Value of rapid beta-blocker injectionat peak dobutamine-atropine stressechocardiography for detection of coronary artery disease

Objectives We studied the value of a rapid beta-blocker injection at peak dobutamine-atropine stress echocardiography (DASE) for the detection of coronary artery disease (CAD). Background The presence of tachycardia and hyperdynamic wall motion may make it difficult to recognize a new wall motion abnormality (NWMA) at peak stress. Methods We studied 101 patients (mean age 58.2 ± 9.8 years) who underwent effective DASE and coronary angiography. All patients received a rapid intravenous injection of metoprolol immediately after peak DASE image acquisition. Positivity in combined peak plus post-metoprolol images was defined when there was only peak NWMA, maintenance of peak NWMA, or NWMA detected only after metoprolol injection. Significant CAD was defined as ≥50% stenosis by quantitative angiography. Results There were 37 patients without and 64 with CAD. The sensitivity, specificity, accuracy, and positive and negative predictive values for the detection of CAD at peak stress were 84%, 92%, 87%, 95%, and 77%, respectively. Five patients with CAD had negative peak images that became positive only after metoprolol. Extension of peak NWMA during metoprolol was observed in 14 patients, and multivessel CAD was detected in 10 of them. The sensitivity, specificity, accuracy, and positive and negative predictive values for peak plus metoprolol images were 92%, 89%, 91%, 94%, and 87%, respectively. Conclusions The use of metoprolol injected at peak of dobutamine infusion improved the detection of CAD by DASE.