Procedural Characteristics and Clinical Outcomes Associated with Chronic Total Occlusion Percutaneous Coronary Intervention in Patients with a History of Prior Coronary Artery Bypass Graft: A Meta-Analysis

Background: Owing to advances in procedural techniques and the training of interventional staff in catheterization labs, recent work has demonstrated the safety of percutaneous coronary intervention (PCI) as a treatment for patients suffering from chronic total occlusion (CTO). However, there has been little research focused on systematic comparisons of PCI outcomes in CTO patients that did or did not exhibit a history of previous coronary artery bypass grafting (CABG). Methods: Electronic databases were systematically searched for all studies comparing CTO-PCI outcomes for patients with and without a history of CABG, with event rates subsequently being compared via random-effects models with forest plots and odds ratios with 95% confidence intervals (CI), owing to the assumption of between-studies heterogeneity. Results: In total, 8 observational studies enrolling 13,509 CTO patients were identified, including 3389 and 10,120 patients with and without a history of prior CABG, respectively. Patients were enrolled in these studies from 1999-2018. Pooled analyses indicated that CABG history was not linked to a lower proportion of radial access 24 (95% CI 0.52-1.03, p = 0.08), and a prior CABG history was linked to a greater contrast volume (95% CI 0.12-0.44, p < 0.001), higher radiation dose (95% CI 0.27-0.40, p < 0.001), longer fluoroscopy time (95% CI 0.42-0.61, p < 0.001), longer procedural time (95% CI 0.38-0.64, p < 0.001), a higher number of implanted stents (95% CI 0.41-0.60, p < 0.001), longer total stent length (95% CI 0.21-0.60, p < 0.001), higher technical failure rates (95% CI 1.46-1.85, p < 0.001), and higher rates of procedural failure (95% CI 1.42-1.79, p < 0.001). The in-hospital mortality (95% CI 1.50-4.03, p < 0.001) and periprocedural mortality (95% CI 1.63-3.73, p < 0.001) of patients with a history of CABG were also higher. While stroke incidence was comparable in both groups (95% CI 0.80-4.47, p = 0.15), periprocedural major adverse cardiovascular and cerebrovascular events (MACCE) rates were significantly higher among patients exhibiting a history of CABG (95% CI 1.66-2.94, p < 0.001). Conclusions: These results suggest that CTO-PCI procedures may be more challenging and associated with lower rates of success in CABG patients relative to procedures performed in patients without any history of CABG. Moreover, in-hospital outcomes including MACCE and mortality were worse for patients that had undergone prior CABG.