CORONARY-ARTERY PLAQUE MORPHOLOGY IN STABLE ANGINA AND SUBSETS OF UNSTABLE ANGINA - AN IN-VIVO INTRACORONARY ULTRASOUND STUDY

Little information is available regarding the in vivo composition of a ngina producing culprit atherosclerotic lesions in various anginal syn dromes. In this study we used intracoronary ultrasound to determine th e composition of culprit lesions in various subsets of anginal syndrom es and correlated this composition with the patient's clinical present ation. One hundred and forty six patients referred for angioplasty or atherectomy were classified as having either chronic stable angina (an gina which was clinically unchanged for > 2 months), crescendo angina (an accelerating pattern of frequent or prolonged anginal episodes), s evere rest angina (abrupt onset of prolonged angina) or post-infarctio n angina (angina within 2 weeks of acute myocardial infarction). Intra coronary ultrasound imaging of the culprit lesion was performed before intervention. Lesions were classified as soft, mixed fibrous without calcium, mixed fibrous with calcium or calcified. Analysis of the ultr asound images revealed that the majority of culprit lesions were soft in severe rest (71%) and post-infarction angina (73%) whereas, the maj ority of culprit lesions were mixed fibrous or calcified in chronic st able (69%) and crescendo (53%) angina (X(2) = 22.73, p = 0.007). In ad dition, the frequency of intralesional calcium in chronic stable or cr escendo angina was significantly higher than that in severe rest or st able angina. We conclude that the composition of culprit lesions in va rious anginal subsets are different. The lesion morphology in crescend o angina frequently resembles that in chronic stable angina; while tho se in severe rest and post-infarction angina are frequently similar. T hese findings may have implications for medical or interventional trea tment of patients with angina.