Possibilities of electron beam tomography in noninvasive diagnosis of coronary artery disease: A comparison between quantity of coronary calcification and angiographic findings

Abstract

This study evaluated the diagnostic value of electron beam tomography (EBT) for detection of coronary artery disease and compared different quantitative parameters of coronary calcification to angiographic findings. Coronary calcification is a sensitive marker of coronary atherosclerosis and is of value in predicting coronary artery disease. One hundred twenty patients (mean age 55 years) underwent EBT and coronary angiography. Coronary calcification was quantified by calcified area, number, and CT density of calcified lesions and a calcium score defined by the product of calcified area, number, and CT density of calcified lesions. The quantity of calcification was related to the number of coronary vessels with significant stenosis and to the maximal degree of stenosis in angiography. The positive predictive value of EBT was 94%; negative predictive value was higher in older than in younger subjects (56% vs 94%). Quantity of calcification increased corresponding to the extend of coronary artery disease. Mean calcified area increased in significant one-vessel disease (9.3-fold), two-vessel disease (24-fold), and three-vessel disease (34.7-fold) compared with values in subjects without coronary artery disease. Calcified area in women with coronary artery disease was lower than in men, however, this difference decreases with age from 6.3-fold (age < 50 years) to 1.8-fold (age > 60 years). Detection of coronary calcification, helped in this study to distinguish, with high significance, between the presence or absence of coronary artery disease. The quantity of coronary calcium increased with the angiographic degree of coronary artery disease but due to the variation of calcification within a disease category the differentiation between disease category was not absolutely certain.