Value of different myocardial response patterns to dobutamine stress in detecting coronary artery disease in patients with severe left ventricular dysfunction

Background: This study was conducted to determine the value of different myocardial response patterns to dobutamine stress in the detection of coronary artery disease in patients with dilated cardiomyopathy. Materials and methods: Dobutamine echocardiography was performed on 72 patients with left ventricular dysfunction. Coronary artery disease was documented by coronary angiography in 52 of these patients. Wall motion response patterns were classified as no response, sustained improvement, increase in wall motion score, or biphasic response. Results: In segments of akinesis, the sensitivity and specificity of detecting significant coronary stenosis were 14% and 78%, respectively, for the increase in wall motion score, 13% and 91% for the biphasic response, and 68% and 46% for no response. In segments of hypokinesis, the sensitivity and specificity were 45% and 97%, respectively, for the increase in wall motion score, 18% and 98% for the biphasic response, and 27% and 66% for no response. In the segments of normal motion, the sensitivity and specificity were 68% and 85%, respectively, for the increase in wall motion score. The specificity of the no response pattern was too low to increase the diagnostic benefit in the clinical evaluation. Conclusion: For the detection of coronary artery disease in dilated cardiomyopathy, the observation of a biphasic response in hypokinetic or akinetic segments, and a response of increase in wall motion score in normokinetic or hypokinetic segments, is optimal.