Percutaneous coronary intervention using drug-eluting stents versus coronary artery bypass grafting for unprotected left main coronary artery stenosis: A Meta-Analysis of Randomized Trials

Background - Current guidelines suggest that coronary artery bypass grafting (CABG) should be the preferred revascularization method for unprotected left main coronary artery stenosis. In light of evidence from recent randomized trials, we assessed whether percutaneous coronary intervention (PCI) using drug-eluting stents is as safe and effective as CABG for the treatment of unprotected left main coronary artery disease. Methods and Results - Digital databases and manual searches were performed for randomized trials comparing PCI and CABG for unprotected left main coronary artery stenosis. Among 3887 potentially relevant studies, 5 met inclusion criteria. The primary safety end point was defined as the composite of all-cause death, myocardial infarction, or stroke. Secondary end points included a clinical effectiveness composite, which was defined as all-cause death, myocardial infarction, stroke, or repeat revascularization. Summary estimates were obtained using random-effects modeling. In total, 4594 patients were included in the analysis. There was no significant difference in the primary safety end point between the revascularization strategies (odds ratio [OR], 0.97; 95% confidence interval [CI], 0.79-1.17; P=0.73). However, when compared with CABG, PCI was less effective (OR, 1.36; 95% CI, 1.18-1.58; P<0.001) because of significantly higher rates of repeat revascularization (OR, 1.85; 95% CI, 1.53-2.23; P<0.001). The incidence of all-cause death (OR, 1.03; 95% CI, 0.78-1.35; P=0.61), myocardial infarction (OR, 1.46; 95% CI, 0.88-2.45; P=0.08), and stroke (OR, 0.88; 95% CI, 0.39-1.97; P=0.53) did not differ between PCI and CABG. Conclusions - PCI using drug-eluting stents and CABG are equally safe methods of revascularization for patients at low surgical risk with significant unprotected left main coronary artery stenosis. However, CABG is associated with significantly lower rates of repeat revascularization.