Coronary artery size and disease in UK South Asian and Caucasian men.

Objective: South Asian patients in the UK have a higher mortality rate after coronary artery bypass grafting (CABG) than Caucasian patients. As coronary artery size has been shown to correlate to outcome from bypass grafting, it has been suggested that smaller coronary arteries in South Asians as compared to Caucasians could contribute to a poorer outcome in the Asian population. We aimed to measure coronary artery size and disease in matched South Asian and Caucasian men undergoing first time coronary artery bypass grafting.

Methods: Coronary arteriograms from 53 matched first generation South Asian and Caucasian men were examined. The patients had no history of myocardial infarction, coronary revascularisation, familial dyslipidaemia, diabetes or renal disease. They were individually matched for age, height, weight, body mass index and body surface area. Thereafter, coronary artery diameters and significant (> or =50%) diameter stenoses were measured in a blinded fashion using quantitative coronary angiography (QCA).

Results: In South Asian men, diameters of the left main stem (LMS) and the proximal left anterior descending, the circumflex and the right coronary arteries were 4.6+/-0.9 mm, 3.5+/-0.8 mm, 3.4+/-0.8 mm and 3.5+/-0.8 mm, respectively. The corresponding arterial diameters among Caucasian men (4.5+/-0.9 mm, 3.5+/-0.7 mm, 3.5+/-0.8 mm and 3.8+/-0.8 mm) did not differ from those in South Asians. There was no difference in the number of significant coronary artery stenoses between the two groups and no difference in bypass and cross-clamp times or in adverse outcome (one from each group died after coronary artery bypass grafting).

Conclusion: Proximal coronary artery size and number of significant coronary stenoses did not differ between matched pairs of South Asian and Caucasian men using strict inclusion/exclusion criteria.