Intravascular ultrasound to assess left main stem coronary artery lesion.

A man of 70 underwent coronary arteriography for the assessment of angina. The appearance of the left coronary main stem was slightly abnormal but no definite stenosis could be delineated. Intracoronary ultrasound examination with a 4.8 French intravascular ultrasound probe showed an extensive plaque in the distal left main stem and proximal left anterior descending coronary artery, with a shelf-like projection causing 60% narrowing at one point in the distal left main stem. Since coronary bypass surgery the patient has been free of angina.