Abstract 597: Prospective Randomized Comparison of Conventional Stress Echocardiography and Real Time Perfusion Stress Echocardiography in Detecting Angiographically Significant Coronary Artery Disease
Background. Although real time perfusion (RTP) imaging has been shown to detect myocardial perfusion defects during exercise (ESE) or dobutamine stress echocardiography (DSE), its incremental value over conventional stress echocardiography (CSE) has not been demonstrated in a prospective randomized setting.
Methods. We prospectively randomized 1227 patients (pts) referred for either DSE or ESE to either CSE (using harmonic imaging) where contrast is used only for the FDA-approved indication to improve left ventricular opacification, or RTP imaging (using low mechanical index perfusion imaging to examine both myocardial perfusion (MP) and wall motion (WM). MP and WM were assessed by one of five different experienced reviewers in each coronary artery territory at rest and peak stress.
Results. A total of 624 pts were assigned to CSE (351 DSE, 277 ESE), and 603 to RTP stress echo (398 DSE, 209 ESE). MP was abnormal despite normal WM in 30 of the abnormal RTP studies (17%). Abnormal studies were significantly higher in the group randomized to RTP (31% positive rate versus 18% in the CSE group; p<0.0001). A total 103 pts had coronary angiography within 60 days following the stress echo (72 RTP, 31 CSE). There were no differences between RTP and CSE pts going to angiography with regard to age, prior revascularization, risk factors, or resting ejection fraction. The prevalence of disease among the patients who received angiography was 77%. The sensitivity and positive predictive values (PPV) for detection of >50% diameter stenoses by patient, as well as for detecting specific coronary artery territory (CAT) disease are shown in the Table⇓. Despite a significantly higher number of abnormal studies, overall sensitivity and PPV of RTP was not different than CSE
Conclusions. Examining both MP and WM with RTP imaging increases the detection of coronary artery disease during both dobutamine and exercise stress echocardiography, without affecting the positive predictive value of the test.