Thirty four patients with LBBB or RBBB on EKG and 14 patients with cardiomyopathy documented by endomyocardial biopsy were studied by impedance cardiography for detecting the unusual pattern of the first derivative of impedance cardiogram. 100 normal subjects were included in this study as a control group. The high incidence of abnormal impedance cardiogram(The abnormal rate of dz/dt) in the patient group was found 41 in patients with LBBB was 93% RBBB was 8196; cardiomyopathy(CM)was 86% .However

there was 9% in the normal subjects only. Compared the results of patient group with the control group

there was highly significant (P<0.001)The sensitivity of impedance cardiogram for detecting abnormal rate of dz/dt in CM was 93% and specificity was 91% This abnormal pattern of impedance cardiogram may considered as a result from dyssynergy of left ventricular contraction. Therefore

the impedance tracing would become of interest for its simplicity and non-invasion in detecting hidden abnormalities of left ventricular contraction. Profably

it could be a compemental tool for early disgnosis of coronary artery disease and cordiomyopathy