Ability of mechanical reperfusion to salvage myocardium in patients with acute myocardial infarction presenting beyond 12 hours after onset of symptoms

Background: The ability of primary percutaneous coronary intervention (PCI) to salvage myocardium in patients with acute ST-segment elevation myocardial infarction (STEMI) presenting >12 hours after symptom onset is questionable. The aim of this study was to assess the ability of primary PCI to salvage myocardium in patients with STEMI presenting between 12 and 48 hours after the symptom onset. Methods: In the BRAVE-2 trial, 365 patients with acute STEMI presenting between 12 and 48 hours from the symptom onset were randomized to an invasive (PCI) or a conservative treatment strategy. Two-hundred sixty-one patients enrolled in 2 centers had scintigraphy before randomization and 5 to 10 days later and constitute the cohort of the present study. Salvage index (proportion of initial perfusion defect salvaged) was the primary end point of this study. Results: There were 131 patients randomly assigned to the invasive treatment and 130 patients assigned to the conservative treatment. Initial perfusion defect (median [25th-75th percentiles]) did not differ between groups (17.0% [9.0-28.5] vs 16.0% [9.0-37.5] of the left ventricle; P = .99). The final infarct size, measured in the follow-up scintigraphy, was significantly smaller in patients assigned to the invasive treatment than in those assigned to the conservative treatment (8.0% [2.0-16.0] vs 12.0% [3.2-25.0] of the left ventricle; P = .004). Salvage index was 0.44 (0.13-0.80) in the invasive group versus 0.23 (0.0-0.50) in the conservative group (P < .001). Conclusion: Primary PCI leads to significant myocardial salvage in patients with STEMI presenting between 12 and 48 hours after symptom onset.