One-Year Survival After ST-Segment–Elevation Myocardial Infarction in Relation With Prehospital Administration of Dual Antiplatelet Therapy

Abstract

Background The optimal timing of administration of dual antiplatelet therapy (DAPT) in acute ST-segment–elevation myocardial infarction patients is debated. Clinical trials have failed to demonstrate the superiority of pretreatment with P2Y12 inhibitors in ST-segment–elevation myocardial infarction, but they were not designed to assess hard clinical end points. We used data from the FAST-MI (French Registry on Acute ST-Segment–Elevation or Non-ST-Segment–Elevation Myocardial Infarction) cohorts to determine 1-year survival and in-hospital outcomes in patients receiving DAPT, comparing prehospital versus in-hospital administration. Methods and Results The FAST-MI program collects extensive data on patients admitted in France for acute myocardial infarction over a 1-month period every 5 years since 2005. For the present analysis, 3548 patients with ST-segment–elevation myocardial infarction ≤12 hours from symptom onset, transported by physician-staffed emergency medical system ambulances, not treated with intravenous fibrinolysis, and receiving DAPT were included, of whom 44% received DAPT in the ambulance. The primary end point was 1-year survival as assessed by multivariate Cox analysis and propensity score analysis. In-hospital bleeding and ischemic complications were also analyzed. Adjusted in-hospital mortality was numerically but not significantly lower in patients with prehospital DAPT. There were no differences in in-hospital bleeding complications. Fully-adjusted hazard ratio for 1-year death in patients with prehospital versus in-hospital DAPT was 0.69 (95% CI, 0.51–0.92; P =0.011), and propensity score–adjusted hazard ratio was 0.55 (95% CI, 0.41–0.73; P =0.001) in the whole population. In the propensity score–matched cohorts (360 patients each), 1-year survival was 93.9% in patients with prehospital versus 90.3% in those with in-hospital DAPT (hazard ratio, 0.62; 95% CI, 0.36–1.05; P =0.077). Results were consistent in subgroups, including by year of survey, age, presence of out-of-hospital cardiac arrest, morphine use, and type of P2Y12 inhibitor used. Conclusions In these cohorts of ST-segment–elevation myocardial infarction patients considered for primary percutaneous coronary intervention, prehospital administration of DAPT was associated with higher 1-year survival and no increase in in-hospital bleeding complications. The magnitude of the decrease in 1-year mortality, however, may suggest the persistence of some degree of residual confounding. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifiers: NCT00673036, NCT01237418, and NCT02566200.