Incremental Value of Perfusion over Wall‐Motion Abnormalities with the Use of Dobutamine–Atropine Stress Myocardial Contrast Echocardiography and Magnetic Resonance Imaging for Detecting Coronary Artery Disease

Abstract

Recently, multimodality imaging has been demonstrated to improve the sensitivity of dobutamine stress for the diagnosis of coronary artery disease (CAD). We sought to determine the additional value of myocardial perfusion (MP) over wall-motion (WM) analysis for detecting CAD, using real time myocardial contrast echocardiography (RTMCE) and cardiovascular magnetic resonance (CMR), in the same group of patients. We studied 42 patients who underwent RTMCE and CMR during high-dose dobutamine stress with early injection of atropine. No difference was observed in the diagnostic accuracy of RTMCE and CMR for detecting angiographically significant CAD when considering WM analysis alone (73% [95% CI, 65-81] and 78% [95% CI, 70-84], respectively; P = NS) or combined analysis of WM and MP (80% [95% CI, 73-97] and 83% [95% CI, 77-90], respectively; P = NS). Combined analysis of WM and MP had higher sensitivity than the analysis of WM alone by RTMCE (88% [95% CI, 75-100] vs. 72% [95% CI, 54-90]) and by CMR (92% [95% CI, 81-100] vs. 80% [95% CI, 64-96]) with no differences in specificity. The association of abnormal WM and MP abnormalities during high-dose dobutamine-atropine stress had additional value for detecting CAD over the analysis of WM alone, both by RTMCE (χ(2) = 16.16-24.13; P = 0.005) and CMR (χ(2) = 12.73-27.41; P = 0.001). RTMCE and CMR using the same dobutamine-atropine stress protocol had comparable diagnostic accuracies for the detection of angiographically significant CAD. MP imaging had additional value over WM analysis for the diagnosis of CAD, both at RTMCE and CMR.