Assessment of the effects of cardiac resynchronization therapy in patients with dilated cardiomyopathy by threedimensional speckle tracking imaging

Abstract

Objective To evaluate the effects of cardiac resynchronization therapy (CRT) on improving left ventricle (LV) function and LV asynchrony in patients with dilated cardiomyopathy(DCM)using three-dimensional ultrasound speckle tracking imaging(3D-STI).Methods Twenty one patients with DCM and 25 normal subjects were enrolled in this study.Parameters including LV mean longitudinal peak strain (MLS),LV mean circumferential peak strain (MCS),LV mean radial peak strain (MRS),LV ejection fraction(3D-LVEF),maximal temporal difference in area strain of LV 16 segments (A-MaxTs) and its standard deviation (A-Ts-SD) were investigated by 3D-STI.LV ejection fraction (ECT-LVEF) and LV phase angle width (LVW) were obtained by radionuclide ventriculography and phase image analysis.Results The indexes of MLS,MCS,MRS and 3D-LVEF were decreased and A-MaxTs,A-Ts-SD were prolonged in DCM group compared with those of control group.There was a slightly improvement in MRS and ECTLVEF 1 week after CRT,but other Parameters including MLS,MCS,A-MaxTs,A-Ts-SD and 3D-LVEF had no significant change.Compared with corresponding values before and 1 week after CRT,all parameters (MCS,MRS,A-MaxTs,A-Ts-SD,3D-LVEF and ECT-LVEF) were further improved 6 months after CRT.MLS,MCS,MRS and 3D-LVEF had good relationship with ECT-LVEF,and A-MaxTs,A-Ts-SD had good relationship with LVW in DCM group.Conclusions 3D-STI is a simple and accurate method for evaluating effects of CRT on improving LV function and LV asynchrony in patients with DCM. Key words: Echocardiography, three-dimensional; Cardiomyopathy, dilated; Ventricular function, left; Speckle tracking imaging