Surgical revascularization of chronic coronary total occlusions - A systematic review and meta-analysis

Chronic coronary total occlusion (CTO) optimal therapeutic management remains a topic of debate despite its association with adverse clinical outcomes. This study aimed to compare clinical outcomes of patients with CTOs treated with coronary artery bypass graft (CABG) versus medical therapy (MT), assessing the effect of CTO revascularization in patients with multivessel disease undergoing CABG.

In July 2023, PubMed, Embase, Cochrane, and Web of Science databases were systematically searched for studies comparing CTOs treated with CABG versus MT. A sub-analysis of CABG patients, comparing complete surgical revascularization, including CTO bypass, to CABG without CTO bypass, was performed. A pooled odds ratio meta-analysis assessed four main outcomes: mortality, myocardial infarction (MI), stroke, and major adverse cardiovascular events (MACE). The primary outcome was all-cause mortality.

Ten observational studies (6458 patients) comparing CABG-CTO with MT-CTO showed lower all-cause mortality in the CABG group (OR 0.31, 95% CI 0.24-0.40, p<0.001, I²=36%). Despite heterogeneity, CABG exhibited reduced CV mortality and MACE (OR 0.37, 95% CI 0.24-0.57, p<0.001, I²=59%; OR 0.37, 95% CI 0.15-0.92, p=0.03, I²=80%, respectively). The MI rate was lower in the CABG group (OR 0.41, 95% CI 0.30-0.56, p<0.001, I²=0%). Comparing bypassed to non-bypassed CTO groups (5 studies, 1949 patients), the bypassed-CTO group had considerably lower MACE (OR 0.49, 95% CI 0.30-0.81, p=0.005, I²=44%).

This study suggests a clinical benefit of bypassing a CTO in multivessel disease patients during CABG, with significantly lower MACE. The improved outcomes of CABG over MT further underscore these findings, warranting careful consideration by the Heart Team during their decision-making process.