Comparison of stress/rest myocardial perfusion tomography, dipyridamole and dobutamine stress echocardiography for the detection of coronary disease in hypertensive patients with chest pain and positive exercise test

OBJECTIVES Although different noninvasive tests have been proposed for dete cting coronary artery disease (CAD) in patients with hypertension and chest pain symptoms, the relative performance of the available techniques has no t been systematically assessed. BACKGROUND Patients with hypertension frequently complain of chest pain and exhibit ischemic-like ST segment changes on the exercise electrocardiogram (ECG). However, the specificity of such changes for predicting significant CAD is very low, because these patients often exhibit a normal coronary an giogram. METHODS In 101 patients with hypertension, chest pain and positive exercise EGG, we performed stress/rest myocardial single photon emission computed t omography with 99mTc-MIBI, dipyridamole and dobutamine stress echocardiogra phy and coronary angiography. All patients had normal global ventricular fu nction and 57 had left ventricular hypertrophy. All were kept on ACE inhibi tors during the study period. RESULTS No patients had significant side effects during perfusion scintigra phy. Dose-limiting side effects were observed in five patients with dipyrid amole and in seven patients with dobutamine. Only 56% of study patients exh ibited significant CAD. Sensitivity, specificity, accuracy, positive and ne gative predictive values were, respectively, 98%, 36%, 71%, 67% and 94% for perfusion scintigraphy, 61%, 91%, 74%, 90% and 64% for dipyridamole and 88 %, 80%, 84%, 85% and 83% for dobutamine stress echocardiography. CONCLUSIONS This study shows that stress echo in patients with hypertension yields a satisfactory diagnostic accuracy for identifying significant epic ardial CAD. Our results indicate that dobutamine might be superior to dipyr idamole. The low specificity of myocardial scintigraphy probably relates to the fact that this method traces perfusion abnormalities, not necessarily caused by epicardial CAD, possibly due to microvascular disease and not cau sing obvious wall motion abnormalities. (C) 1999 by the American College of Cardiology.