Assessment of left ventricular fundion after mitral valve replacement by tissue Doppler imaging

Objective To evaluate the clinical value of tissue Doppler imaging(TDI)in assessing left ventricular(LV)function after mitral valve replacement(MVR).Methods Forty-five patients having their implantations for more than three months were examined by echocardiography and divided into atrial fibrillation group(AF group,n=21)and sinus rhythm group(SR group,n=24).Thirty normal volunteers served as control group.Left atrium and ventricle indexs of cardiac function and mitral inflow velocity(E)were measured by two dimensional and Doppler echocardiography,and TDI-derived systolic mitral annular velocity(Sm),diastolic mitral annular velocity(Em)and isovolumic relaxation time(IVRT)were measured at the septal and lateral corners of mitral annulus from the apical four-chamber view.Then E/Em ratio was calculated.Results ①Compared with control group,Sm and Em in MVR group were significantly lower and IVRT was higher(P＜0.001),however there were no significant differences between AF group and SR group.② The E/Em ratio in MVR group was significantly higher than that in control group(P＜0.001)and positively correlated with IVRT.The best cutoff value for E/Em ratio was increased of 15 which yielded the sensitivity and specificity in predicting LV diastolic dysfunction were 91.11% and 90.32%,respectively.The area under the ROC curve was 0.9548±0.0402.Conclusions TDI-defived indexes(Sm,Em)can assess LV function accurately and the E/Em ratio,an estimate of myocardial relaxation and LV filling pressures,can be used to evaluate left ventricular diastolic function after MVR. Key words: Echocardiography; Heart valve prosthesis implantation; Ventricular function,left; Tissue Doppler imaging