Impact of Coronary Collaterals on Long-term Prognosis in Patients Treated With Primary Angioplasty.

INTRODUCTION AND OBJECTIVES: The beneficial effect of coronary collateral circulation (CC) in patients with ST-segment elevation myocardial infarction is controversial. The aim of this study was to evaluate the impact of CC before reperfusion with primary angioplasty (PA) on the long-term prognosis of these patients. METHODS: Retrospective observational study of a cohort of 947 patients treated with PA and TIMI grade ≤ 1 flow in a single center from 2005 to 2013. Propensity score matching was used to create 2 groups of 175 patients each, matched by the degree of CC (Rentrop 0-1 vs Rentrop 2-3). In the matched cohort, we determined the impact of CC on total mortality, cardiovascular mortality, and a combined adverse cardiovascular event endpoint for a median follow-up of 864 (interquartile range, 396-1271) days. RESULTS: Of a total of 947 patients included, 735 (78%) had Rentrop 0 to 1 and 212 (22%) had Rentrop 2 to 3. During follow-up, 105 patients died, 71 from cardiovascular causes. In the matched cohort, the total mortality rate was similar between the 2 groups (Rentrop 0-1 [8.8%] vs Rentrop 2-3 [6.3%]; HR = 1.22; 95%CI, 0.50-2.94; P = .654). There were no differences in cardiovascular mortality (Rentrop 0-1 [4.6%] vs Rentrop 2-3 [2.3%]; sHR = 0.49; 95%CI, 0.14-1.62; P = .244) or the composite endpoint including cardiovascular death, reinfarction, target vessel revascularization, and coronary artery bypass surgery (Rentrop 0-1 [18.8%] vs Rentrop 2-3 [13.1%]; sHR = 0.68; 95%CI, 0.40-1.15; P = .157). CONCLUSIONS: In this contemporary series, the presence of good CC before PA was not associated with better long-term clinical outcomes.