Possible detection of atherosclerotic coronary calcification by two-dimensional echocardiography

Using two-dimensional echocardiography, a technique was developed for digitizing reflected acoustic signals and performing variable signal processing. This resulted in accentuation of differences in focal reflectivity of target tissues and improved ultrasonic tissue characterization. Study of a learning population of 200 patients demonstrated abnormal specular reflections from the proximal left coronary artery in patients with coronary artery disease. A prospective study of 100 patients was then performed to test the reliability of this method in predicting the presence of significant stenosis. Abnormal echocardiograms were a highly sensitive (94%) but less specific (65%) indicator of significant atherosclerosis of the left coronary symstem. One-third of patients had fluoroscopically identifiable coronary calcification, and 95% had abnormal echocardiograms. We postulate that our echocardiographic findings may be secondary to the presence of small amounts of coronary calcification. Echocardiographic tissue differentiation, therefore, may prove to be a noninvasive means of evaluating patients for coronary atherosclerosis.