Abstract 10932: The Relationship of Percent Biventricular Pacing to Ventricular Arrhythmias and Reverse Remodeling Post Cardiac Resynchronization Therapy
Background: A high % of biventricular pacing (BiVP) has been associated with improved survival free of heart failure hospitalization, but the impact of % BiVP on ventricular arrhythmias and reverse remodeling is unknown.
Methods: This study examined 227 patients with cardiac resynchronization therapy defibrillator (CRT-D) implantation for standard indications. Kaplan Meier analysis was used to determine the optimal BiVP% cutoff associated with incidence of appropriate device therapy for VT/VF. LV reverse remodeling was defined as an absolute increase in ejection fraction of ≥ 5% at 6 month follow up.
Results: The optimal BiVP threshold associated with time to first episode of treated VT/VF was ≥ 99% (p=0.015, Figure). BiVP of ≥ 99% was achieved in 91 study patients. This cutoff was also associated with improved reverse remodeling (76 vs. 52% of patients, p < 0.0001). Patients with ≥ 99% BiVP were more likely to be female (33% vs. 15%, p < 0.001), had less chronic atrial fibrillation (12% vs. 31% p < 0.001), lower baseline LVEDD (60.5 ± 9.5 vs. 63.2 ± 8.5mm, p = 0.03) and LVESD (52.9 ± 9.4 vs. 55.5 ± 8.9mm, p = 0.04).
Conclusion: A biventricular pacing threshold of ≥ 99% is predictive of reduced incidence of ventricular arrhythmias and improved reverse remodeling after CRT implantation. These findings demonstrate the importance of achieving a very high %BiVP.
- © 2013 by American Heart Association, Inc.