Comprehensive In Vivo Coronary Plaque Mapping: A 3-Vessel Optical Coherence Tomography Study

Abstract Background Previous pathology studies demonstrated that thin-cap fibroatheroma (TCFA) is localized in specific segments of the epicardial coronary arteries. A detailed description of in vivo coronary plaques of various phenotypes has not been reported. Objectives We performed a comprehensive analysis on the distribution of coronary plaques with different phenotypes from our 3-vessel optical coherence tomography (OCT) database. Methods OCT images of all 3 coronary arteries in 131 patients were analyzed every 1 mm to assess plaque phenotype and features of vulnerability. In addition, plaques were divided into tertiles according to percent area stenosis (%AS). Results Among 534 plaques identified in 393 coronary arteries, 27.0% were fibrous plaques, 13.3% fibrocalcific plaques, 40.8% thick-cap fibroatheromas, and 18.9% thin-cap fibroatheromas (TCFA). TCFAs showed clustering in the proximal segment, particularly in the left anterior descending (LAD) artery. On the other hand, fibrous plaques were relatively evenly distributed throughout the entire length of the coronary arteries. In patients with acute coronary syndromes (ACS), TCFAs showed stronger proximal clustering in the LAD, two clustering peaks in the right coronary artery, and one clustering peak in the circumflex artery. The pattern of TCFA distribution was less obvious in non-ACS patients. The prevalence of TCFA was higher in the highest %AS tertile, compared to the lowest %AS tertile (30% vs. 9%, p Conclusions The present 3-vessel OCT study demonstrated that TCFAs cluster at specific locations in the epicardial coronary arteries, especially in ACS patients. TCFA was more prevalent in segments with tight stenosis.