Spontaneous Myocardial Infarction After Left Main Revascularization: The EXCEL Trial

In this pre-specified analysis of the EXCEL trial, 1,882 patients with left main disease underwent percutaneous coronary intervention (PCI) (n=952) or coronary artery bypass grafting (CABG) (n=930). At five years, spontaneous myocardial infarction (MI) was more frequent after PCI than CABG (6.8 percent vs 3.4 percent; adjusted hazard ratio [HR] 2.01, 95 percent confidence interval [CI] 1.29–3.15; P=0.002). The most common mechanism overall was plaque rupture or erosion with thrombosis, occurring at similar rates after both strategies. However, the excess risk after PCI was mainly driven by stent-related failure in this analysis, including in-stent restenosis and stent thrombosis, and events in untreated vessels, rather than protection from proximal plaque events by bypass grafting. Spontaneous MI strongly predicted cardiovascular death (adjusted HR 9.39) and all-cause death (adjusted HR 4.77), with greater prognostic impact than procedural MI.