Abstract 10823: Antiarrhythmic Effect of Cardiac Resynchronization Therapy With Triple-site Biventricular Stimulation
Background: Cardiac resynchronization therapy (CRT) with triple-site ventricular stimulation (Tri-V), involving double LV and single RV pacing has been reported to be feasible and more beneficial than standard CRT with dual-site ventricular stimulation (Bi-V). However, the antiarrhythmic effect of Tri-V is poorly understood.
Objectives: This study aims to evaluate the effect of CRT on ventricular arrhythmias with Tri-V.
Methods: Over a period of 3.5 years, 58 consecutive patients with New York Heart Association class II-IV heart failure, an LV ejection fraction of ≤0.35, and a QRS interval of ≥120 ms were enrolled. Acute hemodynamic responses to temporary dual-site and triple-site ventricular pacing were evaluated by assigning patients to a Bi-V or Tri-V group. ECG parameters (QT interval, JT interval, and transmural dispersion of repolarization [TDR]) were measured over time after CRT. Spontaneous ventricular arrhythmias detected by telemetry were reviewed and confirmed.
Results: During a mean follow-up of 481 days after implantation, ventricular arrhythmias occurred in 2 of 22 patients in the Tri-V group and 14 of 36 patients in Bi-V group. Tri-V was thus associated with a decreased ventricular arrhythmia risk (p = 0.044). Multivariate Cox analysis showed that Tri-V was an independent predictor of ventricular arrhythmias (hazard ratio, 0.13; 95% confidence interval, 0.029-0.610; p = 0.009). Ventricular repolarization indices at 6 months from baseline were significantly shortened in Tri-V compared to Bi-V (QT, -23.6 vs. -14.1%, p = 0.008; JT, -21.4 vs. -7.7%, p = 0.005; TDR, -39.9 vs. -17.0%, p < 0.001).
Conclusions: In conclusion, Tri-V reduced ventricular arrhythmias during long-term follow-up compared with Bi-V. Improvements in ventricular repolarization indices associated with Tri-V might be due to antiarrhythmic effects.
- © 2012 by American Heart Association, Inc.