Multivessel Coronary Artery Bypass Grafting Versus Percutaneous Coronary Intervention in ESRD

Thirty to sixty percent of patients with ESRD on dialysis have coronary heart disease, but the optimal strategy for coronary revascularization is unknown. We used data from the United States Renal Data System to define a cohort of 21,981 patients on maintenance dialysis who received initial coronary revascularization with either coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) between 1997 and 2009 and had at least 6 months of prior Medicare coverage as their primary payer. The primary outcome was death from any cause, and the secondary outcome was a composite of death or myocardial infarction. Overall survival rates were consistently poor during the study period, with unadjusted 5-year survival rates of 22%–25% irrespective of revascularization strategy. Using multivariable-adjusted proportional hazards regression, we found that CABG compared with PCI associated with significantly lower risks for both death (HR=0.87, 95% CI=0.84–0.90) and the composite of death or myocardial infarction (HR=0.88, 95% CI=0.86–0.91). Results were similar in analyses using a propensity score-matched cohort. In the absence of data from randomized trials, these results suggest that CABG may be preferred over PCI for multivessel coronary revascularization in appropriately selected patients on maintenance dialysis.Cardiovascular disease is the leading cause of death in patients with ESRD.¹ Coronary heart disease affects 30%–60% of patients with ESRD, and it usually involves multiple vessels, proximal lesions, heavy calcifications, or diffuse disease.^2–4 Because of the high burden and poor prognosis of coronary disease in this patient population, optimal management of coronary heart disease—particularly the choice of revascularization modality—is a critical clinical issue.Although there have been several randomized trials comparing multivessel coronary artery bypass grafting (CABG) with multivessel percutaneous coronary intervention (PCI),^5,6 none of these trials included patients with ESRD. Evidence from previous observational studies is mixed; some studies indicate a long-term survival benefit associated with CABG versus PCI,^7–10 whereas other studies show no significant differences in survival.^11–15 These discrepant results may have stemmed, at least in part, from the heterogeneity of the studied populations (e.g., inclusion of patients with single- and multivessel coronary disease and small sample sizes from single institutions). Moreover, most of these studies were performed between the 1970s and early 2000s, and therefore, they do not reflect contemporary practice patterns, such as the use of drug-eluting stents.To address these issues, we used data from the US Renal Data System (USRDS), which collects extensive information for over 95% of patients with ESRD in the United States.¹ We examined the comparative effectiveness of CABG versus PCI between 1997 and 2009 in patients with ESRD on maintenance dialysis. We restricted our analysis to patients undergoing multivessel coronary revascularization to minimize indication bias, because they have the most similar likelihood of receiving either CABG or PCI. We hypothesized that an initial strategy of CABG would be associated with lower risks of mortality and cardiovascular morbidity compared with PCI.