[Pathologic movements of the ventricular septum in complete block of the left branch of the bundle of His and their effect on left ventricular function].

Echocardiographic tools (M-mode and 2D-scanning) were applied to examine 83 patients with complete bundle-branch block and/or its anteroapical bifurcation block. Six types of abnormal ventricular septal motions associated with the intraventricular asynchronism typical of complete bundle-branch block and with the specific features of electric pulse propagation in the His-Purkinje system were identified. There was a reduction in left ventricular ejection fraction that is peculiar to Types I and VI abnormal ventricular septal motions, whereas in patients with complete bundle-branch block, it is associated with anteroapical bifurcation block. A moderate decrease in ejection fraction is more common for Types III and IV abnormal ventricular septal motions (despite the severity of cardiac disease). Complete bundle-branch block alone and in combination with anteroapical bifurcation block contributes to a decrease in left ventricular function and diminished myocardial contractility. Whether the severity of complete bundle-branch block affects cardiodynamics is discussed in the present paper.