Association between advanced Killip class at presentation and impaired myocardial perfusion among patients with ST-segment elevation myocardial infarction treated with primary angioplasty and adjunctive glycoprotein IIb-IIIa inhibitors

Abstract

Although primary angioplasty has been shown to improve survival as compared with thrombolysis, the outcome is still unsatisfactory in subsets of patients such as those with signs of heart failure at presentation. In fact, although primary angioplasty is able to restore TIMI 3 flow in most patients, suboptimal myocardial reperfusion is observed in a relatively large proportion of patients. The aim of this study was to investigate among patients with ST-segment elevation myocardial infarction undergoing primary angioplasty the association between heart failure at presentation and myocardial perfusion and its implications in terms of survival. Our population is represented by patients undergoing primary angioplasty who are included in the EGYPT database. Congestive heart failure was defined as Killip class >1 at admission. Myocardial perfusion was evaluated by myocardial blush grade and ST-segment resolution. Follow-up data were collected between 30 days and 1 year after primary angioplasty. Detailed data on Killip class at presentation were available in 1,427 of 1,662 patients (86% of the initial population) who represent the final population of this study. Killip class was associated with myocardial perfusion, distal embolization, enzymatic infarct size, predischarge ejection fraction, and 1-year mortality rate. Myocardial blush was an independent predictor of 1-year mortality (hazard ratio 7.44, 95% CI 1.82-30.4, P = .005) in patients with advanced Killip class at presentation. Our study shows that patients with heart failure complicating ST-segment elevation myocardial infarction have impaired myocardial perfusion, which accounts for the poor outcome observed in these patients. Further efforts should be aimed at improving myocardial perfusion, beyond epicardial recanalization, to further improve the outcome of these high-risk patients.