812-3 Angiographic Evidence for Frequent “Silent” Plaque Disruption In Patients with Stable Angina

Histopathological studies of human coronary atheroma (post mortem and atherectomy) suggest that acute coronary syndrome (ACS) may be the extreme end of a spectrum of outcomes from intimal plaque disruption and that “silent” plaque disruption is much more common in the population than would be predicted from the incidence of ACS. It is generally held that angiographic complex coronary stenoses represent previous plaque disruption. We therefore assessed the incidence of angiographic complex plaques in 295 consecutive patients (pts) presenting with moderate to severe stable angina for single vessel PTCA. Two groups were compared: pts with a previous episode of ACS and pts without previous ACS.ResultsThere were no clinical or biochemical differences between groups. Complex stenosis severity was (mean ± 1SD) 67±8% in both groups using quantitative coronary angiography.Angiographic morphologyClinical featuresSmoothComplexnpPrevious ACS35 (38%)56 (62%)0.0001No previous ACS151 (74%)53 (26%)ConclusionThere is a relatively high incidence (26%) of angiographically complex plaques in clinically stable patients with no previous clinical evidence of acute coronary syndrome. This indicates that clinically “silent” plaque disruption is common