Affiliation:
1. Department of Cardiology National University Heart Centre Singapore Singapore
2. Department of Medicine, Yong Loo Lin School of Medicine National University Singapore Singapore Singapore
3. Department of Cardiology Ng Teng Fong General Hospital Singapore Singapore
Abstract
AbstractIntroductionClinical outcomes of long‐term ventricular septal pacing (VSP) without His‐Purkinje capture remain unknown. This study evaluated the differences in clinical outcomes between conduction system pacing (CSP), VSP, and right ventricular pacing (RVP).MethodsConsecutive patients with bradycardia indicated for pacing from 2016 to 2022 were prospectively followed for the clinical endpoints of heart failure (HF)‐hospitalizations and all‐cause mortality at 2 years. VSP was defined as septal pacing due to unsuccessful CSP implant or successful CSP followed by loss of His‐Purkinje capture within 90 days.ResultsAmong 1016 patients (age 73.9 ± 11.2 years, 47% female, 48% atrioventricular block), 612 received RVP, 335 received CSP and 69 received VSP. Paced QRS duration was similar between VSP and RVP, but both significantly longer than CSP (p < .05). HF‐hospitalizations occurred in 130 (13%) patients (CSP 7% vs. RVP 16% vs. VSP 13%, p = .001), and all‐cause mortality in 143 (14%) patients (CSP 7% vs. RVP 19% vs. VSP 9%, p < .001). The association of pacing modality with clinical events was limited to those with ventricular pacing (Vp) > 20% (pinteraction < .05). Adjusting for clinical risk factors among patients with Vp > 20%, VSP (adjusted hazard ratio [AHR]: 4.74, 95% confidence interval [CI]: 1.57–14.36) and RVP (AHR: 3.08, 95% CI: 1.44‐6.60) were associated with increased hazard of HF‐hospitalizations, and RVP (2.52, 95% CI: 1.19–5.35) with increased mortality, compared to CSP. Clinical endpoints did not differ between VSP and RVP with Vp > 20%, or amongst groups with Vp < 20%.ConclusionConduction system capture is associated with improved clinical outcomes. CSP should be preferred over VSP or RVP during pacing for bradycardia.