The effect of low-dose thrombolysis followed by back-up tracoronary stent implanting for acute myocardial infarction

Objective The aim of this study was to elucidate the efficacy and safety of the injection of a low-dose recombinant tissue-type plasminogen activator(rt-PA), followed by back-up in tracoronary stent implanting in patients with acute myocardial infarction(AMI). Methods The 112 patients with AMI who were admitted to hospital within 6 hours of onset of symptoms were randomiy assigned to a treatment with 50 mg bolus rt-PA group(group T, n=56) and no rt-PA group (group P,n=56), followed by back-up intracoronary stent implanting. The results of angiography, success rate of intracoronary stent implanting, left ventricular end-diastolic volume and left ventricular ejection were compared in two groups. Results The coronary angiographies showed that the blood flow of coronary reaching TIMI gradeⅡand grade Ⅲ was significantly higher in group T than in group P( 67.8% vs 16.1%, P0.05=. The success rate of intracoronary stent implanting was 100% in group T, while 96.9% in group P. The left ventricular ejection after 3 months was significantly higher in group T than in group P[(59.2±11.2)% vs (50.6±10.9)%, P0.05=. The bleeding comlications were of no significant vaviation. Conclusion These findings explain the treatment with 50 mg bolus rt-PA followed by back-up in tracoronary stent implanting is effective for the early reperfusion and preservation of left ventricular function, without increasing of bleeding complications in patients with AMI.