Long-term outcomes of bypass grafting versus drug-eluting stenting for left main coronary artery disease: Results from the IRIS-MAIN registry

Abstract

Background There are limited data on comparative outcomes and its determinants following coronary artery bypass graft surgery (CABG) and percutaneous coronary intervention (PCI) with drug-eluting stents (DES) for left main coronary artery disease (LMCAD) in a real-world setting. Methods A total of 3,504 consecutive patients with LMCAD treated with CABG (n = 1,301) or PCI with DES (n = 2,203) from the IRIS-MAIN registry were analyzed. The relative treatment effect of one strategy over another was assessed by propensity-score matching method. The primary outcome was a composite of death, myocardial infarction, or stroke. Results Median follow-up duration was 4.7 years. In the matched cohort, both groups demonstrated a similar risk for the primary outcome (adjusted hazard ratio [HR]: 0.94; 95% CI: 0.77-1.15; P=.54). Compared with CABG, PCI exhibited higher risks of myocardial infarction (HR: 2.11; 95% CI: 1.16-3.83; P=.01) and repeated revascularization (HR: 5.95; 95% CI: 3.94-8.98; P<.001). In the overall population, age, presence of chronic kidney disease, and low ejection fraction (<40%) were key clinical predictors of primary outcome regardless of the treatment strategy. However, factors deemed to be associated with perioperative morbidity were determinants of primary outcome in the CABG group, whereas those generally associated with the severity of atherosclerotic coronary artery disease were strong predictors in the PCI group. Conclusions Among patients with significant LMCAD, the long-term risk of the composite outcome of death, myocardial infarction, or stroke was similar between CABG and PCI. Clinical variables that differentially predict adverse outcomes might be useful in triaging appropriate revascularization strategy