Prediction of the effectiveness of long term beta  blocker treatment for dilated cardiomyopathy by signal averaged electrocardiography

Abstract

AbstractsObjective-To determine whether the effectiveness of long term blocker treatment for idiopathic dilated cardiomyopathy can be predicted by signal averaged electrocardiography (ECG). Patients-31 patients with dilated cardiomyopathy and without bundle branch block were included in a retrospective study and 16 in a prospective study. Signal averaged ECG criteria for good response were defined as two or more of the following: QRS duration < 130 ms, RMS40 > 20 µV, LAS40 < 40 ms (sensitivity 81%, specificity 73%). In the prospective study, six of seven patients who met these criteria showed a good response to the blocker treatment, while eight of nine who did not showed a poor response ( 2 = 6.1, p < 0.02). The signal averaged ECG criteria gave a sensitivity of 86% and a specificity of 89% for predicting the eVectiveness of blocker treatment. Conclusions-A signal averaged ECG might be useful in predicting the eVectiveness of blocker treatment for dilated cardiomyopathy. Methods-

Current issues regarding beta-adrenergic blockade in patients with congestive heart failure: Patient selection, non-selective versus selective blockade, management of adverse effects, and indications for withdrawal of therapy

“…Yamada et al found that intercellular fibrosis on myocardial biopsy predicted a poor response to metoprolol therapy. Moreover, they reported that such fibrosis could be estimated by means of signal averaging, and suggested this noninvasive method could predict clinical response to metoprolol therapy with a sensitivity of 85% and a specificity of 91% [38][39][40]. Similarly, Suwa et al demonstrated that myocardial integrated ultrasonic backscatter imaging, useful in delineating myocardial fibrosis, could help predict response to therapy with bisoprolol [41].…”