Marked reduction of early stent thrombosis with pre-hospital initiation of high-dose Tirofiban in ST-segment elevation myocardial infarction

Background: No randomized comparisons are yet available evaluating the effect of pre-hospital high dose tirofiban on the incidence of early stent thrombosis after primary percutaneous coronary intervention (PCI). Objectives: The aim of this analysis was to evaluate whether routine pre-hospital administration of high-dose tirofiban in ST-segment elevation myocardial infarction (STEMI) decreases the incidence of early stent thrombosis after primary PCI. Patients/methods: The Ongoing Tirofiban in Myocardial Evaluation (On-TIME) 2 trial was a prospective multicenter study of consecutive STEMI patients referred for primary PCI in which patients were randomized to pre-hospital no high-dose tirofiban/placebo. We examined the incidence of Academic Research Consortium definite and probable early stent thrombosis and determined predictors and outcome of early stent thrombosis. Results: Primary PCI was performed in 1203 out of 1398 patients (86.1%). In 1073 patients (89.2%) a coronary stent was placed. Early stent thrombosis occurred in 39 patients (3.6%). Pre-hospital initiation of high-dose tirofiban significantly reduced early stent thrombosis (2.1% vs. 5.2%, P = 0.006) and was associated with a lower incidence of urgent repeat PCI (1.9% vs. 5.2%, P = 0.005). Early stent thrombosis, as well as pre-hospital initiation of high-dose tirofiban, was independently associated with 30-day mortality. Conclusions: Pre-hospital initiation of high-dose tirofiban reduces the 30-day incidence of stent thrombosis in STEMI patients treated with primary PCI and stenting. Early stent thrombosis and pre-hospital initiation of high-dose tirofiban were independent predictors of 30-day mortality.