Pediatric/Adult Congenital Heart Disease -> Pediatric Cardiology D-AB15 - Pacing in Patients with Congenital Heart Disease (ID 44) Abstract


Background: Ventricular pacing (Vp) for subjects with a single ventricle (SV) has been associated with increased risk of transplant or death.
Objective: To quantify the absolute risk of Vp in subjects with SV, and identify factors associated with adverse paced outcome.
Methods: Multi-center international study (19 centers/7 countries). Vp subjects with SV (2000-2018) were matched by age, sex, era and SV morphology to SV controls without pacing.
Results: The Vp cohort consisted of 215 patients: age at implant 5.9yr (IQR 1.4-13yr), 107 (50%) right SV, Vp burden 89% (IQR 9-100%) with median follow-up 6.2yr (IQR 3-11yr). 57 (27%) developed Fontan failure, including 36 deaths.
Controls, matched for age and ventricular morphology, were identified for 139 Vp patients. At baseline, the Vp group had worse AV valve regurgitation (median ‘moderate’ versus ‘mild’, p=0.02) and NYHA class (median 3 versus 2, p=0.01). On multivariate Cox regression (MCR) analysis of matched pairs only, pacing remained associated with a greater risk of death/transplant (HR 18 (95% CI 3-34, p<0.001)) and Fontan failure (HR 6.1, p<0.001).
Within the Vp cohort only (n=215), risk factors for death/transplant on MCR were poor function at baseline (HR 1.4, 95% CI 1.1-1.8, p=0.007) and free wall pacing (HR 2.8, 95% CI 1.4-5, p=0.003), but not right SV, age at Fontan or VVI pacing. Vp burden demonstrated a bimodal distribution. On univariate analysis, Vp>40% and Vp>99% were associated with outcome (HR 2.1, p=0.03 and HR 1.8, p=0.04 respectively).
Conclusion: SV patients requiring Vp have an increased risk of transplant and death. Pacing lead location and Vp burden may be important modifiers.