All-cause mortality and major cardiovascular outcomes comparing percutaneous coronary angioplasty versus coronary artery bypass grafting in the treatment of unprotected left main stenosis: a meta-analysis of short-term and long-term randomised trials

Objective We compared percutaneous coronary intervention (PCI) with coronary artery bypass grafting (CABG) for the treatment of left main coronary artery (LMCA) disease by conducting a systematic review and meta-analysis of randomised controlled trials (RCTs). Methods RCTs of PCI versus CABG in patients with LMCA stenosis were identified from MEDLINE, the Cochrane Library and search of bibliographies to November 2016. Study-specific HRs with 95% CIs were aggregated for all-cause mortality, major adverse cardiac and cerebrovascular events (MACCE), and other cardiovascular events at time points of 30 days, 1 year and 3 years and beyond. Results Six RCTs comprising 4700 patients were included. There were no significant differences in risk of all-cause mortality in pooled analysis of relevant trials at 30 days (0.61, 95% CI 0.27 to 1.36), 1 year (0.66, 95% CI 0.42 to 1.04), and 3 years and beyond (1.04, 95% CI 0.81 to 1.33), comparing PCI with CABG. There was no significant difference in the risk of MACCE at 30 days (0.72, 95% CI 0.51 to 1.03) and 1 year (1.16, 95% CI 0.94 to 1.44); however, PCI was associated with a higher risk of MACCE compared with CABG during longer-term follow-up (1.27, 95% CI 1.12 to 1.44). Composite outcome of death, stroke or myocardial infarction was lower with PCI at 30 days (0.67, 95% CI 0.49 to 0.92). Repeat revascularisation was increased at 1 year and at 3 years and beyond for PCI. Conclusions All-cause mortality rates are not significantly different between PCI and CABG at short-term and long-term follow-up. However, PCI is associated with a reduction in the risk of major cardiovascular outcomes at short-term follow-up in patients with LMCA stenosis; but at long term, MACCE rate is increased for PCI.