Aim: Increased coronary plaque burden, which could be involved in the pathogenesis of atherothrombotic events, is difficult to evaluate in the three major coronary arteries. The purpose of this study was to quantify coronary plaque volume using 64-slice computed tomography (CT).
Methods: We measured coronary plaque volume with our new protocol in 23 consecutive patients (48% men; 66 ± 11 years old) who underwent cardiac CT for suspicion of coronary artery disease and had noncalcified plaques. We counted the total pixel volume of noncalcified plaques in the three major coronary arteries.
Results: The coronary plaque volume was 1.29 ± 0.56 cm(3) in the right coronary artery, 1.29 ± 0.42cm(3) in the left main coronary artery and left anterior descending artery, and 0.88 ± 0.32 cm(3) in the left circumflex artery. The total coronary plaque burden (TCPB) was 3.45 ± 1.02 cm(3)/patient and had a positive correlation with waist circumference (r =0.44, p < 0.05) and insulin resistance (r = 0.46, p < 0.05). TCPB was significantly greater in men (3.89 ± 1.07 cm(3) vs. 3.06 ± 0.82 cm(3) in women, p < 0.05), patients with diabetes or impaired glucose tolerance (3.77 ± 0.94 cm(3) vs. 2.86 ± 0.92 cm(3) in non-diabetics, p < 0.05), and patients with metabolic syndrome (3.91 ± 0.95 cm(3) vs. 3.03 ± 0.91 cm(3) in patients without metabolic syndrome, p < 0.05).
Conclusions: Cardiac CT can provide a noninvasive assessment of TCPB, which was significantly associated with metabolic syndrome and its components. Measuring TCPB by CT could be an important strategy for identifying high-risk patients with suspected coronary artery disease.