Impact of coronary total occlusion on graft failure and outcomes of coronary artery bypass grafting

Abstract

ObjectiveThe study objective was to assess the impact of chronic total occlusion on long-term graft failure and outcomes in patients who underwent coronary artery bypass grafting. MethodsWe conducted an observational study involving a single-center subgroup of the CORONARY trial. At 6 to 9 years after coronary artery bypass grafting, all alive patients were invited for coronary computed tomography angiography and clinical follow-up. We assessed the association between chronic total occlusion graft and failing graft showing Fitzgibbon type B or O. Risk factors associated with chronic total occlusion graft failure were assessed. The impact of chronic total occlusion on clinical outcomes was analyzed, including death, myocardial infarction, and repeated revascularization. ResultsA total of 349 patients undergoing coronary artery bypass grafting were enrolled between May 2007 and October 2011. Of 301 alive patients at follow-up time (median, 6.8 years; interquartile range, 6.0-8.0 years), repeat coronary computed tomography angiography was performed in 206 patients (68.4%) with 723 grafts (154 chronic total occlusion grafts and 569 nonchronic total occlusion grafts). Chronic total occlusion graft was significantly associated with an increased risk of long-term graft failure after adjustment for patient- and graft-level characteristics (adjusted odds ratio, 2.27; 95% confidence interval, 1.42-3.62; P < .001). Arterial graft, side-to-side anastomosis, higher graft flow, and antiplatelet therapy at discharge were associated with chronic total occlusion graft patency. The presence of 1 or more chronic total occlusions was not significantly associated with long-term composite of death, myocardial infarction, or repeat revascularization (adjusted hazard ratio, 0.91; 95% confidence interval, 0.54-1.51; P = .707). ConclusionsChronic total occlusion graft was associated with an increased risk of graft failure. Surgical technique and guideline-directed medical therapy should be noted to improve chronic total occlusion graft patency.