Intracoronary nitroprusside for the prevention of the no-reflow phenomenon after primary percutaneous coronary intervention in acute myocardial infarction. A randomized, double-blind, placebo-controlled clinical trial

BACKGROUND: The aim of this study was to test whether nitroprusside (NTP) injected intracoronary immediately before primary angioplasty for acute ST-elevation acute myocardial infarction (STEMI) prevents no-reflow and improves vessel flow and myocardial perfusion. METHODS: Ninety-eight patients presenting with STEMI were evenly randomized to receive either NTP (60 microg) or placebo. The drug was selectively injected into the infarct-related artery, distal to the occlusion, in a double-blind manner. The primary end points were postintervention angiographic corrected thrombolysis in myocardial infarction frame count and the proportion of patients with complete (>70%) ST-segment elevation resolution. Secondary end points included myocardial blush score and clinical outcome at 6 months follow-up. RESULTS: Mean (+/-SD) age was 62 (+/-12) years, and 87% were men. Baseline characteristics (excluding sex) did not differ between groups. The corrected thrombolysis in myocardial infarction frame count after angioplasty was 20.8 (+/-18.6) and 20.3 (+/-21.3) in patients given NTP and placebo, respectively (P = .78). Complete ST-segment resolution was achieved in 61.7% and 61.2% of NTP and placebo subjects, respectively (P = .96). The distribution of myocardial blush score did not differ between groups. At 6 months, the rate of target lesion revascularization, myocardial infarction, or death occurred in 6.3% of the NTP group and 20.0% of the placebo group (P = .05). CONCLUSIONS: In patients with STEMI, selective intracoronary administration of a fixed dose of NTP failed to improve coronary flow and myocardial tissue reperfusion but improved clinical outcomes at 6 months.