Long-Term Follow-Up of Patients With Previous Coronary Artery Bypass Grafting Undergoing Percutaneous Coronary Intervention for Chronic Total Occlusion

Abstract

Successful revascularization of chronic total occlusions (CTOs) has been associated with clinical benefit. Data on outcomes in patients with previous coronary artery bypass grafting (CABG) undergoing percutaneous coronary intervention (PCI) for CTO, however, are scarce. A total of 2,002 consecutive patients undergoing PCI for CTO from January 2005 to December 2013 were divided into patients with and without previous CABG, and outcomes were retrospectively assessed. The primary outcome measure was all-cause mortality. Median follow-up was 2.6 years (interquartile range 1.1 to 3.1). A total of 292 patients (15%) had previous CABG; they were older and had a greater prevalence of comorbidities. Procedural success was achieved in 75% and 84% of patients in the previous CABG and the non-CABG groups (p <0.001), respectively. All-cause mortality was 16% and 11% in the previous CABG and the non-CABG groups (p= 0.002), and differences were mitigated after adjustment for baseline characteristics (adjusted hazard ratio [HR] 1.22, 95% confidence interval [CI] 0.86 to 1.74, p= 0.27). All-cause death was significantly reduced in patients with procedural success, both in the previous CABG (11% vs 32%, adjusted HR 0.43, 95% CI 0.24 to 0.77, p= 0.005) and the non-CABG groups (10% vs 20%, adjusted HR 0.63, 95% CI 0.45 to 0.86, p= 0.004), with similar mortality benefits associated with successful revascularization in both groups (interaction p= 0.24). In conclusion, the relative survival benefit of successful recanalization of CTO is independent of previous CABG. However, owing to a greater baseline risk, the absolute survival benefit of successful CTO procedures is more pronounced in patients with previous CABG than in non-CABG patients.