Study on the left ventricular flow in patients with bileaflet prosthesis mitral valve by vector flow mapping using Doppler echocardiography

Abstract

Objective To compare the formation and evolution of left ventricular flow between the patients with the bileaflet artificial mechanical mitral valve and normal adult using vector flow mapping (VFM). Methods Thirty healthy controls and 30 severe mitral stenosis patients with bileaflet prosthesis mitral valve were involved. The left ventricular flow and the vortex description parameters were comparatively studied between two groups. Results Two small symmetric rotating vortexes and a big counter-clockwise rotating vortex appeared alternately in the left ventricular through cardiac cycle with control group. In case group,only large vortex could be seen in the mid-late diastolic and maximum vector velocity was faster than that in control group in statistics( P <0. 05). Especially the postoperative direction of blood flow was clockwise shif ting from the interventricular septum to the posterior and lateral left ventricular wall inversely to control group. Conclusions VFM can show the complex vortex flow patterns in left ventricular in the patients with bileaflet prosthesis mitral valve preliminarily and may be useful to assess and improve the function of prosthesis valve in future. Key words: Echocardiography; Heart valve, prosthesis; Ventricular function, left; Vector flow mapping