Objective: To quantitatively assess the effects of cardiac resynchronization therapy (CRT) in patients with advanced congestive heart failure by real-time 3-dimensional(3D) echocardiography (RT-3DE).
Methods: Eighteen patients with advanced congestive heart failure underwent CRT with New York Heart association(NYHA) class III and IV and wide QRS complex (>120 ms) were included (17 dilated cardiomyopathy and 1 ischemic cardiomyopathy). Before CRT and 8 months after CRT, the clinical and RT-3DE parameters and outcome were analyzed.
Results: The biventricular pacemaker was successfully implanted in 17 patients (94.4%). Compared with before CRT, NYHA class of patients decreased by 1.5 class (P < 0.01), left ventricular ejection fraction increased by 25% (P < 0.01), left ventricular end systolic volume decreased by 38% (P < 0.01), left ventricular systolic dyssynchrony index (SDI) improved significantly (14.2% before CRT vs. 9.8% after CRT, P < 0.01 ) post CRT. Change in SDI and change in LVEF was positively correlated (r = 0.62, P < 0.01) . The procedure complications and outcome during and after CRT included coronary sinus dissection (n = 1), left ventricular lead dislodgement (n = 1), phrenic nerve stimulation (n = 1), sudden cardiac death (n = 1). Three non-response patients were complicated with atrial fibrillation, nonspecific intraventricular block and dilated cardiomyopathy with postero-lateral scar tissue.
Conclusions: CRT could improve the cardiac function, correct the mechanical desynchronization and reverse left ventricular remodeling in patients with congestive heart failure, and SDI quantification by RT-3DE could predict increase of LVEF after CRT, however, there were complications related to the implantation procedure and possibilities of non-response.