Net clinical benefit of prehospital glycoprotein IIb/IIIa inhibitors in patients with ST-elevation myocardial infarction and high risk of bleeding: effect of tirofiban in patients at high risk of bleeding using CRUSADE bleeding score

Abstract

Aims: The aim of this subanalysis was to assess the net clinical effect of prehospital administration of tirofiban in ST-elevation myocardial infarction (STEMI) patients with high risk of bleeding.

Methods: This is a retrospective subanalysis of the On- TIME 2 trial, a multicenter, controlled randomized trial of the effects of high bolus-dose tirofiban given in the ambulance in STEMI patients. Tirofiban was given on top of aspirin, heparin, and clopidogrel. According to CRUSADE, patients with a moderate to very high baseline risk of bleeding were defined as high risk and patients with a very low or low baseline bleeding risk were defined as low risk. Primary endpoint was net adverse clinical events (NACE) at 30 days (defined as the combined incidence of death, recurrent myocardial infarction, urgent target vessel revascularization, stroke, or non-coronary artery bypass graft [CABG]-related major bleeding).

Results: Of 1309 patients, a high bleeding risk was present in 291 patients (22.2%). In these high-risk bleeding patients, tirofiban significantly improved after percutaneous coronary intervention (PCI) ST-segment resolution. Administration of tirofiban in high-risk bleeding patients showed no difference in 30-day major adverse cardiac events (MACE) (9.4% vs 13.0%; P=.330; relative risk [RR], 0.72; 95% confidence interval [CI], 0.37-1.39). However, pretreatment with tirofiban was associated with a nonsignificant increase in non-CABG related bleeding (8.6% vs 3.6%; P=.082; RR, 2.38; 95% CI, 0.90-6.39). The net clinical effect (30-day NACE) of tirofiban in this group was balanced (11.5% vs 15.2%; P=.365; RR, 0.76; 95% CI, 0.41-1.38).

Conclusion: Prehospital use of tirofiban in STEMI patients with high risk of bleeding improves post-PCI ST-segment resolution, but increases nonsignificantly the risk of non-CABG related bleeding. The net result is a balanced effect on 30-day NACE. Additional studies should clarify how use of bleeding risk scores should modify medical (antiplatelet) therapy.