High-dose dobutamine-atropine stress cardiovascular MR imaging after coronary revascularization in patients with wall motion abnormalities at rest.

PURPOSE: To determine the value of high-dose dobutamine-atropine stress cardiovascular magnetic resonance (MR) imaging for diagnosis of ischemia in patients with coronary artery disease (CAD) who had undergone revascularization and have wall motion abnormalities at rest, with quantitative invasive coronary angiography serving as reference standard.

MATERIALS AND METHODS: One hundred sixty consecutive patients (mean age, 59 years +/- 8 [standard deviation]) who had undergone revascularization for CAD and have wall motion abnormalities at rest underwent stress cardiovascular MR imaging prior to clinically indicated invasive coronary angiography. Turbo gradient-echo MR images were acquired at rest and during a standardized high-dose dobutamine-atropine protocol with three short-axis and two long-axis views. Regional wall motion was assessed by a blinded observer by using a 16-segment model and a four-point scoring system. New or worsening wall motion abnormality in at least one segment was considered positive for myocardial ischemia.

RESULTS: Significant CAD (stenoses of at least 50% diameter at angiography) was found in 119 patients (74%). Target heart rate was not reached in nine patients (6%). Overall sensitivity and specificity for detection of significant CAD were 89% and 84%, respectively. Diagnostic accuracy was 88%, and positive and negative predictive values were 94% and 73%, respectively. Overall sensitivity for detection of significant CAD in patients with single-, double-, and triple-vessel disease was 87%, 88%, and 100%, respectively.

CONCLUSION: High-dose stress cardiovascular MR imaging can be used for follow-up of patients after coronary revascularization procedures. Diagnostic accuracy is similar to stress cardiovascular MR imaging data for patients suspected of having CAD and compares favorably with that of other established noninvasive techniques.