Atherosclerosis is a diffuse process and can be evaluated in the distal part of the left anterior descending coronary artery (LAD). We evaluated whether 2-dimensional high-frequency transthoracic echocardiography could detect changes in coronary wall thickness and size associated with coronary risk factors. In all, 312 patients without a history of coronary artery disease and 40 patients with LAD disease proven by coronary angiography underwent transthoracic echocardiography evaluation of the distal LAD using high-frequency transducer. LAD wall thickness, luminal diameter, external diameter, and coronary flow velocity were measured, and these values were compared according to the number of coronary risk factors (hypertension, hypercholesterolemia, diabetes, smoking, and family history). The feasibility of measuring coronary thickness and coronary flow velocity was 86% and 90%, respectively. LAD wall thickness and external diameter significantly increased according to the increase in the number of risk factors. Patients with 3 or more coronary risk factors showed similar LAD wall thickness (0.82 +/- 0.2 vs 0.89 +/- 0.2 mm) and external diameter (3.4 +/- 0.8 vs 3.3 +/- 0.9 mm) compared with those obtained in patients with LAD disease. High-frequency transthoracic echocardiography is feasible to measure coronary artery wall thickness and external diameter in the distal LAD. This approach has a potential for noninvasive evaluation of the arterial remodeling and the changes in these variables after risk factor modification and intensive drug therapy.