Preoperative computed tomography or intraoperative epiaortic ultrasound for the diagnosis of atherosclerosis of the ascending aorta?

Background: Extensive atherosclerotic disease, usually first diagnosed intraoperatively, is the most important risk factor for postoperative stroke after cardiac surgery. The aim of this study was to investigate if preoperative computed tomography (CT) is comparable with intraoperative epiaortic ultrasound to diagnose severe atherosclerosis in the ascending aorta. Methods: The study included 20 consecutive patients who underwent elective coronary artery bypass surgery. Preoperative CT evaluation of the ascending aorta was compared with intraoperative epiaortic ultrasound findings. The ascending aorta was divided into 12 segments per patient, giving 240 segments to compare. Results: Epiaortic ultrasound detected atherosclerosis in 16.7% +/- 2.4% of the segments, a rate significantly higher than with CT (P = .03). There was a low reliability between the 2 methods, indicated by kappa coefficients of 0.45 or lower. Conclusions: The CT method is inferior to epiaortic ultrasound, today's gold standard, in diagnosing the extent and location of atherosclerosis of the ascending aorta. Other methods, possibly magnetic resonance imaging, should be considered.