Evaluation of left ventricular systolic hemodynamics in patients with hypertrophic cardiomyopathy using vector flow mapping

Abstract

Objective To investigate the left ventricular(LV) systolic hemodynamics and the distribution of blood flow in patients with hypertrophic cardiomyopathy(HCM) by vector flow mapping(VFM).MethodsThirty-five random non-obstructive HCM patients(case group) and forty healthy volunteers (control group) were enrolled.Peak systolic velocity (Vs),peak systolic flow (Fs) and total systolic negative flow (SQ-) of two groups were compared.Velocity vector,streamline and vortex distribution of two groups were observed.Results Vs,Fs,SQ- of the control group and Vs,Fs of the case group all showed a decreasing trend from the basal segments to the apical segment(P<0.05).SQ- of the case group lost this decreasing tendency.Vs,Fs of all segments and SQ- of the middle and apical segment of the case group were higher than those of the control group.SQ- of the basal segment of the case group were significantly lower than that of the control group(P＜0.01).Distribution of blood flow:The velocity of blood flow was faster in the case group than that in the control group and the direction was disordered.The streamlines of the case group were discontinuous,and vortexes in the case group were more than that in the control group.Conclusions VFM technology could quantitatively evaluate LV systolic hemodynamics in patients with HCM,and can clearly show the distribution of blood flow. Key words: Echocardiography; Cardiomyopathy,hypertrophic; Ventricular function,left; Vector flow mapping