Effects of echocardiography-guided pacemaker parameters optimization in cardiac resynchronization therapy

Objective To investigate the effects of echocardiography-guided pacemaker parameters optimization in order to enhance the efficacy of cardiac resynchronization therapy(CRT).Methods Seventeen patients with chronic heart failure received biventricular resynchronous pacing therapy.A-V delay and V-V delay was optimized under the guiding of spectral Doppler echocardiography and tissue Doppler imaging.Results The indices of heart function in all patients were significantly improved after the treatment.The NYHA class of the patients was improved from class Ⅲ～Ⅳ to class Ⅱ～Ⅲ.Since PAV/SAV was optimized to 130-180/100-150 ms,left ventricular filling time(LVFT) was increased from (354±147)ms to (420±112)ms,mitral reflux (MR) was decreased from (8.41±4.55)cm2 to (5.36±4.71)cm2.After VV delay was optimized to 4-40ms,standard deviation of time to regional peak systolic velocity (Ts-SD-12) was decreased from (48.4±17.9)ms to (30.2±18.6)ms,left ventricular outflow tract velocity time integral(VTI LVOT) was increased from (20.6±9.0)cm/s to (26.1±3.1)cm/s.Conclusions Echocardiography-guided optimization of the pacemaker parameters is necessary in order to enhance the efficacy of CRT. Key words: Echocardiography; Heart failure,congestive; Cardiac resynchronization therapy