ANGIOSCOPIC EVALUATION OF ATHEROSCLEROTIC PLAQUES - VALIDATION BY HISTOMORPHOLOGIC ANALYSIS AND ASSOCIATION WITH STABLE AND UNSTABLE CORONARY SYNDROMES

Objectives. We validated coronary angioscopic observations with histol ogic assessment of material removed by atherectomy. Background. Up to now, angioscopic findings have been primarily descriptive, and the cli nical significance still needs to be substantiated. The proposed Ermen onville classification is relevant but has not yet been validated by h istomorphologic analysis. Methods. We compared angioscopic findings in patients with different coronary syndromes and used atherosclerotic m aterial retrieved by directional coronary atherectomy to validate the angioscopic observations. Coronary angioscopy was performed in 63 pati ents (56 men, 7 women) with stable (26 patients) and unstable angina ( 37 patients) before and after directional coronary atherectomy. The id entity of atherectomized material was confirmed by ex vivo visualizati on with the angioscope and by postatherectomy angioscopy. Angioscopic and histologic findings could be compared in 44 of 63 patients. Result s. Angioscopic findings were grouped into gray-white and yellow lesion s (gray-yellow, deep yellow, yellow-red or yellow-pink). We found that patients with unstable angina had predominantly yellow lesions (89%). In patients with stable angina, gray-white (43%) or yellow (57%) lesi ons were similarly distributed. Ruptured yellow plaques and red or pin k thrombi were identified in 11% of patients with stable angina and 39 % of patients with unstable or early postmyocardial infarction angina. Histologically, gray-white lesions represented fibrous plaque without degeneration in 64% and with degeneration in 36% of patients. Gray-ye llow lesions were associated predominantly with degenerated plaque (64 %) and, to a lesser extent, with fibrous plaque (14%) or atheroma (14% ). Deep yellow and yellow-red lesions represented either atheroma (53% ) or degenerated plaque (42%). Conclusions. Our study establishes a hi stomorphologic basis for classification and interpretation of angiosco pic findings. Yellow plaque color is closely related to degenerated pl aque or atheroma and is associated with unstable coronary syndromes.