Killip class at presentation and immediate versus staged multivessel PCI in patients with STEMI

Patients with ST-segment elevation myocardial infarction (STEMI) and higher Killip class are at an increased risk of death. We sought to assess outcomes of an immediate or staged multivessel percutaneous coronary intervention (PCI) in patients with higher Killip class presenting with STEMI and multivessel coronary artery disease (MVD). We conducted a subgroup analysis of the MULTISTARS AMI trial with stratification of patients according to Killip classes. Outcomes of patients with Killip class I and Killip class ≥ II were compared. The primary end point was a composite of all-cause death, non-fatal myocardial infarction, stroke, unplanned ischemia-driven revascularization, or hospitalization for heart failure at 1 year. The primary end point occurred in 15 (17.9%) patients with Killip class ≥ II and 78 (11.4%) patients with Killip class I (HR, 1.57 [95%CI, 0.92-2.70], p-value = 0.11). Comparing an immediate with a staged multivessel PCI strategy, the immediate strategy reduced the primary endpoint in patients with Killip class I (6.8% vs. 15.8%; HR, 0.40 [95%CI, 0.25-0.65], p-value < 0.01), whereas the difference was not significant in patients with Killip class ≥ II (20.0% vs. 15.4%; HR, 1.37 [95%CI, 0.50-3.78], p-value = 0.55). There was a significant treatment-by-subgroup interaction for the primary endpoint (P interaction = 0.029), with immediate multivessel PCI not showing an advantage in Killip class ≥ II patients. Conclusively, in the MULTISTARS AMI trial, the benefit of immediate multivessel revascularization strategy observed in patients with Killip class I appeared attenuated in those presenting with Killip class ≥ II, suggesting a potential difference in treatment effect that warrants further investigation. (Supported by Boston Scientific; MULTISTARS AMI, NCT03135275).