Frequency and location of yellow and disrupted coronary plaques in patients as detected by angioscopy

Abstract

Background: Clarification of frequency and distribution of yellow plaques and disrupted plaques will increase understanding of acute coronary syndrome (ACS) onset. Methods and Results: Consecutive patients with ACS (n=75) or without ACS (n=90) who received coronary angioscopic examination were studied. Distance from ostium to yellow plaques, diameter stenosis and vessel wall irregularity at the site of yellow plaques, their yellow color grade (grade 1-3) and if they had thrombus were analyzed. Yellow plaques with thrombus were regarded as disrupted. Average number of yellow plaques, grade-3 yellow plaques and disrupted yellow plaques per vessel was 4.0, 0.87 and 1.0, respectively. The number of grade-3 yellow plaques and disrupted yellow plaques per vessel were larger in ACS than in non-ACS patients. Yellow plaques were distributed diffusely in the right coronary artery but more in mid-segments in the left anterior descending coronary artery and left circumflex coronary artery. Diameter stenosis in the non-culprit segments was severer at disrupted than at non-disrupted yellow plaques. Vessel wall irregularity was detected more frequently at disrupted than at non-disrupted yellow plaques. Conclusions: Approximately 4 yellow plaques, 1 grade-3 yellow plaque and 1 disrupted yellow plaque were detected per vessel. About 25% of detected yellow plaques were disrupted. More grade-3 yellow plaques and disrupted yellow plaques were detected in ACS than in non-ACS patients. These findings strengthen the association between yellow plaques detected by angioscopy and ACS events.