Effect of revascularization on coronary chronic total occlusion in patients undergoing coronary artery bypass grafting

BACKGROUND: Bypass grafting for chronic total occlusions (CTOs) remains surgically challenging and controversial. Therefore, we evaluated the incidence and clinical outcomes of revascularization on CTOs undergoing coronary artery bypass grafting (CABG). METHODS: Among 828 patients who underwent isolated CABG from January 2010 to December 2018, 245 patients (29.6%) diagnosed with at least one CTO were included and retrospectively reviewed. Primary endpoints were 30-day and overall mortality. Secondary endpoint was the composite outcome of major adverse cardiac and cerebrovascular events (MACCE). RESULTS: With a mean follow-up of 56.6±6.5 months in 245 patients with CTOs, 51 patients (20.8%) received incomplete revascularization (ICR) for CTO lesions. Risk factor analysis showed that ICR was associated with increased 30-day [odds ratio 8.62; 95% confidence interval (CI): 1.64–50; P=0.011] and overall mortality (hazard ratio (HR) 2.13; 95% CI: 1.07–4.21; P=0.03). ICR also increased the risk of MACCE (HR 1.98; 95% CI: 1.12–3.54; P=0.01). Freedom from overall mortality was 92.8%, 90.4%, and 86.8% in the complete revascularization group, and 86.3%, 80.0%, and 72.7% in the ICR group, at 1, 3, and 5 years, respectively (P=0.004). CONCLUSIONS: In patients with CTOs undergoing CABG, the rate of ICR was 20.8%, and it significantly increased the risk of mortality and MACCE. Further studies in a large cohort are needed.