Coronary atherosclerosis is a pathologic process that produces thickening of the wall of the coronary arteries. but coronary angiography does not examine the wall but only the lumen of the vessels. IVUS has confirmed autopsy data that coronary atheroslerosis is diffuse and almost always involve the proximal portion of coronary arteries. We assess the meaning of the high echogenicity with thickening (HET) on transthoracic coronary echogram of proximal coronary arteries and to evaluate whether HET predicts the severity of coronary artery disease on coronary angiogram.

112 patients (M:F=73:39, mean age=57±12 years) referred for coronary angiography were included in this study. We detected proximal coronary artery using transthoracic echocardiogram (3.5 MHz transducer, H-P Sonos 5500). We defined that high echogenicity with thickening (HET) is more than 1.5 mm in thickness with high echogenicity and persistence. Coronary angiography were performed in all patients. Of these patients, 29 vessels were examined by IVUS (Intravascular Ultrasound, 30 MHz) and 122 vessels by Fluoroscopy.

1) HET on coronary echogram had sensitivity of 80% and 88% and specificity of 79% and 82% for identifying calcification on IVUS and fluoroscopy, respectively. 2) HET on coronary echogram had sensitivity of 74% and specificity of 86% for identifying the significant stenosis of proximal left coronary artery. 3) HET on coronary echogram was observed more frequently in 3 vessel diseases compared to normal coronary arteries and 1 or 2 vessel diseases (p<0.05, respectively). 4) HET on coronary echogram was observed in vessels with more complex lesions.

High echogenicity with thickening on coronary echogram may be related to the presence of calcification and predict far advanced coronary atherosclerosis. Technique using echocardiographic tissue characterization of proximal coronary arteries may become a sensitive means of screening for coronary atherosclerosis in asymptomatic patients.