Background: Chronic total occlusions (CTOs) of native coronary arteries are a frequent finding among patients who are being referred for surgical revascularization with coronary artery bypass grafting (CABG). The long term clinical significance of native coronary artery CTO identified at baseline and at 1 year post CABG is unknown.
Methods: All patients who underwent 1-year follow-up angiography as part of the multi-centre Radial Artery Patency Study (RAPS) were followed up for late clinical events.
Results: The study included 388 patients, with median follow up of 7.3±2.9 years had the following outcomes:39 (10%) deaths, 6 (1.5%) with non-fatal myocardial infarction and 19 (4.9%) underwent PCI. CTO of ≥1 native coronary artery in the baseline pre-operative coronary angiogram was demonstrated in 240 (61.9%) patients. The composite of all-cause death, non-fatal myocardial infarction and PCI, occurred significantly more often in patients with at least one pre-operative CTO than in patients without a pre-operative CTO (20% vs 11% respectively, p=0.048). A new native coronary artery CTO at 1 year post surgery occurred in 169 (43.6%) patients. The composite of all-cause death, non-fatal myocardial infarction and PCI, occurred significantly more often in patients with a new CTO at 1 year post CABG compared to those who did not (21.3% and 12.8%, respectively, p=0.028)
Conclusion: Among patients undergoing CABG, both pre-operative CTOs and new CTOs that develop 1 year following surgery are associated with adverse long term clinical outcomes.
