Time-to-reperfusion therapy influences outcome of patients with myocardial infarction subjected to facilitated PCI.

Abstract

The purpose of this study was to evaluate the impact of time-to-reperfusion on outcome after facilitated percutaneous coronary intervention (PCI) i.e. PCI following early pharmacological reperfusion therapy in ST-segment elevation myocardial infarction (STEMI). The study population consisted of 262 consecutive patients with STEMI, aged <75 years, without cardiogenic shock, presenting <12 hours of chest pain onset, transferred from community hospitals to a catheterization laboratory with time delay >90 min after pharmacological reperfusion therapy (alteplase i.v. bolus 15 mg followed by an infusion - 35 mg/60 min; abciximab i.v. bolus 0.25 mg/kg followed by a 12-hour infusion - 0.125 microg/kg/min; unfractionated heparin i.v. bolus 40 U/kg [maximum 3000 U]). One hundred seventeen patients (44.7%) received pharmacological reperfusion therapy <3 h after chest pain onset, 101 (38.5%) at 3-6 h and 44 patients (16.8%) >6 h. Patent infarct-related artery rates at initial angiography were similar among the study groups. PCI significantly improved epicardial flow in all three groups. Mortality at 12 months was significantly related to time-to-pharmacological reperfusion (3.4% [<3 h], 4.0% [3-6 h], 13.6% [>6 h], p = 0.027). At 6 months left ventricular ejection fraction was significantly improved in the two groups of patients with time-to-pharmacological reperfusion <6 hours and the time-to-pharmacological reperfusion was the independent predictor of lack of left ventricular ejection fraction recovery. Our study shows that among STEMI patients undergoing facilitated PCI, time-to-pharmacological reperfusion significantly affects left ventricular function recovery and long-term mortality.