Abstract 10994: Heart Failure in Patients with Sick Sinus Syndrome Treated with Single And Dual Chamber Pacing - No Association with Pacing Mode or Right Ventricular Pacing Site
Introduction In the DANPACE trial, patients with sick sinus syndrome (SSS) were randomized to single lead atrial (AAIR) or dual chamber (DDDR) pacing. Previous studies indicate that right ventricular (RV) pacing, especially from an RV apical (RVA) lead, may lead to the development of heart failure (HF). In the current study, we investigated the occurrence of HF during long-term follow-up in patients randomized to AAIR or DDDR pacing. Also, we investigated the effects of percentage of RV pacing (%VP) and the effects of RV pacing site on HF.
Methods We analysed data from 1,415 patients, included in the DANPACE trial.
Patients were classified as having developed HF if in NYHA (New York Heart Association) functional class IV or if two or more of the following three indicators were present at follow-up: Oedema; Dyspnoea; NYHA class III. Hospitalizations for HF were recorded. The %VP during follow-up was obtained from DDDR pacemakers. RV leads were categorized as localized in the RVA or at the septum (RVS)/outflow tract (RVOT).
Results A total of 707 patients were randomized to AAIR pacing, and 708 to DDDR pacing. Age was 73±11.3 years, 913 (65%) were female. Mean follow-up was 5.4 ± 2.4 years. In the AAIR group, 170 patients developed HF during follow-up vs. 169 patients in the DDDR group, hazard ratio (HR) 0.98, 95 % confidence interval (CI) 0.79-1.22, p = 0.87. Hospitalization for HF occurred in 27 patients in the AAIR group vs. in 28 patients in the DDDR group, HR 1.05, 95 % CI 0.62-1.79, p = 0.84. The incidence of HF was not associated with %VP (fractional polynomial vs. no relationship, p = 0.57). Among DDDR patients, 146/512 patients (29%) with RVA leads developed HF vs. 28/161 patients (17%) with RVS/RVOT leads, HR 0.67, 95% CI 0.45-1.00 P =0.05. After adjusting for baseline characteristics, the effect of pacing lead localization was still not significant (risk of HF with RVS/RVOT, HR 0.72, 95% CI 0.48-1.09, p = 0.12).
Conclusions In patients with SSS, there is no difference in HF between AAIR and DDDR pacing. HF is not associated with %VP, and there is no association between RVA and RVOT pacing. These findings suggest that DDDR pacing is without an increased risk of HF in patients with SSS.
- © 2011 by American Heart Association, Inc.