Coronary Artery Bypass Grafting vs Percutaneous Coronary Intervention and Long-term Mortality and Morbidity in Multivessel Disease

Abstract

Recent trials of percutaneous coronary intervention (PCI) vs coronary artery bypass grafting (CABG) for multivessel disease were not designed to detect a difference in mortality and therefore were underpowered for this outcome. Consequently, the comparative effects of these 2 revascularization methods on long-term mortality are still unclear. In the absence of solid evidence for mortality difference, PCI is oftentimes preferred over CABG in these patients, given its less invasive nature. To determine the comparative effects of CABG vs PCI on long-term mortality and morbidity by performing a meta-analysis of all randomized clinical trials of the current era that compared the 2 treatment techniques in patients with multivessel disease. A systematic literature search was conducted for all randomized clinical trials directly comparing CABG with PCI. To reflect current practice, we included randomized trials with 1 or more arterial grafts used in at least 90%, and 1 or more stents used in at least 70% of the cases that reported outcomes in patients with multivessel disease. Numbers of events at the longest possible follow-up and sample sizes were extracted. A total of 6 randomized trials enrolling a total of 6055 patients were included, with a weighted average follow-up of 4.1 years. There was a significant reduction in total mortality with CABG compared with PCI (I2 = 0%; risk ratio [RR], 0.73 [95% CI, 0.62-0.86]) (P < .001). There were also significant reductions in myocardial infarction (I2 = 8.02%; RR, 0.58 [95% CI, 0.48-0.72]) (P < .001) and repeat revascularization (I2 = 75.6%; RR, 0.29 [95% CI, 0.21-0.41]) (P < .001) with CABG. There was a trend toward excess strokes with CABG (I2 = 24.9%; RR, 1.36 [95% CI, 0.99-1.86]), but this was not statistically significant (P = .06). For reduction in total mortality, there was no heterogeneity between trials that were limited to and not limited to patients with diabetes or whether stents were drug eluting or not. Owing to lack of individual patient-level data, additional subgroup analyses could not be performed. In patients with multivessel coronary disease, compared with PCI, CABG leads to an unequivocal reduction in long-term mortality and myocardial infarctions and to reductions in repeat revascularizations, regardless of whether patients are diabetic or not. These findings have implications for management of such patients.