Contrast-enhanced MR Imaging for Evaluation of Coronary Artery Disease before Elective Repair of Aortic Aneurysm

Abstract

To prospectively evaluate the accuracy of first-pass contrast material-enhanced magnetic resonance (MR) imaging during stress and delayed contrast-enhanced MR imaging in the detection of significant coronary artery disease in patients before elective repair of aortic aneurysm. The study was approved by the institutional ethics committee, and informed consent was obtained from all patients. MR imaging was performed in 49 patients (42 men and seven women; mean age, 72.2 years; age range, 58-85 years) before the elective repair of atherosclerotic aortic aneurysms. Thirty-two patients had an abdominal aneurysm, 12 had a thoracic aneurysm, and five had a thoracoabdominal aneurysm. First-pass contrast-enhanced MR images were obtained with short-axis sections encompassing the entire left ventricular myocardium in the resting state and during pharmacologic stress. Inversion-recovery-prepared delayed contrast-enhanced MR images were obtained with breath holding to evaluate for the presence of infarction. All patients underwent coronary angiography within 2 weeks of MR imaging, and these findings were used as the standard of reference. The diagnostic results of first-pass contrast-enhanced MR imaging, delayed contrast-enhanced MR imaging, and a combination of both MR imaging methods in the detection of significant coronary artery disease were expressed as sensitivity, specificity, and accuracy. Coronary angiography depicted a clinically significant stenosis (>70% luminal diameter narrowing) in the coronary artery in 34 of the 49 patients (69%). First-pass contrast-enhanced MR imaging depicted stress-induced hypoenhancement in 27 of those 34 patients (79%). Delayed myocardial enhancement was observed in 17 of the 34 patients (50%). The overall sensitivity of rest-stress first-pass contrast-enhanced MR imaging and delayed contrast-enhanced MR imaging combined in the prediction of at least one coronary artery with significant stenosis was 88% (30 of 34 patients). The specificity and accuracy of MR imaging were 87% (13 of 15 patients) and 88% (43 of 49 patients), respectively. Contrast-enhanced MR imaging had an accuracy of 88% in the detection of significant coronary artery disease in patients with aortic aneurysm.