Efficacy and Safety of a Routine Early Invasive Strategy in Relation to Time from Symptom Onset to Fibrinolysis (a Subgroup Analysis of TRANSFER-AMI)

The aim of this study was to assess the efficacy and safety of an early invasive strategy post-fibrinolysis in relation to time from symptom onset to fibrinolysis in patients with ST-elevation myocardial infarction (STEMI). The Trial of Routine Angioplasty and Stenting after Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction (TRANSFER-AMI) randomized 1,059 patients receiving fibrinolysis for STEMI to an early invasive strategy versus standard therapy. The primary end point was the composite of death, reinfarction, recurrent ischemia, new or worsening heart failure, or cardiogenic shock at 30 days. In this post hoc subgroup analysis, we examined the effect of an early invasive strategy on efficacy and safety outcomes after stratification by time from symptom onset to fibrinolysis (<2 or ≥2 hours). Of 1,059 patients in TRANSFER-AMI, 557 (53%) received fibrinolysis <2 hours and 502 (47%) ≥2 hours after symptom onset. Compared to patients who received fibrinolysis within 2 hours of symptoms, patients who received fibrinolysis ≥2 hours after symptom onset had higher Global Registry of Acute Coronary Events risk scores (median 127 vs 122, p = 0.004). The effect of an early invasive strategy did not differ between symptom-to-fibrinolysis time strata for the primary efficacy end point (p-heterogeneity = 0.67), 30-day mortality, the composite of death or reinfarction at 30 days, 6 months, or 1 year, or bleeding (all p-heterogeneity >0.40). In conclusion, the efficacy and safety of an early invasive strategy in patients undergoing fibrinolysis for STEMI do not vary in relation to time (<2 or ≥2 hours) from symptom onset to fibrinolysis.