Background Chronic total occlusions (CTOs) of native coronary arteries are a frequent finding among patients who are referred for surgical revascularization with coronary artery bypass grafting (CABG). The long-term clinical significance of native coronary artery CTO identified at baseline and 1 year after CABG is unknown. Methods All patients who underwent 1-year follow-up angiography as part of the multicentre Radial Artery Patency Study (RAPS) were assessed for late clinical events. Results At a mean follow-up of 7.3 ± 2.9 years, the study group of 388 patients had the following outcomes: 39 (10%) deaths, 6 (1.5%) cases of nonfatal myocardial infarction, and 19 (4.9%) cases of percutaneous coronary intervention (PCI). CTO of ≥ 1 native coronary artery in the baseline preoperative coronary angiogram was demonstrated in 240 (61.9%) patients. The composite of all-cause death, nonfatal myocardial infarction, and PCI occurred significantly more often in patients with at least 1 preoperative CTO than in patients without a preoperative CTO (20% vs 11%; P = 0.048). A new native coronary artery CTO 1 year after surgery occurred in 169 (43.6%) patients. The composite of all-cause death, nonfatal myocardial infarction, and PCI occurred significantly more often in patients with a new CTO 1 year after CABG compared with those without a new CTO (21.3% vs 12.8%; P = 0.028). Conclusions In patients undergoing CABG, both preoperative CTOs and new CTOs that develop 1 year after surgery are associated with adverse long-term clinical outcomes.