BACKGROUND: Ethnic differences in prevalence and severity of coronary artery disease are well established and are usually attributed to risk factors variation. This study investigates the differences in coronary artery narrowing and coronary calcification between two age- and gender-matched cohorts of South Asian and Caucasian symptomatic angina patients.

METHODS: We identified 101 symptomatic angina patients of South Asian origin who had undergone CT angiography and calcium scoring, and compared them with 101 age and gender matched Caucasian patients.

RESULTS: South Asians had a greater mean number of arterial segments with both obstructive and non-obstructive plaque than Caucasians (p=0.006 and p=0.0003, respectively) and higher prevalence of triple-vessel disease (p=0.0004). Similarly, South Asians had a higher mean CAC score (p<0.0001) and the percentage of South Asians with CAC>0 and in all categories of CAC score 100-1000 were also higher, as was the number of arterial segments with calcified and non-calcified plaque. These results were more marked in patients aged >50 but in those ≤50, Caucasians showed a higher mean number of diseased segments (p=0.019), with non-obstructive plaque (p=0.02), possibly suggesting that Caucasians are likely to have more diffuse atherosclerosis at an earlier age. CAC prevalence and severity in this age-group were not significantly different between South Asians and Caucasians.

CONCLUSION: Despite similar conventional risk factors for CAD, symptomatic South Asians seem to have more aggressive and diffuse arterial calcification compared to Caucasians. These differences are more profound above the age of 50, suggesting potential genetic or other risk factors yet to be determined.

BACKGROUND AND AIM: Coronary artery calcium score (CACs) is an established quantitative tool for assessing subclinical atherosclerosis. The aim of this study was to assess in a meta-analysis model the natural history and reproducibility of CACs measurements obtained from St Francis and EBEAT trials.

METHODS: We analysed data from 649 individuals: 443 on placebo with 2year follow-up from St Francis trial (Study A) and 209 on 10mg atorvastatin with 1year follow-up of EBEAT trial (Study B). Total CACs and that in the left coronary artery (LCA) branches, left main stem (LMS), left anterior descending (LAD), left circumflex (Cx) and right coronary artery (RCA) were analysed. In view of the wide CACs spectrum, data were logarithmically transformed before the analyses and mixed model analysis was used to evaluate the change of CACs over time.

RESULTS: The overall agreement between the two measurements was fairly good, showing a small but significant increase in CAC: 68% of the group as a whole presented an increase in CACs, 23% of the cohort had negligible change in CACs of <10% irrespective of the baseline CACs; and the remaining 10% showed a fall in CACs. Both studies showed similar patterns. The analysis of individual coronary arteries showed significantly higher variability of measurements in the RCA than in the LCA. Males had higher baseline CACs than females, but the rate of progression was not different between genders, irrespectively of age and baseline score.

CONCLUSION: The natural history of CACs was overtime progression in the majority of subjects, irrespective of gender. The higher variability in RCA measurements could be related to the low baseline CACs or exaggerated movement of the right side atrioventricular ring, whereas those for LCA branches are influenced by the branch allocation of the CACs. Large changes to and from zero, might be related to technical limitations.

AIM: To investigate the prevalence of coronary artery calcification (CAC) in symptomatic individuals with CT evidence for left heart valve calcification, aortic valve (AVC), mitral valve (MAC) or both.

METHODS: This is a retrospective study of 282 consecutive patients with calcification in either the aortic valve or mitral annulus. Calcium scoring of the coronary artery, aortic and mitral valve was measured using the Agatston score.

RESULTS: AVC was more prevalent than MAC (64% vs. 2.5%, p<0.001), with 34% having both. Absence of CAC was noted in 12.7% of the study population. AVC+CAC were observed in 53.5%, MAC and CAC in 2.1%, and combined AVC, MAC and CAC in 31.6%. The median CAC score was higher in individuals with combined AVC+MAC, followed by those with AVC and lowest was in the MAC group. The majority (40%) of individuals with AVC had CAC score >400, and only in 16% had CAC=0. The same pattern was more evident in individuals with AVC+MAC, where 70% had CAC score >400 and only 6% had CAC score of 0. These results were irrespective of gender. There was no correlation between AVC and MAC but there was modest correlation between CAC score and AVC score (r=0.28, p=0.0001), MAC (r=0.36, p=0.0001) and with combined AVC+MAC (r=0.5, p=0.0001). AVC score of 262 had a sensitivity of 78% and specificity of 92% for the prediction of presence of CAC.

CONCLUSION: The presence and extent of calcification in the aortic valve or/and mitral valves are associated with severe coronary artery calcification.