Patterns of Flow Within the Dilated Cardiomyopathy Left Ventricle: Color Flow Doppler Observations

Abstract

Study of the pathways of intraventricular flow by pulsed Doppler and color flow Doppler has shown that, in normal individuals, a broad strong stream flows into the left ventricular chamber from the mitral annulus to the apex during early rapid and late (atrial) ventricular filling phases; in systole, a broad rapid stream from the apex to the aortic orifice is dominant. In dilated cardiomyopathy, flow velocities are slower, and the typical pattern is a circular type of diastolic flow along the lateral left ventricular wall toward the apex and then from the apex to the aortic orifice along the septum. The systolic flow pattern is also different in dilated cardiomyopathy; in addition to the flow along the septum toward the aortic orifice, some blood flows in a circular manner back to the apex along the lateral wall. An important aspect of abnormal flow patterns in dilated dysfunctional left ventricular chambers is their association with a tendency to thrombus formation. Thus, the pathophysiology of abnormal intraventricular flow patterns may have academic but also therapeutic implications. (ECHOCARDIOGRAPHY, Volume 8, March 1991)