986-78 Improved Detection of Coronary Artery Disease in Hypertensive Patients by Dobutamine Stress Echocardiography

Abstract

From a cohort of 43 hypertensive patients (BP > 160/95 mmHg) who had undergone coronary angiography for the diagnosis of chest pain, the results of exercise testing (EXT) and dobutamine stress echocardiography (Echo) were compared to assess their relative roles for the detection of coronary artery disease. These selected patients had no electrocardiographic evidence of left ventricular hypertrophy or basal ST-T changes. Graded stress dobutamine (5–40 μ g/kg/min) Echo was carried out until end-points were achieved. Graded treadmill EXT was performed using the Bruce protocol. A coronary artery lesion >50% was considered significant. Left ventricular mass index was calculated by Echo and 28 out of the 43 patients had increased left ventricular mass index. Coronary artery disease was present in 29, of whom, 21 had multi-vessel disease, and 14 patients had normal coronary anatomy. Sensitivity and specificity for the detection of coronary artery disease by dobutamine Echo were 93% and 100%, and for the EXT these were 72% and 29%, respectively. Similarly, for detection of multi-vessel disease the values were 82% and 95%, for dobutamine Echo and 77% and 33% for EXT, respectively. Logistic regression analysis revealed that EXT was a poor predictor of coronary artery disease (p = 0.09) while dobutamine Echo was significantly better (p < 0.001). When patients with increased left ventricular mass index were excluded, prediction of coronary anatomy by EXT improved only marginally (p = 0.4) while dobutamine Echo remained unchanged (p < 0.001). Stress dobutamine Echo is safe in hypertensive patients and is probably the method of choice for evaluating underlying coronary artery disease.