Association Between Common Carotid Intima - Media Thickness (Carotid Imt) and Coronary Artery Disease

Abstract

INTRODUCTION:The burden of coronary artery disease (CAD) continues to rise globally, as well as in India, recognizing sub clinical atherosclerosis is of paramount importance for prevention of CAD, stroke, and peripheral vascular disease. The early phase can be studied by two dimensional B-mode ultrasonography. This technique yields information on atherosclerotic wall changes that cannot be obtained by conventional angiography. Its non-invasive character and easy applicability make B-mode ultrasonography a powerful tool for measurement of the atherosclerotic burden. Carotid intima-media thickness (IMT) is defined as the intimal plus medial thickness as the distance between the leading edge of first echogenic line to the leading edge of second echogenic line on far wall of common carotid artery. AIM: To determine the association between carotid intimamedia thickness and coronary artery disease. METHODOLOGY: A total of 180 individuals (90 patients with coronary artery disease and 90 controls coming to the department of Cardiology, were studied. All individuals were subjected to clinical examination and investigations and relevant data was collected. Ultrasound scanning of the carotid arteries was performed as per ASE (American society of echocardiography) guidelines and common carotid intima-media thickness was measured. P value less than 0.05 was considered significant. RESULTS & CONCLUSIONS: Mean common carotid IMT in patients with established coronary artery disease was 0.86±0.17 mm and in persons without significant clinical coronary artery disease it was found to be 0.58±0.08 mm. Common carotid IMT was found to be higher in diabetes, hypertension, and those with high triglycerides and low HDL. There is no correlation between common carotid IMT with history of smoking total cholesterol or LDL cholesterol levels. Cut off value of 0.8m.m of common carotid intima-media thickness has a sensitivity of 58.3%, specificity of 97.77% and positive predictive value of 63.76% in differentiation of persons with significant coronary artery disease from their counterparts.