Basal Asynchrony and Resynchronization with Biventricular Pacing Predict Long-Term Improvement of LV Function in Heart Failure Patients

Biventricular pacing (BiV) is emerging for patients with dilated cardiomyopathy (DCM) and asynchrony. We measured basal asynchrony and early resynchronization by radionuclide angioscintigraphy (RNA) in order to predict long-term evolution of ventricular function after BiV. Thirty-four patients (NYHA Class III–IV,65.4 ± 11 years) with large QRS(179 ± 18 ms)were implanted with BiV and studied by RNA before (D0), at day 8 (D8), and during follow-up(20 ± 7 months). We calculated left and right ejection fractions, the interventricular dyssynchrony (TRVLV), and the apicobasal dyssynchrony (Tab). LVEF improved from20.2 ± 8.1%(D0) to27.1%± 12.6%(follow-up,P 15% and a significant interventricular dyssynchrony (TRVLV > 60 ms) at D0 have a sensitivity of 79% and a positive predictive value of 83% to predict an improvement of LVEF superior to 5% at follow-up. In DCM patients, BiV resynchronizes ventricles early and in the long-term, while RVEF and LVEF improve progressively. Patients with large electromechanical dyssynchrony benefit most from BiV. (PACE 2003; 26:1815–1823)