Development of De Novo Chronic Total Occlusion in Native Coronary Arteries of Coronary Artery Bypass Grafting Surgery Patients

Aim: Postoperative de novo chronic total occlusions (CTOs) of preoperatively non-occluded native coronary arteries are commonly seen in coronary artery bypass grafting (CABG) surgery patients in the clinical follow-up; however, data about this course is limited. The aim of this study was to investigate the prevalence of new CTO development in native coronary arteries postoperatively and the clinical factors which may play role in this context. Methods: A total of 492 CABG patients has been searched from the computer database at Başkent University Hospital Alanya Application and Research Center and patients with a recurrent coronary angiography (CAG) procedure after the first 6 months following surgery were involved in the study population. Recurrent CAG recordings were evaluated for the presence of new CTO development. Logistic regression analysis was used to search the role of demographical and angiographical characteristics in the development of de novo CTOs in native coronary arteries. Results: Seventy-three CABG patients with recurrent CAG were involved in statistical analysis (Mean age was 65.2 ± 9.8 years; male gender 76.7%). Two hundred eighteen preoperatively non-occluded native coronary arteries were evaluated and 119 new CTOs were detected (54.5% of involved vessels). Preoperative proximal stenosis ≥90% is related to more than 3 times new CTO development (67.8% vs. 22.2%) (p<0.001). Dual antiplatelet therapy (DAPT) is found as a protective factor for the patency of native coronary arteries (HR:-0.259; 95% CI:-0.475 to -0.017; p=0.036). Conclusion: De novo CTO development in native coronary arteries is commonly seen in CABG patients postoperatively. Significance of preoperative stenosis and absence of DAPT seem to be the essential factors in new CTO occurrence.