Plaque regression determined by intravascular ultrasound predicts long-term outcomes of patients with acute coronary syndrome

Aim: the usefulness of drugs to treat plaque regression is assessed by intravascular ultrasound (ivus); however,the impact of plaque regression on clinical outcomes in patients with acute coronary syndrome (acs) has not been established; therefore,we investigated the relationship between coronary plaque regression and long-term clinical outcomes. methods: we analyzed data from 86 patients who underwent percutaneous coronary intervention (pci) and who were assessed in detail at baseline and at 6 months of follow-up by measuring proximal non-culprit sites of pci lesions using volumetric ivus. patients were divided according to changes in plaque volume over 6 months into one group with plaque regression (n = 55; 64.0%) and another with progression (n = 31; 36.0%). they were followed up observationally for a mean of 1,736 days. results: baseline characteristics at the time of acs were similar between the groups. the probability of event-free survival was significantly higher in the regression group than in the progression group as estimated by the kaplan-meier method (log-rank test,p = 0.032). furthermore,the cox hazards model revealed the relative contribution of plaque regression as a predictor of cardiovascular events (hazard ratio: 0.26; 95% ci,0.07 to 0.83; p = 0.023). conclusions: plaque regression determined by volumetric ivus over a period of 6 months was associated with a lower rate of cardiovascular events among patients with acs. this study also demonstrated that plaque regression could be a surrogate marker of future cardiovascular events.