Intraventricular Isovolumic Relaxation Flow Patterns Studied by Using Vector Flow Mapping.

Abstract

The purpose of this study was to characterize isovolumic relaxation flow (IRF) in the left ventricle (LV) in patients with a wide spectrum of LV dysfunction. Color Doppler flow imaging was performed in 61 patients with coronary artery disease, 29 patients with dilated cardiomyopathy, and 41 healthy controls. Vector flow mapping was used to analyze the Doppler data. IRF patterns were divided into three types: pattern A, an apically directed flow; pattern B, a bidirectional flow with small scattered vortices; and pattern C, a large vortex persisting throughout the entire isovolumic relaxation (IVR) period. All controls demonstrated an IRF corresponding to pattern A. Of the 90 patients, 42 demonstrated IRF as pattern A, 26 as pattern B, and 22 as pattern C. There were significant differences among the subgroups of patients with different IRF patterns and the control group in LV-ejection fraction, size, wall-motion score index, apical wall-motion score index, systolic and diastolic mitral annular velocities, ratio of the mitral inflow E velocity to early diastolic mitral annular velocity (E/e'), and left atrial diameter (all P < 0.05). In the patient group, a higher wall-motion score index independently predicted the IRF pattern. In patients with severe LV dysfunction, a higher E/e' ratio was the independent predictor of the persistence of a large vortex during the IVR period. The IRF pattern is associated with LV function. A large intraventricular vortex persisting during the IVR period should be indicative of increasingly depressed LV function.