Percutaneous Coronary Intervention Versus Coronary Artery Bypass Grafting in Unprotected Left Main Coronary Artery Stenosis

Background: The present study performed a meta-analysis of randomized and prospective trials to compare the outcomes of percutaneous coronary intervention (PCI) with stents versus coronary artery bypass graft surgery (CABG) for unprotected left main coronary artery (UPLM) stenosis. Methods: The Cochrane Library, PubMed and EMBASE databases were systematically searched until July 2017. The Newcastle-Ottawa scale was used for quality assessment. Results: A total of 19 studies with 16,900 participants were included. Pooled analysis showed no significant differences in all-cause mortality (odds ratio [OR] 0.94; 95% CI 0.74-1.20) and cardiac death (OR 1.04; 95% CI 0.74-1.47). However, subgroup analysis showed that PCI was associated with a low all-cause mortality rate at 30-day follow up (OR 0.48; 95% CI 0.26-0.89). The stroke rate in PCI was lower in short-term follow up (OR 0.45; 95% CI 0.23-0.88) and long-term follow up (OR 0.36; 95% CI 0.27-0.47). On the other hand, PCI was associated with higher risk of myocardial infarction (OR 1.59; 95% CI 1.34-1.88), repeat revascularization (OR 2.47; 95% CI 1.80-3.37) and target vessel revascularization (OR 2.10; 95% CI 1.72-2.57) compared to CABG in the pooled analysis. Conclusions: The current evidence suggests that the risk of stroke was significantly reduced in PCI compared to that in CABG. Therefore, PCI is the preferred treatment for patients with a high risk of stroke. Additionally, in short-term follow up, PCI was reported to be safe and effective for UPLM patients compared to CABG. However, CABG caused fewer complications long term.