Chronic coronary total occlusions: does surgery hold the answer?

Introduction Chronic coronary total occlusions (CTOs) optimal therapeutic management remains a topic of debate despite its association with adverse clinical outcomes. Purpose To compare the clinical outcomes of patients with CTO treated with surgical revascularization versus medical therapy (MT), assessing the effect of CTO revascularization in patients with multivessel disease undergoing coronary artery bypass graft (CABG). Methods In July 2023, PubMed, Embase, Cochrane, and Web of Science databases were systematically searched for observational and interventional studies comparing CTOs treated with CABG versus MT. We then performed a sub-analysis of studies with patients submitted to CABG comparing complete surgical revascularization, including CTO bypass, versus revascularization without CTO bypass. A pooled odds ratio meta-analysis was conducted for four main outcomes: mortality, acute myocardial infarction (AMI), stroke, and major adverse cardiovascular events (MACE). Random-effects meta-analysis was performed with Review Manager 5.4. Results Ten observational studies, including 6,458 patients, compared CABG-CTO with MT-CTO (65.9% MT; 34.1% CABG). Meta-analysis indicated significantly lower all-cause mortality in the CABG group (OR 0.31, 95% CI 0.24-0.40, p<0.001, I2=36%). Despite high 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). Additionally, the AMI rate was lower in the CABG group (OR 0.41, 0.30-0.56, p<0.001, I2=0%). The stroke rate did not differ significantly between the two treatment groups (OR 3.54, 95% CI 0.73-17.17, p=0.12, I2=71%). In the comparative analysis between the bypassed and non-bypassed CTO groups involving five studies (1,949 patients, 73.7% vs 26.3%, respectively), the bypassed-CTO group exhibited a statistically significant lower MACE (OR 0.49, 95% CI 0.30-0.81, p=0.005, I2=44%). All-cause mortality nearly reached statistical significance (OR 0.64, 95% CI 0.40-1.02, p=0.06, I2=57%). No differences were found in AMI (OR 0.86, 95% CI 0.39-1.86, p=0.70, I2=47%) and stroke (OR 0.95, 95% CI 0.53-1.68, p=0.85, I2=0%) between the abovementioned groups. Conclusion Our study suggests a clinical benefit of bypassing a CTO lesion in patients with multivessel disease undergoing CABG, with a significantly lower MACE and a marginally close value observed for all-cause mortality. The improved clinical outcomes of CABG over MT of CTO lesions further underscore the potential advantages of revascularizing a CTO during CABG rather than leaving it untreated, warranting careful consideration by the Heart Team during their decision-making.