Drug-eluting stents or coronary artery bypass grafting for unprotected left main coronary artery disease: a meta-analysis of four randomized trials and seventeen observational studies

BACKGROUND: The clinical application of drug-eluting stents (DES) or coronary artery bypass grafting (CABG) for unprotected left main coronary artery disease (ULMCAD) is still controversial. The purpose of this meta-analysis was to compare the safety and efficacy between DES and CABG for ULMCAD. METHODS: Databases of MEDLINE, EMBASE and the Cochrane Library were systematically searched. RESULTS: Twenty-one studies with 8,413 patients were included in this meta-analysis. The risk was lower in DES than in CABG groups at the early outcomes of death (risk ratio (RR): 0.49, 95% confidence interval (CI): 0.30–0.78), cerebrovascular events (RR: 0.19, 95% CI: 0.08–0.45) and composite endpoint (RR: 0.53, 95% CI: 0.40–0.70); death after 2 years (RR: 0.81, 95% CI: 0.66–0.99), 4 years (RR: 0.69, 95% CI: 0.53–0.90), 5 years (OR: 0.76, 95% CI: 0.61–0.95) and their total effect (RR: 0.79, 95% CI: 0.71–0.87); composite endpoint 1 year (RR: 0.69, 95% CI: 0.58–0.83), 4 years (RR: 0.69, 95% CI: 0.53–0.88), 5 years (RR: 0.74, 95% CI: 0.59–0.92) and their total effect (RR: 0.78, 95% CI: 0.71–0.85). There were no significant differences in the risk for the early outcomes of myocardial infarction (RR: 0.97, 95% CI: 0.68–1.38), death 1 year (OR: 0.81, 95% CI: 0.57–1.15) and 3 years (OR: 0.85, 95% CI: 0.69–1.04), composite endpoint of 2 years (RR: 0.88, 95% CI: 0.72–1.09) and 3 years (RR: 0.87, 95% CI: 0.73–1.04). Nonetheless, there was a lower risk for revascularization associated with CABG from 1 to 5 years and their total effect (RR: 3.77, 95% CI: 3.35–4.26). There was no difference in death, myocardial infarction, cerebrovascular events or revascularization at 1 year between RCT and observational groups. CONCLUSIONS: Our meta-analysis indicates that DES has higher safety but higher revascularization than CABG in patients with ULMCAD in the 5 years after intervention.