Usefulness of thoraco-abdominal computed tomography angiography in coronary artery bypass patients

Computed tomography (CT) angiography has been widely used for evaluating cardiovascular structures in cardiac surgical patients. The aims of this study were to assess the prevalence of incidental findings (IF) from preoperative thoraco-abdominal multidetector CT (MDCT) angiography, to evaluate their clinical significance, and to elucidate predisposing factors for IF in patients undergoing coronary artery bypass grafting (CABG). Of the 456 patients who underwent isolated CABG between 2014 and 2016, 443 patients (97.1%) underwent preoperative thoraco-abdominal MDCT angiography. The medical records of patients were retrospectively reviewed, and all significant IFs that influenced perioperative management and required additional intervention or follow-up were analysed. Two hundred and ninety-two IFs having clinical significance and affecting perioperative management were observed in 208 patients (47.0%); 231 atherosclerotic IFs in 176 patients and other 61 miscellaneous IFs in 61 patients. Twenty-nine patients had both atherosclerotic and miscellaneous IFs with significance. A multivariable analysis demonstrated that advanced age, chronic renal failure, recent acute myocardial infarction, and left ventricular dysfunction were predisposing factors for IFs with significance. An additional usefulness of MDCT angiography was evaluation of the internal thoracic artery and the iliofemoral artery in patients whose internal thoracic artery was not evaluated during coronary angiography (n = 119; 26.9%) and who received perioperative peripheral mechanical circulatory support (n = 33; 7.4%), respectively. Considering the high prevalence of IFs with significance in approximately half of the patients and the additional usefulness in one-third of the patients who underwent CABG, we recommend thoraco-abdominal MDCT angiography for preoperative evaluation, especially in elderly patients and those who have chronic renal failure or left ventricular dysfunction.