CT Coronary Angiography can Safely Exclude Significant Coronary Artery Disease in Patients Undergoing Isolated Valve or Ascending Aorta Surgery

Background: In patients undergoing valve or ascending aorta surgery, significant coronary artery disease (CAD) needs to be excluded. CT coronary angiography (CTCA) is potentially the first line investigation in this population instead of invasive coronary angiography (ICA) which has been traditionally performed. Methods: Between 2012 and 2015 patients with low to intermediate risk and without known CAD were referred for CTCA prior to aortic or valve surgery and were evaluated for 1) the presence of significant CAD, 2) radiation exposure, and 3) perioperative complications. Scans were performed on a Siemens Somatom Definition Flash scanner and were double read by a Cardiologist and Radiologist. Results: Ninety-two patients were imaged (52% male), average age 60 ± 15 yr, weight 85 ± 21 kg, 39% Māori or Pacific Islander. Three CTCA were non-diagnostic. Significant CAD was demonstrated in twelve patients, nine of whom proceeded to ICA with one patient found to have only mild disease. The mean estimated effective radiation dose was 5 ± 6 mSv. Sixty-five patients underwent valve or ascending aorta surgery. One patient had a perioperative myocardial infarct but no significant CAD was found on ICA postoperatively. Conclusion: CTCA effectively rules out CAD in patients undergoing valve or aortic surgery but without the potential risks of ICA.