segment scores for base and mid, except for the mid region when injecting 1.5 ml of the polymer-shelled CA. Neither high nor low doses of the polymer-shelled CA significantly affected the investigated physiological variables. Conclusions: This study demonstrated that the novel polymer-shelled CA can be used in contrast-enhanced diagnostic imaging without influence on major physiological variables.

  • 27.
    Larsson, Malin K.
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Nowak, Greg
    Paradossi, Gaio
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Janerot Sjöberg, Birgitta
    KTH, School of Technology and Health (STH), Medical Engineering.
    Caidahl, Kenneth
    Bjällmark, Anna
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Endocardial border delineation capability of a novel multimodal polymer-shelled contrast agent2014In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 12, p. 24-Article in journal (Refereed)
    Abstract [en]

    Background: A novel polymer-shelled contrast agent (CA) with multimodal and target-specific potential was developed recently. To determine its ultrasonic diagnostic features, we evaluated the endocardial border delineation as visualized in a porcine model and the concomitant effect on physiological variables. Methods: Three doses of the novel polymer-shelled CA (1.5 ml, 3 ml, and 5 ml [5 x 10(8) microbubbles (MBs)/ml]) and the commercially available CA SonoVue (1.5 ml [2-5 x 10(8) MBs/ml]) were used. Visual evaluations of ultrasound images of the left ventricle were independently performed by three observers who graded each segment in a 6-segment model as either 0 = not visible, 1 = weakly visible, or 2 = visible. Moreover, the duration of clinically useful contrast enhancement and the left ventricular opacification were determined. During anesthesia, oxygen saturation, heart rate, and arterial pressure were sampled every minute and the effect of injection of CA on these physiological variables was evaluated. Results: The highest dose of the polymer-shelled CA gave results comparable to SonoVue. Thus, no significant difference in the overall segment score distribution (2-47-95 vs. 1-39-104), time for clinically sufficient contrast enhancement (20-40 s for both) and left ventricular overall opacification was found. In contrast, when comparing the endocardial border delineation capacity for different regions SonoVue showed significantly higher segment scores for base and mid, except for the mid region when injecting 1.5 ml of the polymer-shelled CA. Neither high nor low doses of the polymer-shelled CA significantly affected the investigated physiological variables. Conclusions: This study demonstrated that the novel polymer-shelled CA can be used in contrast-enhanced diagnostic imaging without influence on major physiological variables.

  • 28.
    Larsson, Malin
    et al.
    KTH, Medicinsk teknik.
    Larsson, Matilda
    KTH, Medicinsk teknik.
    Oddo, Letizia
    Margheritelli, Silvia
    Paradossi, Gaio
    Nowak, Jacek
    Brodin, Lars-Åke
    KTH, Medicinsk teknik.
    Caidahl, Kenneth
    Bjällmark, Anna
    KTH, Medicinsk teknik.
    Visualization of multimodal polymer-shelled contrast agents using ultrasound contrast sequences: An experimental study in a tissue mimicking flow phantom2013In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 11, p. 33-Article in journal (Refereed)
    Abstract [en]

    Background: A multimodal polymer-shelled contrast agent (CA) with target specific potential was recently developed and tested for its acoustic properties in a single element transducer setup. Since the developed polymeric CA has different chemical composition than the commercially available CAs, there is an interest to study its acoustic response when using clinical ultrasound systems. The aim of this study was therefore to investigate the acoustic response by studying the visualization capability and shadowing effect of three polymer-shelled CAs when using optimized sequences for contrast imaging. Methods: The acoustic response of three types of the multimodal CA was evaluated in a tissue mimicking flow phantom setup by measuring contrast to tissue ratio (CTR) and acoustic shadowing using five image sequences optimized for contrast imaging. The measurements were performed over a mechanical index (MI) range of 0.2-1.2 at three CA concentrations (10(6), 10(5), 10(4) microbubbles/ml). Results: The CTR-values were found to vary with the applied contrast sequence, MI and CA. The highest CTR-values were obtained when a contrast sequence optimized for higher MI imaging was used. At a CA concentration of 106 microbubbles/ml, acoustic shadowing was observed for all contrast sequences and CAs. Conclusions: The CAs showed the potential to enhance ultrasound images generated by available contrast sequences. A CA concentration of 106 MBs/ml implies a non-linear relation between MB concentration and image intensity.

  • 29.
    Larsson, Malin
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering.
    Oddo, Letizia
    Margheritelli, Silvia
    Paradossi, Gaio
    Nowak, Jacek
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Caidahl, Kenneth
    Bjällmark, Anna
    KTH, School of Technology and Health (STH), Medical Engineering.
    Visualization of multimodal polymer-shelled contrast agents using ultrasound contrast sequences: an experimental study in a tissue mimicking flow phantom2013In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 11, p. 33-Article in journal (Refereed)
    Abstract [en]

    Background: A multimodal polymer-shelled contrast agent (CA) with target specific potential was recently developed and tested for its acoustic properties in a single element transducer setup. Since the developed polymeric CA has different chemical composition than the commercially available CAs, there is an interest to study its acoustic response when using clinical ultrasound systems. The aim of this study was therefore to investigate the acoustic response by studying the visualization capability and shadowing effect of three polymer-shelled CAs when using optimized sequences for contrast imaging. Methods: The acoustic response of three types of the multimodal CA was evaluated in a tissue mimicking flow phantom setup by measuring contrast to tissue ratio (CTR) and acoustic shadowing using five image sequences optimized for contrast imaging. The measurements were performed over a mechanical index (MI) range of 0.2-1.2 at three CA concentrations (10(6), 10(5), 10(4) microbubbles/ml). Results: The CTR-values were found to vary with the applied contrast sequence, MI and CA. The highest CTR-values were obtained when a contrast sequence optimized for higher MI imaging was used. At a CA concentration of 106 microbubbles/ml, acoustic shadowing was observed for all contrast sequences and CAs. Conclusions: The CAs showed the potential to enhance ultrasound images generated by available contrast sequences. A CA concentration of 106 MBs/ml implies a non-linear relation between MB concentration and image intensity.

  • 30.
    Larsson, Matilda
    et al.
    School for Technology and Health, Royal Institute of Technology, Sweden.
    Bjällmark, Anna
    School for Technology and Health, Royal Institute of Technology, Sweden.
    Johnson, Jens
    School for Technology and Health, Royal Institute of Technology, Sweden.
    Winter, Reidar
    Department of Clinical Physiology, Karolinska University Hospital, Sweden.
    Brodin, Lars-Åke
    School for Technology and Health, Royal Institute of Technology, Sweden.
    Lundbäck, Stig
    Gripping Heart AB, KTH Business Lab, Sweden.
    State diagrams of the heart – a new approach to describing cardiac mechanics2009In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 7, no 22Article in journal (Refereed)
    Abstract [en]

    Background: Cardiac time intervals have been described as a measure of cardiac performance, where prolongation, shortening and delay of the different time intervals have been evaluated as markers of cardiac dysfunction. A relatively recently developed method with improved ability to measure cardiac events is Tissue Doppler Imaging (TDI), allowing accurate measurement of myocardial movements.

    Methods: We propose the state diagram of the heart as a new visualization tool for cardiac time intervals, presenting comparative, normalized data of systolic and diastolic performance, providing a more complete overview of cardiac function. This study aimed to test the feasibility of the state diagram method by presenting examples demonstrating its potential use in the clinical setting and by performing a clinical study, which included a comparison of the state diagram method with established echocardiography methods (E/E' ratio, LVEF and WMSI). The population in the clinical study consisted of seven patients with non ST-elevation myocardial infarction (NSTEMI) and seven control subjects, individually matched according to age and gender. The state diagram of the heart was generated from TDI curves from seven positions in the myocardium, visualizing the inter- and intraventricular function of the heart by displaying the cardiac phases.

    Results: The clinical examples demonstrated that the state diagram allows for an intuitive visualization of pathological patterns as ischemia and dyssynchrony. Further, significant differences in percentage duration between the control group and the NSTEMI group were found in eight of the totally twenty phases (10 phases for each ventricle), e.g. in the transition phases (Pre-Ejection and Post-Ejection). These phases were significantly longer (> 2.18%) for the NSTEMI group than for the control group (p < 0.05). No significant differences between the groups were found for the established echocardiography methods.

    Conclusion: The test results clearly indicate that the state diagram has potential to be an efficient tool for visualization of cardiac dysfunction and for detection of NSTEMI.

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  • 31.
    Larsson, Matilda
    et al.
    KTH, School of Technology and Health (STH).
    Bjällmark, Anna
    KTH, School of Technology and Health (STH).
    Johnson, Jonas
    KTH, School of Technology and Health (STH).
    Winter, Reidar
    Karolinska Univ Hosp, Dept Clin Physiol, SE-14186 Stockholm, Sweden..
    Brodin, Lars-Ake
    KTH, School of Technology and Health (STH).
    Lundbäck, Stig
    KTH.
    State diagrams of the heart - a new approach to describing cardiac mechanics2009In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 7, article id 22Article in journal (Refereed)
    Abstract [en]

    Background: Cardiac time intervals have been described as a measure of cardiac performance, where prolongation, shortening and delay of the different time intervals have been evaluated as markers of cardiac dysfunction. A relatively recently developed method with improved ability to measure cardiac events is Tissue Doppler Imaging (TDI), allowing accurate measurement of myocardial movements. Methods: We propose the state diagram of the heart as a new visualization tool for cardiac time intervals, presenting comparative, normalized data of systolic and diastolic performance, providing a more complete overview of cardiac function. This study aimed to test the feasibility of the state diagram method by presenting examples demonstrating its potential use in the clinical setting and by performing a clinical study, which included a comparison of the state diagram method with established echocardiography methods (E/E' ratio, LVEF and WMSI). The population in the clinical study consisted of seven patients with non ST-elevation myocardial infarction (NSTEMI) and seven control subjects, individually matched according to age and gender. The state diagram of the heart was generated from TDI curves from seven positions in the myocardium, visualizing the inter-and intraventricular function of the heart by displaying the cardiac phases. Results: The clinical examples demonstrated that the state diagram allows for an intuitive visualization of pathological patterns as ischemia and dyssynchrony. Further, significant differences in percentage duration between the control group and the NSTEMI group were found in eight of the totally twenty phases (10 phases for each ventricle), e.g. in the transition phases (Pre-Ejection and Post-Ejection). These phases were significantly longer (> 2.18%) for the NSTEMI group than for the control group (p < 0.05). No significant differences between the groups were found for the established echocardiography methods. Conclusion: The test results clearly indicate that the state diagram has potential to be an efficient tool for visualization of cardiac dysfunction and for detection of NSTEMI.

  • 32.
    Manouras, Aristomenis
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Shahgaldi, Kambiz
    Winter, Reidar
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Nowak, Jacek
    Measurements of left ventricular myocardial longitudinal systolic displacement using spectral and colour tissue Doppler: time for a reassessment?2009In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 7, p. 12-Article in journal (Refereed)
    Abstract [en]

    Background: Echocardiographic measurements of left ventricular (LV) myocardial displacement may produce different results depending on the choice of employed modality and subjective adjustments during data acquisition and analysis. Methods: In this study, left ventricular longitudinal systolic displacement was quantified in 57 patients (31 women and 26 men, 50 +/- 16 years) using colour (colour TD) and spectral tissue Doppler (spectral TD) before and after temporal filtering (30 to 70 milliseconds in 20-millisecond steps) and changed offline gain saturation (0%, 50% and 100%), respectively. The results were compared with those obtained with anatomic M-mode. Results: Whereas only minor differences occurred between the results of colour TD and anatomic M-mode measurements, spectral TD significantly overestimated the results obtained with both these methods. However, the limits of agreement between the results produced by all three studied methods were not clinically acceptable in any of the cases. The spectral TD displacement values increased along with increasing offline gain saturation whereas the effect of temporal filtering on colour Doppler measurements was insignificant. Conclusion: Measurements of LV myocardial longitudinal displacement employing spectral TD, colour TD or anatomic M-mode produce different results, thus discouraging interchangeable use of these modalities. Whereas the results of spectral TD measurements can be significantly altered by changing offline gain setting, the effect of temporal filtering on colour TD measurements is insignificant, a fact that increases clinical practicality of the latter method.

  • 33.
    Manouras, Aristomenis
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Shala, Arben
    Nyktari, Evangelia
    Shahgaldi, Kambiz
    Winter, Reidar
    Vardas, Panagiotis
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Nowak, Jacek
    Are measurements of systolic myocardial velocities and displacement with colour and spectral Tissue Doppler compatible?2009In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 7, p. 29-Article in journal (Refereed)
    Abstract [en]

    Background: Tissue Doppler (TD) in pulsed mode (spectral TD) and colour TD are the two modalities today available in tissue velocity echocardiography (TVE). Previous studies have shown poor agreement between these two methods when measuring myocardial velocities and displacement. In this study, the concordance between the myocardial velocity and displacement measurements using colour TD and different spectral TD procedures was evaluated. Methods: Left ventricular (LV) longitudinal systolic myocardial velocities and displacement during ejection period were quantified at the basal septal and lateral wall in 24 healthy individuals (4 women and 20 men, 34 +/- 12 years) using spectral TD, colour TD and M-mode recordings. Mean, maximal and minimal spectral TD systolic velocities and the corresponding displacement values were obtained by measurements at the outer and inner borders of the spectral velocity signal. The results were then compared with those obtained with the two other modalities used. Results: Systolic myocardial velocities derived from mean spectral TD frequencies were highly concordant with corresponding colour TD measurements (mean difference 0.10 +/- 0.54 cm/sec in septal and 0.09 +/- 0.97 cm/sec in lateral wall). Similarly, the agreement between spectral and colour TD (mean difference 0.22 +/- 0.74 mm in septal and 0.02 +/- 0.86 mm in lateral wall) as well as M-mode was good when mean spectral velocities were temporally integrated and the results did not differ statistically. Conversely, displacement values from the inner or outer border of the spectral signal differed significantly from values obtained with colour TD and M-mode (p < 0.001, in both cases). Conclusion: LV systolic myocardial measurements based on mean spectral TD frequencies are highly concordant with those provided by colour TD and M-mode. Hence, in order to maintain compatibility of the results, the use of this particular spectral TD procedure should be advocated in clinical praxis.

  • 34.
    Maret, Eva
    et al.
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Brudin, Lars
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Lindström, Lena
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Nylander, Eva
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ohlsson, Jan L
    Ryhov City Hospital, Jönköping, Sweden.
    Engvall, Jan
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Computer-assisted determination of left ventricular endocardial borders reduces variability in the echocardiographic assessment of ejection fraction2008In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 6, no 55Article in journal (Refereed)
    Abstract [en]

    Background: Left ventricular size and function are important prognostic factors in heart disease. Their measurement is the most frequent reason for sending patients to the echo lab. These measurements have important implications for therapy but are sensitive to the skill of the operator. Earlier automated echo-based methods have not become widely used. The aim of our study was to evaluate an automatic echocardiographic method (with manual correction if needed) for determining left ventricular ejection fraction (LVEF) based on an active appearance model of the left ventricle (syngo (R) AutoEF, Siemens Medical Solutions). Comparisons were made with manual planimetry (manual Simpson), visual assessment and automatically determined LVEF from quantitative myocardial gated single photon emission computed tomography (SPECT).

    Methods: 60 consecutive patients referred for myocardial perfusion imaging (MPI) were included in the study. Two-dimensional echocardiography was performed within one hour of MPI at rest. Image quality did not constitute an exclusion criterion. Analysis was performed by five experienced observers and by two novices.

    Results: LVEF (%), end-diastolic and end-systolic volume/BSA (ml/m(2)) were for uncorrected AutoEF 54 +/- 10, 51 +/- 16, 24 +/- 13, for corrected AutoEF 53 +/- 10, 53 +/- 18, 26 +/- 14, for manual Simpson 51 +/- 11, 56 +/- 20, 28 +/- 15, and for MPI 52 +/- 12, 67 +/- 26, 35 +/- 23. The required time for analysis was significantly different for all four echocardiographic methods and was for uncorrected AutoEF 79 +/- 5 s, for corrected AutoEF 159 +/- 46 s, for manual Simpson 177 +/- 66 s, and for visual assessment 33 +/- 14 s. Compared with the expert manual Simpson, limits of agreement for novice corrected AutoEF was lower than for novice manual Simpson (0.8 +/- 10.5 vs. -3.2 +/- 11.4 LVEF percentage points). Calculated for experts and with LVEF (%) categorized into < 30, 30-44, 45-54 and >= 55, kappa measure of agreement was moderate (0.44-0.53) for all method comparisons (uncorrected AutoEF not evaluated).

    Conclusion: Corrected AutoEF reduces the variation in measurements compared with manual planimetry, without increasing the time required. The method seems especially suited for unexperienced readers.

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  • 35.
    Maret, Eva
    et al.
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Engvall, Jan
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Nylander, Eva
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Ohlsson, Jan
    1Department of Clinical Physiology, Ryhov County Hospital, SE-551 85 Jönköping, Sweden.
    Feasibility and diagnostic power of transthoracic coronary Doppler for coronary flow velocity reserve in patients referred for myocardial perfusion imaging2008In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 6, no 12Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Myocardial perfusion imaging (MPI), using single photon emission computed tomography (SPECT) is a validated method for detecting coronary artery disease. Transthoracic Doppler echocardiography (TTDE) of flow at rest and during adenosine provocation has previously been evaluated in selected patient groups. We therefore wanted to compare the diagnostic ability of TTDE in the left anterior descending coronary artery (LAD) to that of MPI in an unselected population of patients with chest pain referred for MPI. Our hypothesis was that TTDE with high accuracy would identify healthy individuals and exclude them from the need for further studies, enabling invasive investigations to be reserved for patients with a high probability of disease.

    METHODS: Sixty-nine patients, 44 men and 25 women, age 61 +/- 10 years (range 35-82), with a clinical suspicion of stress induced myocardial ischemia, were investigated. TTDE was performed at rest and during adenosine stress for myocardial scintigraphy.

    RESULTS: We found that coronary flow velocity reserve (CFVR) determined from diastolic measurements separated normal from abnormal MPI findings with statistical significance. TTDE identified coronary artery disease, defined from MPI, as reversible ischemia and/or permanent defect, with a sensitivity of 60% and a specificity of 79%. The positive predictive value was 43% and the negative predictive value was 88%. There was an overlap between groups which could be due to abnormal endothelial function in patients with normal myocardial perfusion having either hypertension or diabetes.

    CONCLUSION: TTDE is an attractive non-invasive method to evaluate chest pain without the use of isotopes, but the diagnostic power is strongly dependent on the population investigated. Even in our heterogeneous clinical cardiac population, we found that CFVR>2 in the LAD excluded significant coronary artery disease detected by MPI.

  • 36.
    Maret, Eva
    et al.
    Linköping University, Department of Biomedical Engineering, Center for Medical Image Science and Visualization. Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences.
    Tödt, Tim
    Linköping University, Department of Medical and Health Sciences, Cardiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology. Linköping University, Faculty of Health Sciences.
    Brudin, Lars
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences.
    Nylander, Eva
    Linköping University, Department of Medical and Health Sciences, Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Swahn, Eva
    Östergötlands Läns Landsting, Heart Centre, Department of Cardiology. Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences.
    Ohlsson, Jan
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences.
    Engvall, Jan
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Functional measurements based on feature tracking of cine magnetic resonance images identify left ventricular segments with myocardial scar.2009In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 7, no 53, p. 1-14Article in journal (Refereed)
    Abstract [en]

    Background

    The aim of the study was to perform a feature tracking analysis on cine magnetic resonance (MR) images to elucidate if functional measurements of the motion of the left ventricular wall may detect scar defined with gadolinium enhanced MR.

    Myocardial contraction can be measured in terms of the velocity, displacement and local deformation (strain) of a particular myocardial segment. Contraction of the myocardial wall will be reduced in the presence of scar and as a consequence of reduced myocardial blood flow.

    Methods

    Thirty patients (3 women and 27 men) were selected based on the presence or absence of extensive scar in the anteroseptal area of the left ventricle. The patients were investigated in stable clinical condition, 4-8 weeks post ST-elevation myocardial infarction treated with percutaneous coronary intervention. Seventeen had a scar area >75% in at least one anteroseptal segment (scar) and thirteen had scar area <1% (non-scar). Velocity, displacement and strain were calculated in the longitudinal direction, tangential to the endocardial outline, and in the radial direction, perpendicular to the tangent.

    Results

    In the scar patients, segments with scar showed lower functional measurements than remote segments. Radial measurements of velocity, displacement and strain performed better in terms of receiver-operator-characteristic curves (ROC) than the corresponding longitudinal measurements. The best area-under-curve was for radial strain, 0.89, where a cut-off value of 38.8% had 80% sensitivity and 86% specificity for the detection of a segment with scar area >50%. As a percentage of the mean, intraobserver variability was 16-14-26% for radial measurements of displacement-velocity-strain and corresponding interobserver variability was 13-12-18%.

    Conclusion

    Feature tracking analysis of cine-MR displays velocity, displacement and strain in the radial and longitudinal direction and may be used for the detection of transmural scar. The accuracy and repeatability of the radial functional measurements is satisfactory and global measures agree.

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  • 37.
    Mårtensson, Mattias
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Winter, Reidar
    Cederlund, Kerstin
    Ripsweden, Jonaz
    Mir-Akbari, Habib
    Nowak, Jacek
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Assessment of left ventricular volumes using simplified 3-D echocardiography and computed tomography - a phantom and clinical study2008In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 6Article in journal (Refereed)
    Abstract [en]

    Objectives: To compare the accuracy of simplified 3-dimensional (3-D) echocardiography vs. multi-slice computed tomography (MSCT) software for the quantification of left ventricular (LV) volumes. Design: Three-D echocardiography (3-planes approach) and MSCT-CardIQ software were calibrated by measuring known volumes of 10 phantoms designed to closely mimic blood-endocardium interface. Subsequently, LV volumes were measured with both the methods in 9 patients referred routinely for coronary angiography and the agreement between the measurements was evaluated. Results: Simplified 3D-echocardiography provided higher degree of agreement between the measured and true phantom volumes (mean difference 0 +/- 1 ml, variation range + 4 to -4 ml) than MSCT software (mean difference 6 +/- 5 ml; variation range + 22 to -10 ml). The agreement between LV measurements in the patients was considerably poorer, with significantly larger volumes produced by MSCT (mean difference - 23 +/- 40 ml, variation between + 93 and -138 ml). Conclusion: Simplified 3-D echocardiography provides more accurate assessment of phantom volumes than MSCT-CardIQ software. The discrepancy between the results of LV measurements with the two methods is even greater and does not warrant their interchangeable diagnostic use.

  • 38. Quintana, Miguel
    et al.
    Lindell, Peter
    Saha, Samir K
    del Furia, Francesca
    Lind, Britta
    Department of Clinical Physiology, Karolinska University Hospital.
    Govind, Satish
    Brodin, Lars-Ake
    Department of Clinical Physiology, Karolinska University Hospital.
    Assessment of atrial regional and global electromechanical function by tissue velocity echocardiography: a feasibility study on healthy individuals2005In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 3, no 18 February 2005Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: The appropriate evaluation of atrial electrical function is only possible by means of invasive electrophysiology techniques, which are expensive and therefore not suitable for widespread use. Mechanical atrial function is mainly determined from atrial volumes and volume-derived indices that are load-dependent, time-consuming and difficult to reproduce because they are observer-dependent.

    AIMS: To assess the feasibility of tissue velocity echocardiography (TVE) to evaluate atrial electromechanical function in young, healthy volunteers.

    SUBJECTS AND METHODS: We studied 37 healthy individuals: 28 men and nine women with a mean age of 29 years (range 20-47). Standard two-dimensional (2-D) and Doppler echocardiograms with superimposed TVE images were performed. Standard echocardiographic images were digitized during three consecutive cardiac cycles in cine-loop format for off-line analysis. Several indices of regional atrial electrical and mechanical function were derived from both 2-D and TVE modalities.

    RESULTS: Some TVE-derived variables indirectly reflected the atrial electrical activation that follows the known activation process as revealed by invasive electrophysiology. Regionally, the atrium shows an upward movement of its walls at the region near the atrio-ventricular ring with a reduction of this movement towards the upper levels of the atrial walls. The atrial mechanical function as assessed by several TVE-derived indices was quite similar in all left atrium (LA) walls. However, all such indices were higher in the right (RA) than the LA. There were no correlations between the 2-D- and TVE-derived variables expressing atrial mechanical function. Values of measurement error and repeatability were good for atrial mechanical function, but only acceptable for atrial electrical function.

    CONCLUSION: TVE may provide a simple, easy to obtain, reproducible, repeatable and potentially clinically useful tool for quantifying atrial electromechanical function.

  • 39. Quintana, Miguel
    et al.
    Saha, Samir
    Govind, Satish
    Brodin, Lars-Åke
    Karolinska University Hospital, Huddinge, Stockholm, Sweden.
    del Furia, Francesca
    Bertomeu, Vicente
    Cardiac incoordination induced by left bundle branch block: its relation with left ventricular systolic function in patients with and without cardiomyopathy2008In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 6Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Although left bundle branch block (LBBB) alters the electrical activation of the heart, it is unknown how it might change the process of myocardial coordination (MC) and how it may affect the left ventricular (LV) systolic function. The present study assessed the effects of LBBB on MC in patients with LBBB with and without dilated (DCMP) or ischemic cardiomyopathy (ICMP).

    METHODS: Tissue Doppler echocardiography (TDE) was performed in 86 individuals: 21 with isolated LBBB, 26 patients with DCMP + LBBB, 19 patients with ICMP + LBBB and in 20 healthy individuals (Controls). MC was assessed analyzing the myocardial velocity profiles obtained from six basal segments of the LV using TDE. The LV systolic function was assessed by standard two-dimensional echocardiography and by TDE.

    RESULTS: Severe alterations in MC were observed in subjects with LBBB as compared with controls (P < 0.01 for all comparisons); these derangements were even worse in patients with DCMP and ICMP (P < 0.001 for comparisons with Controls and P < 0.01 for comparison with individuals with isolated LBBB). Some parameters of MC differed significantly between DCMP and ICMP (P < 0.01). A good or very good correlation coefficient was found between variables of MC and variables of LV systolic function.

    CONCLUSION: LBBB induces severe derangement in the process of MC that are more pronounced in patients with cardiomyopathies and that significantly correlates with the LV systolic function. The assessment of MC may help in the evaluation of the etiology of dilated cardiomyopathy.

  • 40.
    Rosendahl, Lene
    et al.
    Department of Clinical Physiology, Ryhov County Hospital, Jönköping, Sweden; Center for Medical Image Science and Visualization, CMIV, Linköping University Hospital, Linköping, Sweden.
    Blomstrand, Peter
    Department of Clinical Physiology, Ryhov County Hospital, Jönköping, Sweden.
    Brudin, Lars
    Department of Clinical Physiology, Kalmar County Hospital, Kalmar, Sweden; Department of Medical and Health Sciences, Linköping University Hospital, Linköping, Sweden.
    Tödt, Tim
    Department of Medical and Health Sciences/CVM, Division of Cardiology, Linköping University Hospital, Linköping, Sweden.
    Engvall, Jan E.
    Center for Medical Image Science and Visualization, CMIV, Linköping University Hospital, Linköping, Sweden; Department of Medical and Health Sciences/CVM, Division of Clinical Physiology, Linköping University Hospital, Linköping, Sweden.
    Longitudinal peak strain detects a smaller risk area than visual assessment of wall motion in acute myocardial infarction2010In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 8, no 1, article id 2Article in journal (Refereed)
    Abstract [en]

    Background. Opening of an occluded infarct related artery reduces infarct size and improves survival in acute ST-elevation myocardial infarction (STEMI). In this study we performed tissue Doppler analysis (peak strain, displacement, mitral annular movement (MAM)) and compared with visual assessment for the study of the correlation of measurements of global, regional and segmental function with final infarct size and transmurality. In addition, myocardial risk area was determined and a prediction sought for the development of infarct transmurality 50%.

    Methods. Twenty six patients with STEMI submitted for primary percutaneous coronary intervention (PCI) were examined with echocardiography on the catheterization table. Four to eight weeks later repeat echocardiography was performed for reassessment of function and magnetic resonance imaging for the determination of final infarct size and transmurality.

    Results. On a global level, wall motion score index (WMSI), ejection fraction (EF), strain, and displacement all showed significant differences (p ≤ 0.001, p ≤ 0.001, p ≤ 0.001 and p = 0.03) between the two study visits, but MAM did not (p = 0.17). On all levels (global, regional and segmental) and both pre- and post PCI, WMSI showed a higher correlation with scar transmurality compared to strain. We found that both strain and WMSI predicted the development of scar transmurality 50%, but strain added no significant information to that obtained with WMSI in a logistic regression analysis.

    Conclusions. In patients with acute STEMI, WMSI, EF, strain, and displacement showed significant changes between the pre- and post PCI exam. In a ROC-analysis, strain had 64% sensitivity at 80% specificity and WMSI around 90% sensitivity at 80% specificity for the detection of scar with transmurality 50% at follow-up. 

  • 41.
    Rosendahl, Lene
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Blomstrand, Peter
    Department of Clinical Physiology, Ryhov County Hospital, Jönköping, Sweden.
    Brudin, Lars
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Tödt, Tim
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences.
    Engvall, Jan E
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Longitudinal peak strain detects a smaller risk area than visual assessment of wall motion in acute myocardial infarction2010In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 8, no 2, p. 1-12Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Opening of an occluded infarct related artery reduces infarct size and improves survival in acute ST-elevation myocardial infarction (STEMI). In this study we performed tissue Doppler analysis (peak strain, displacement, mitral annular movement (MAM)) and compared with visual assessment for the study of the correlation of measurements of global, regional and segmental function with final infarct size and transmurality. In addition, myocardial risk area was determined and a prediction sought for the development of infarct transmurality >or=50%.

    METHODS: Twenty six patients with STEMI submitted for primary percutaneous coronary intervention (PCI) were examined with echocardiography on the catheterization table. Four to eight weeks later repeat echocardiography was performed for reassessment of function and magnetic resonance imaging for the determination of final infarct size and transmurality.

    RESULTS: On a global level, wall motion score index (WMSI), ejection fraction (EF), strain, and displacement all showed significant differences (p or=50%, but strain added no significant information to that obtained with WMSI in a logistic regression analysis.

    CONCLUSIONS: In patients with acute STEMI, WMSI, EF, strain, and displacement showed significant changes between the pre- and post PCI exam. In a ROC-analysis, strain had 64% sensitivity at 80% specificity and WMSI around 90% sensitivity at 80% specificity for the detection of scar with transmurality >or=50% at follow-up.

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  • 42. Sadigh, Bita
    et al.
    Quintana, Miguel
    Sylvén, Christer
    Berglund, Margareta
    Brodin, Lars Åke
    Institution of Laboratory Medicine, Karolinska University Hospital, Huddinge, Stockholm, Sweden.
    The ischemic preconditioning effect of adenosine in patients with ischemic heart disease2009In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 7Article in journal (Refereed)
    Abstract [en]

    INTRODUCTION: In vivo and in vitro evidence suggests that adenosine and its agonists play key roles in the process of ischemic preconditioning. The effects of low-dose adenosine infusion on ischemic preconditioning have not been thoroughly studied in humans.

    AIMS: We hypothesised that a low-dose adenosine infusion could reduce the ischemic burden evoked by physical exercise and improve the regional left ventricular (LV) systolic function.

    MATERIALS AND METHODS: We studied nine severely symptomatic male patients with severe coronary artery disease. Myocardial ischemia was induced by exercise on two separate occasions and quantified by Tissue Doppler Echocardiography. Prior to the exercise test, intravenous low-dose adenosine or placebo was infused over ten minutes according to a randomized, double blind, cross-over protocol. The LV walls were defined as ischemic if a reduction, no increment, or an increment of < 15% in peak systolic velocity (PSV) was observed during maximal exercise compared to the baseline values observed prior to placebo-infusion. Otherwise, the LV walls were defined as non-ischemic.

    RESULTS: PSV increased from baseline to maximal exercise in non-ischemic walls both during placebo (P = 0.0001) and low-dose adenosine infusion (P = 0.0009). However, in the ischemic walls, PSV increased only during low-dose adenosine infusion (P = 0.001), while no changes in PSV occurred during placebo infusion (P = NS).

    CONCLUSION: Low-dose adenosine infusion reduced the ischemic burden and improved LV regional systolic function in the ischemic walls of patients with exercise-induced myocardial ischemia, confirming that adenosine is a potential preconditioning agent in humans.

  • 43.
    Shahgaldi, Kambiz
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    da Silva, Cristina
    KTH, School of Technology and Health (STH).
    Bäck, Magnus
    Rück, Andreas
    Manouras, Aristomenis
    KTH, School of Technology and Health (STH), Medical Engineering.
    Sahlén, Anders
    Transesophageal echocardiography measurements of aortic annulus diameter using biplane mode in patients undergoing transcatheter aortic valve implantation2013In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 11, no 1, p. 5-Article in journal (Refereed)
    Abstract [en]

    Background: Aortic stenosis (AS) is a relevant common valve disorder. Severe AS and symptoms and/or left ventricular dysfunction (EF<50%) have the indication for aortic valve replacement (AVR). Majority of the patients with AS are elderly often with co-morbidities and generally have high preoperative risk. Transcatheter aortic valve implantation (TAVI) is offered in this group. Four different sizes of Corevalve prosthesis are available. Correct measurement of aortic size prior to TAVI is of great important to choose the right prosthesis size to avoid among others paravalvular leak or prosthesis patient mismatch. Aim of the study is to assess the aortic annulus diameter in patients undergoing TAVI by biplane (BP) mode using transesophageal echocardiography (TEE) and compare it to two-dimensional (2D) transthoracic echocardiography (TTE) and 2DTEE using three-dimensional (3D) TEE as reference method. Methods: The study population consisted of 50 patients retrospectively (24 men and 26 women, mean age 85 +/- 8 years of age) who all had undergone echocardiography examination prior to TAVI. Results: The mean aortic annulus diameter was 20.4 +/- 2.2 mm with TTE, 22.3 +/- 2.5 mm with 2DTEE, 22.9 +/- 1.9 mm with BP-mode and 23.1 +/- 1.9 mm with 3DTEE. TTE underestimated the mean aortic annulus diameter in comparison to transesophageal imaging modalities (p<0.001). Using 3DTEE, 2% of patients were unsuitable for TAVI due to a too-small AoA (n=1). This figure was similar with BP (4%, n=2; p=1.00) but considerably larger with 2DTTE (36%, n=18; p<0.001) and 2DTEE (12%, n=6; p=0.06). There was a strong correlation between BP-mode and 3DTEE for assessment of aortic annulus diameter (r-value 0.88) with small mean difference (-0.2 +/- 0.9 mm) whereas the other modalities showed larger 95% confidence interval and modest correlation (2DTTE vs. 3DTEE, -6.3 to 0.9 mm, r=0.64 and 2DTEE vs. 3DTEE, -4.8 to 3.2 mm, r=0.61). Conclusion: A multi-dimensional method is preferred to assess aortic annulus diameter in TAVI patients since there is risk of underestimation using single plane. Biplane mode is the method of choice in view of speedy post-processing with no need for expensive dedicated software. Lastly, single plane methods lead to misclassification of patients as unsuitable for TAVI. This may be of major clinical importance.

  • 44. Shahgaldi, Kambiz
    et al.
    Gudmundsson, Petri
    Manouras, Aristomenis
    Brodin, Lars-Ake
    KTH, School of Technology and Health (STH), Medical Engineering.
    Winter, Reidar
    Visually estimated ejection fraction by two dimensional and triplane echocardiography is closely correlated with quantitative ejection fraction by real-time three dimensional echocardiography2009In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 7Article in journal (Refereed)
    Abstract [en]

    Background: Visual assessment of left ventricular ejection fraction (LVEF) is often used in clinical routine despite general recommendations to use quantitative biplane Simpsons (BPS) measurements. Even thou quantitative methods are well validated and from many reasons preferable, the feasibility of visual assessment (eyeballing) is superior. There is to date only sparse data comparing visual EF assessment in comparison to quantitative methods available. The aim of this study was to compare visual EF assessment by two-dimensional echocardiography (2DE) and triplane echocardiography (TPE) using quantitative real-time three-dimensional echocardiography (RT3DE) as the reference method.

    Methods: Thirty patients were enrolled in the study. Eyeballing EF was assessed using apical 4-and 2 chamber views and TP mode by two experienced readers blinded to all clinical data. The measurements were compared to quantitative RT3DE.

    Results: There were an excellent correlation between eyeballing EF by 2D and TP vs 3DE (r = 0.91 and 0.95 respectively) without any significant bias (-0.5 +/- 3.7% and -0.2 +/- 2.9% respectively). Intraobserver variability was 3.8% for eyeballing 2DE, 3.2% for eyeballing TP and 2.3% for quantitative 3D-EF. Interobserver variability was 7.5% for eyeballing 2D and 8.4% for eyeballing TP.

    Conclusion: Visual estimation of LVEF both using 2D and TP by an experienced reader correlates well with quantitative EF determined by RT3DE. There is an apparent trend towards a smaller variability using TP in comparison to 2D, this was however not statistically significant.

  • 45. Shahgaldi, Kambiz
    et al.
    Gudmundsson, Petri
    Malmö högskola, Faculty of Health and Society (HS).
    Manouras, Aristomenis
    Brodin, Lars-Åke
    Winter, Reidar
    Visually estimated ejection fraction by two dimensional and triplane echocardiography is closely correlated with quantitative ejection fraction by real-time three dimensional echocardiography2009In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 7, article id 41Article in journal (Refereed)
    Abstract [en]

    Background: Visual assessment of left ventricular ejection fraction (LVEF) is often used in clinical routine despite general recommendations to use quantitative biplane Simpsons (BPS) measurements. Even thou quantitative methods are well validated and from many reasons preferable, the feasibility of visual assessment (eyeballing) is superior. There is to date only sparse data comparing visual EF assessment in comparison to quantitative methods available. The aim of this study was to compare visual EF assessment by two-dimensional echocardiography (2DE) and triplane echocardiography (TPE) using quantitative real-time three-dimensional echocardiography (RT3DE) as the reference method. Methods: Thirty patients were enrolled in the study. Eyeballing EF was assessed using apical 4-and 2 chamber views and TP mode by two experienced readers blinded to all clinical data. The measurements were compared to quantitative RT3DE. Results: There were an excellent correlation between eyeballing EF by 2D and TP vs 3DE (r = 0.91 and 0.95 respectively) without any significant bias (-0.5 ± 3.7% and -0.2 ± 2.9% respectively). Intraobserver variability was 3.8% for eyeballing 2DE, 3.2% for eyeballing TP and 2.3% for quantitative 3D-EF. Interobserver variability was 7.5% for eyeballing 2D and 8.4% for eyeballing TP. Conclusion: Visual estimation of LVEF both using 2D and TP by an experienced reader correlates well with quantitative EF determined by RT3DE. There is an apparent trend towards a smaller variability using TP in comparison to 2D, this was however not statistically significant.

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  • 46. Shahgaldi, Kambiz
    et al.
    Manouras, Aristomenis
    Abrahamsson, Anna
    Gudmundsson, Petri
    Malmö högskola, Faculty of Health and Society (HS).
    Brodin, Lars-Åke
    Winter, Reidar
    Three-dimensional echocardiography using single-heartbeat modality decreases variability in measuring left ventricular volumes and function in comparison to four-beat technique in atrial fibrillation2010In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 8, article id 45Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Three dimensional echocardiography (3DE) approaches the accuracy of cardiac magnetic resonance in measuring left ventricular (LV) volumes and ejection fraction (EF). The multibeat modality in comparison to single-beat (SB) requires breath-hold technique and regular heart rhythm which could limit the use of this technique in patients with atrial fibrillation (AF) due to stitching artifact. The study aimed to investigate whether SB full volume 3DE acquisition reduces inter- and intraobserver variability in assessment of LV volumes and EF in comparison to four-beat (4B) ECG-gated full volume 3DE recording in patients with AF. METHODS: A total of 78 patients were included in this study. Fifty-five with sinus rhythm (group A) and 23 having AF (group B). 4B and SB 3DE was performed in all patients. LV volumes and EF was determined by these two modalities and inter- and intraobserver variability was analyzed. RESULTS: SB modality showed significantly lower inter- and intraobserver variability in group B in comparison to 4B when measuring LV volumes and EF, except for end-systolic volume (ESV) in intraobserver analysis. There were significant differences when calculating the LV volumes (p<0.001) and EF (p<0.05) with SB in comparison to 4B in group B. CONCLUSION: Single-beat three-dimensional full volume acquisition seems to be superior to four-beat ECG-gated acquisition in measuring left ventricular volumes and ejection fraction in patients having atrial fibrillation. The variability is significantly lower both for ejection fraction and left ventricular volumes.

  • 47.
    Shahgaldi, Kambiz
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Manouras, Aristomenis
    KTH, School of Technology and Health (STH), Medical Engineering.
    Abrahamsson, Anna
    Gudmundsson, Petri
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Winter, Reidar
    Three-dimensional echocardiography using single-heartbeat modality decreases variability in measuring left ventricular volumes and function in comparison to four-beat technique in atrial fibrillation2010In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 8, no 1Article in journal (Refereed)
    Abstract [en]

    Background: Three dimensional echocardiography (3DE) approaches the accuracy of cardiac magnetic resonance in measuring left ventricular (LV) volumes and ejection fraction (EF). The multibeat modality in comparison to single-beat (SB) requires breath-hold technique and regular heart rhythm which could limit the use of this technique in patients with atrial fibrillation (AF) due to stitching artifact. The study aimed to investigate whether SB full volume 3DE acquisition reduces inter-and intraobserver variability in assessment of LV volumes and EF in comparison to four-beat (4B) ECG-gated full volume 3DE recording in patients with AF.

    Methods: A total of 78 patients were included in this study. Fifty-five with sinus rhythm (group A) and 23 having AF (group B). 4B and SB 3DE was performed in all patients. LV volumes and EF was determined by these two modalities and inter-and intraobserver variability was analyzed.

    Results: SB modality showed significantly lower inter-and intraobserver variability in group B in comparison to 4B when measuring LV volumes and EF, except for end-systolic volume (ESV) in intraobserver analysis. There were significant differences when calculating the LV volumes (p < 0.001) and EF (p < 0.05) with SB in comparison to 4B in group B.

    Conclusion: Single-beat three-dimensional full volume acquisition seems to be superior to four-beat ECG-gated acquisition in measuring left ventricular volumes and ejection fraction in patients having atrial fibrillation. The variability is significantly lower both for ejection fraction and left ventricular volumes.

  • 48. Shahgaldi, Kambiz
    et al.
    Söderqvist, Emil
    Gudmundsson, Petri
    Malmö högskola, Faculty of Health and Society (HS).
    Winter, Reidar
    Nowak, Jacek
    Brodin, Lars-Åke
    Flow-volume loops derived from three-dimensional echocardiography: a novel approach to the assessment of left ventricular hemodynamics2008In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 6Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: This study explores the feasibility of non-invasive evaluation of left ventricular (LV) flow-volume dynamics using 3-dimensional (3D) echocardiography, and the capacity of such an approach to identify altered LV hemodynamic states caused by valvular abnormalities. METHODS: Thirty-one patients with moderate-severe aortic (AS) and mitral (MS) stenoses (21 and 10 patients, respectively) and 10 healthy volunteers underwent 3D echocardiography with full volume acquisition using Philips Sonos 7500 equipment. The digital 3D data were post- processed using TomTec software. LV flow-volume loops were subsequently constructed for each subject by plotting instantaneous LV volume data sampled throughout the cardiac cycle vs. their first derivative representing LV flow. After correction for body surface area, an average flow-volume loop was calculated for each subject group. RESULTS: Flow-volume loops were obtainable in all subjects, except 3 patients with AS. The flow-volume diagrams displayed clear differences in the form and position of the loops between normal individuals and the respective patient groups. In patients with AS, an "obstructive" pattern was observed, with lower flow values during early systole and larger end-systolic volume. On the other hand, patients with MS displayed a "restrictive" flow-volume pattern, with reduced diastolic filling and smaller end-diastolic volume. CONCLUSION: Non-invasive evaluation of LV flow-volume dynamics using 3D-echocardiographic data is technically possible and the approach has a capacity to identify certain specific types of alteration of LV flow-volume pattern caused by valvular abnormalities, thus reflecting underlying hemodynamic states specific for these abnormalities.

  • 49. Shahgaldi, Kambiz
    et al.
    Söderqvist, Emil
    Gudmundsson, Petri
    Winter, Reidar
    Nowak, Jacek
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Flow-volume loops derived from three-dimensional echocardiography: a novel approach to the assessment of left ventricular hemodynamics2008In: Cardiovascular Ultrasound, E-ISSN 1476-7120, Vol. 6Article in journal (Refereed)
    Abstract [en]

    Background: This study explores the feasibility of non-invasive evaluation of left ventricular (LV) flow-volume dynamics using 3-dimensional (3D) echocardiography, and the capacity of such an approach to identify altered LV hemodynamic states caused by valvular abnormalities.

    Methods: Thirty-one patients with moderate-severe aortic (AS) and mitral (MS) stenoses (21 and 10 patients, respectively) and 10 healthy volunteers underwent 3D echocardiography with full volume acquisition using Philips Sonos 7500 equipment. The digital 3D data were post-processed using TomTec software. LV flow-volume loops were subsequently constructed for each subject by plotting instantaneous LV volume data sampled throughout the cardiac cycle vs. their first derivative representing LV flow. After correction for body surface area, an average flow-volume loop was calculated for each subject group.

    Results: Flow-volume loops were obtainable in all subjects, except 3 patients with AS. The flow-volume diagrams displayed clear differences in the form and position of the loops between normal individuals and the respective patient groups. In patients with AS, an "obstructive" pattern was observed, with lower flow values during early systole and larger end-systolic volume. On the other hand, patients with MS displayed a "restrictive" flow-volume pattern, with reduced diastolic filling and smaller end-diastolic volume.

    Conclusion: Non-invasive evaluation of LV flow-volume dynamics using 3D-echocardiographic data is technically possible and the approach has a capacity to identify certain specific types of alteration of LV flow-volume pattern caused by valvular abnormalities, thus reflecting underlying hemodynamic states specific for these abnormalities.

  • 50.
    Söderqvist, Emil
    et al.
    Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
    Cain, Peter
    Lind, Britta
    Division of Clinical Physiology, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
    Winter, Reidar
    Nowak, Jacek
    Brodin, Lars-Åke
    Division of Clinical Physiology, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
    Feasibility of creating estimates of left ventricular flow-volume dynamics using echocardiography2006In: Cardiovascular Ultrasound, E-ISSN 1476-7120, no 4:40Article in journal (Refereed)
    Abstract [en]

    Background:This study explores the feasibility of non-invasive assessment of left ventricular volume and flow relationship throughout cardiac cycle employing echocardiographic methods.

    Methods:Nine healthy individuals and 3 patients with severe left-sided valvular abnormalities were subject to resting echocardiography with automated endocardial border detection allowing real-time estimation of left ventricular volume throughout the cardiac cycle. Global and regional (6 different left ventricular segments) estimates of flow-volume loops were subsequently constructed by plotting acquired instantaneous left ventricular 2-D area data (left ventricular volume) vs. their first derivatives (flow).

    Results:Flow-volume loop estimates were obtainable in 75% of all echocardiographic images and displayed in normal individuals some regional morphological variation with more pronounced isovolumic events in the paraseptal segments and significantly delayed maximal systolic flow paraapically. In patients with aortic stenosis, maximal systolic flow occurred at a lower estimated left ventricular systolic volume whereas in mitral stenosis, maximal diastolic flow was observed at a higher estimated left ventricular diastolic volume. Aortic regurgitation caused a complex alteration of the estimated flow-volume loop shape during diastole.

    Conclusion:Non-invasive assessment of left ventricular flow-volume relationship with echocardiography is technically feasible and reveals the existence of regional variation in flow-volume loop morphology. Valvular abnormalities cause a clear and specific alteration of the estimates of the normal systolic or diastolic flow-volume pattern, likely reflecting the underlying pathophysiology.

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