A systematic review including 5 RCTs with a total of 2 943 subjects was abstracted in DARE. Fifty-seven per cent of the patients had 2-vessel disease, 28% had 3-vessel disease, and 15% had 1-vessel disease. Results at 1–3 years of follow-up: Overall risk of death was similar in CABG (3.7%) and in PTCA (3.9%), OR 0.93. Combined risk of death or nonfatal myocardial infarction was also similar in CABG patients (10.1%) and in PTCA patients (9.8%), OR 1.03. CABG patients were significantly more likely to be angina-free (80.7% vs 73.1%), OR 1.57 (95% CI 1.32 to 1.87) and less likely to undergo either a new CABG (1% vs 19.7%) or PTCA (6% vs 22.9%).
A Cochrane review (abstract , review ) included nine studies with a total of 3519 subjects. Four RCTs included patients with multiple vessel disease, five focused on single vessel disease. Four studies reported beyond 1 year. No statistical differences were observed between CABG and stenting for meta-analysis of mortality or AMI, but there was heterogeneity. Composite cardiac event and revascularisation rates were lower for CABG than for stents. Odds ratios resulting from meta-analysis of event rate data at 1 year were, odds ratio 0.43 (95% CI 0.35 to 0.54) and at 3 years, odds ratio 0.37 (95% CI 0.29 to 0.48). Odds ratios for revascularisation at 1 year were, odds ratio 0.18 (95% CI 0.13 to 0.25) and at 3 years, odds ratio 0.09 (95% CI 0.02 to 0.34). Binary restenosis at 6 months (single vessel trials) favoured CABG, odds ratio 0.29 (95% CI 0.17 to 0.51).
Comment: The quality of evidence is downgraded by study limitations and indirectness (RCT data are limited by follow-up, unrepresentative samples and rapid development of both surgical techniques and stenting).