Objectives: We have performed a retrospective analysis of the data stratified by time to treatment and by enrollment site: percutaneous coronary intervention hospitals (PCIH), nonpercutaneous coronary intervention hospitals (NoPCIH), or in a pre-hospital setting (PreH).
Background: The ASSENT-4 PCI (Assessment of the Safety and Efficacy of a New Treatment Strategy with Percutaneous Coronary Intervention) trial intended to test the hypothesis that in ST-segment elevation myocardial infarction (STEMI) patients an upfront fibrinolytic bolus before PCI ("facilitated PCI") compared with primary PCI would benefit STEMI patients facing a long pre-PCI delay.
Methods: Seven hundred forty-nine patients (45%) presented directly to PCIH, 578 (34%) presented to NoPCIH, and 334 (20%) were randomized and initially treated in the PreH setting.
Results: Patients in the PreH-facilitated group had the shortest delays (pain-to-fibrinolytic treatment 125 min) and the lowest 90-day mortality (3.1%). Among patients randomized to primary PCI, the shortest time from pain to first balloon was similarly in the PreH group (223 min). They had the lowest mortality of the primary PCI patient groups (4.1%). The highest mortality (8.4%) was in patients presenting to a PCIH and assigned to the facilitated strategy. Their pain-to-lysis time was 174 min and pain-to-PCI time 266 min (or 92 min after lysis).
Conclusions: Few patients fit the target population, long delays to PCI for whom facilitated PCI was designed. Patients treated early after pain onset in the PreH setting do well after a facilitated approach. Despite limitations of post hoc subgroup analysis, these observations suggest caution in extrapolating the results of the ASSENT-4 trial to the "real world" where many patients might have potentially short pain-to-fibrinolysis time but are facing a long transport time to primary PCI.