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Changes in Systolic and Diastolic Function Indexes Throughout Dobutamine Stress Echocardiography in Healthy Volunteers and Patients with Ischemic Heart Disease

Background and Hypothesis: Dobutamine stress echocardiography is a well‐established diagnostic method for investigating patients with suspected ischemic coronary disease. A positive test result is based on systolic parameters, but left ventricular filling parameters also are affected by myocardial ischemia. The aim of the present study was to study changes in both systolic and diastolic left ventricular variables throughout the test, including the period following it. Methods and Results: Seven healthy control subjects (group I), 10 patients with chest pain but without significant coronary stenosis (group II), and 17 patients with significant coronary stenosis (group III) were entered in the study. Dobutamine stress echocardiography was performed according to a preset standardized protocol. Two‐dimensional echocardiography and transmitral pulsed‐Doppler images were stored for later analysis at rest, low dose, peak dose, and 5 minutes after termination of the dobutamine infusion. The wall motion score index increased from rest to low dose by 6.7%± 6.4% (P < 0.05) and to the peak dose by 39.1%± 9.9% (P < 0.001) in all three groups. The increase from rest to peak dose was significantly higher in groups I and II than in group III (P < 0.01). There was a significant increase in the atrial velocity‐time integral (A‐VTI) at peak dose in groups I and II (64.8%± 52.1% and 103.8%± 68.7%, respectively; P < 0.05 and < 0.001), but no change in group III was noted. At the peak dose, A‐VTI was significantly greater in groups I and II than in group III (P < 0.05). Among the 17 patients with proved coronary stenosis, 15 (88.2%) had a positive systolic response and 14 (82.3%) had a positive diastolic response, expressed as an A‐VTI increase of ± 2.5 cm. Among patients without significant stenosis, 9 (52.9%) had a negative systolic response, and 12 (70.6%) had a negative diastolic response. Conclusion: Changes in systolic parameters are the most sensitive ones to identify in a patient with significant coronary stenosis, but diastolic changes indicated by changes in A‐VTI from rest to peak dose might contribute to decreasing the number of false‐positive dobutamine stress echocardiography tests.