Objective: Presence of a coronary chronic total occlusion (CTO) is a common consideration in favor of surgical revascularization. However studies have shown that not all patients undergoing coronary bypass grafting (CABG) have a bypass graft placed on the CTO vessel. The aim of this study was to determine the prevalence of CTO among patients referred for CABG and the significance of incomplete CTO revascularization in these patients.
Methods: The study included 405 consecutive patients undergoing CABG during a 2-year period. Clinical, echocardiographic, and angiographic data were collected. Determination of whether or not a CTO was bypassed was made by correlating data from the surgical reports and pre-procedural angiograms. The primary end-point of this study was 5-year all-cause mortality.
Results: Two hundred twenty one CTOs were found in 174 patients: 132 patients (76%) had 1 CTO; 37 (21%) had 2 CTOs; and 5 (3%) had 3 CTOs. Of 221 CTOs, 191 (86%) were bypassed. All LAD CTOs were grafted, however 12% of LCx and 22% 0f RCA CTOs did not receive bypass grafts. Incomplete CTO revascularization was associated with older age, more co-morbidities including stroke, renal impairment, and lower EF. However, incomplete CTO revascularizaion was not associated with increased 5-year mortality.
Conclusions: Coronary CTOs are a common finding in patients referred for bypass surgery. Presence of a CTO is not independently associated with an adverse long-term outcome. While most CTOs are successfully bypassed, failure to revascularize a non-LAD CTO is not associated with adverse long-term outcome.
