Coronary computed tomography as an alternative to invasive coronary angiography in the evaluation of patients referred for valvular disease surgery

Abstract

Background: Coronary angiography is routinely performed in most patients referred for valvular or thoracic aortic disease surgery. Coronary computed tomography (CT) angiography is currently the only alternative to invasive angiography in the evaluation of coronary anatomy. Aim: An assessment of the usefulness of dual-source CT for the evaluation of coronary anatomy in patients before planned cardiac valvular surgery. Methods: 98 consecutive patients with a haemodynamically significant valvular heart disease and guideline based indications for coronary angiography to exclude CAD before planned valvular surgery were included. Exclusion criteria were: cardiac arrhythmia (atrial fibrillation, frequent ventricular and supraventricular premature beats), estimated glomerular filtration rate 1000. In the remaining patients, complete CT evaluation was performed with the administration of a contrast agent. Conventional invasive coronary angiography was subsequently performed in patients with at least one > 50% stenosis, artifacts due to calcifications, or motion artifacts. Results: In 79 (80.6%) patients, CT angiography excluded the presence of a significant coronary artery stenosis without the need for invasive angiography. Conventional coronary angiography was required in 19 (19.4%) patients, including 13 (13.3%) patients with a > 50% stenosis in CT angiography, 2 (2%) patients with calcification artifacts, 1 (1%) patient with motion artifacts, 2 (2%) patients with CACS > 1000 in whom CT angiography was nor performed, and 1 (1%) patient with allergic symptoms during administration of a test dose of the contrast agent. Ultimately, significant CAD was diagnosed in 9 (9.2%) patients in whom coronary artery bypass surgery was also performed. In addition, cardiac CT angiography revealed vascular anomalies in 5 (5.1%) patients. In 14 patients, CT angiography was also used for previously planned evaluation of a coexisting aortic aneurysm. Conclusions: Coronary CT angiography may be useful to exclude significant CAD in patients referred for valvular disease surgery. It also allows concomitant evaluation of other cardiac structures, large vessels including the thoracic aorta, and calcifications within the aorta, aortic valve and mitral apparatus.