Panayotis K Vlachakis, Panagiotis Theofilis, Maria Drakopoulou, Christos Fragoulis, Panagiotis Dourvas, Paschalis Karakasis, Ioannis Kachrimanidis, Ioannis Leontsinis, Skevos Sideris, Konstantinos Tsioufis, Efstathios Manios, Konstantinos Toutouzas
In CCAVB, permanent pacing is associated with a clinically meaningful, lifelong burden of cardiomyopathy, mortality, and device-related complications. The wide variation in outcome definitions and the largely retrospective evidence base limit firm conclusions, underscoring the need for prospective multicentre studies with standardized definitions.
BACKGROUND: Congenital complete atrioventricular block (CCAVB) requires pacing from early life, yet the long-term burden of pacing-induced cardiomyopathy (PICM), mortality, and device-related complications has not been quantitatively synthesized.
OBJECTIVE: To determine the incidence of PICM, mortality, and device-related complications after permanent pacemaker implantation in patients with CCAVB.
METHODS: PubMed, Scopus, and Web of Science were searched from inception through February 2026. Longitudinal studies enrolling patients with isolated or predominantly isolated CCAVB undergoing permanent pacemaker implantation, reporting PICM or left ventricular (LV) dysfunction, and with ≥6 months' follow-up were included. PICM was defined as LV ejection fraction < 50% or study-specific LV dysfunction. Pooled event rates were estimated using random-effect meta-analysis.
RESULTS: Eighteen studies including 1,233 paced patients were included. The pooled incidence of PICM was 13.3% (95% CI 9.9-17.7%; I2=68%). Sensitivity analyses across alternative definitions yielded similar estimates (12.1% to 13.4%). PICM onset occurred earlier in antibody-positive than non-immune populations (mean 1.9 vs. 17.4 years; p=0.009). All-cause mortality was 6.3% (95% CI 3.8-10.3%; I2=75%), lead failure 9.5% (95% CI 4.2-19.9%; I2=85%), and device infection 8.2% (95% CI 4.4-15.0%; I2=49%), including 4.2% deep/device-related infection (95% CI 2.1-8.2%; I2=20%). Longer follow-up showed a non-significant trend toward higher PICM incidence (β=+0.025 per year; p=0.080).
CONCLUSION: In CCAVB, permanent pacing is associated with a clinically meaningful, lifelong burden of cardiomyopathy, mortality, and device-related complications. The wide variation in outcome definitions and the largely retrospective evidence base limit firm conclusions, underscoring the need for prospective multicentre studies with standardized definitions.