Detection of proximal stenosis of left coronary artery by digital transesophageal echocardiography: feasibility, sensitivity, and specificity.
To assess feasibility, sensitivity, and specificity of transesophageal echocardiography (TEE) in visualizing proximal left coronary artery segments (entire left main, proximal left anterior descending, and circumflex) and in identifying proximal coronary stenosis, 160 consecutive patients were studied. Each patient underwent TEE before coronary angiography; the echocardiographic images were digitized and reviewed in a continuous cineloop format. The entire proximal left coronary artery was adequately imaged in 111 patients (70%). A stenosis was considered to be present at TEE if hyperreflecting plaques narrowing the coronary lumen were observed. TEE observed the presence of a stenosis in 6 of 6, 50 of 63, and 13 of 24 patients with stenosis detected at angiography on the left main, left anterior descending, and circumflex, respectively, and 2 of 105, 5 of 48, and 14 of 87 patients without angiographically detectable coronary stenosis in corresponding coronary segments. Thus, sensitivity and specificity of TEE in identifying stenosis of the left main coronary artery, proximal left anterior descending artery, and proximal circumflex artery were 100% and 98%, 79% and 89%, 54% and 84%, respectively. In conclusion, TEE identification of the proximal left coronary artery is feasible in most patients. Accuracy in identifying significant proximal stenosis varies from segment to segment and is higher for the left main coronary artery.