For patients with multivessel disease, which is the better approach for reducing long-term mortality: coronary artery bypass grafting or percutaneous coronary intervention?
When compared with percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG) reduces overall mortality and myocardial infarctions (MIs) in patients with multivessel disease. You would need to treat 37 patients with CABG to prevent one death, and 26 patients with CABG to prevent one MI over an average follow-up of 4 years. This is compared with a number needed to treat to harm of 105 to cause one additional stroke with CABG. (LOE = 1a)
Sipahi I, Akay H, Dagdelen S, Blitz A, Alhan C. Coronary artery bypass grafting vs percutaneous coronary intervention and long-term mortality and morbidity in multivessel disease: meta-analysis of randomized clinical trials of the arterial grafting and stenting era. JAMA Intern Med 2014;174(2):223-230.
Meta-analysis (randomized controlled trials)
Existing trials that compare CABG with PCI are underpowered to detect a difference in long-term mortality or MI. To study these outcomes, these investigators searched multiple databases, including MEDLINE and the Cochrane Central Register of Controlled Trials, to find randomized controlled trials that compared the 2 approaches over an average follow-up of at least 1 year in patients with multivessel disease. To ensure that these trials reflected contemporary practice, the authors only included trials in which arterial grafts were used in 90% of the CABG cases and trials in which stents were used in 70% of the PCI cases. Two investigators independently extracted data from the 6 included trials. No formal quality assessment was performed. No publication bias was detected. When taken together, data from the 6 trials (N = 6055) showed that the use of CABG as compared with PCI resulted in a 27% reduction in mortality (relative risk [RR] = 0.73; 95% CI, 0.62-0.86) and a 42% reduction in MI (RR = 0.58; 0.48-0.72). Although there was a nonsignificant trend toward increased strokes in the CABG group (likely related to periprocedural events), this approach also led to fewer repeat revascularizations (number needed to treat [NNT] = 7), as well as fewer overall major adverse cardiac and cerebrovascular events (NNT = 10).
Dr. Kulkarni is an assistant professor of hospital medicine at Northwestern University in Chicago.