Ventricular dysfunction after permanent pacemaker implantation in children - what are the implications?

Introduction Children (<18 years of age) account for less than 1% of patients requiring permanent pacemaker implantation (PPI), but form a complex subset of population due to technical difficulties, higher prevalence of structural abnormalities and higher rates of reinterventions. Post-pacemaker ventricular dysfunction is seen in around 10-15% and is related to the electrical and mechanical ventricular dyssynchrony. However, similar data is lacking from patients who underwent permanent pacemaker implantation below 18 years of age. Methods We retrospectively analysed 235 patients who underwent PPI below 18 years of age, for development of ventricular systolic dysfunction, defined by ejection fraction below 50% of the systemic ventricle. Results Male: female ratio was 1.1:1, with median age of implantation being 7 years. 43.4% underwent epicardial PPI, and the commonest indication being congenital complete heart block (50.2%) followed by post-operative CHB (28.1%). 65.5% underwent VVI pacemaker implantation. 41.3% had associated congenital heart disease out of which ventricular septal defect was commonest (20.6%) followed by atrial septal defect (18.6%). Over a median follow-up of 8 years, 15 (6.38%) patients developed ventricular dysfunction, with systemic ventricle of RV morphology, younger age at implantation, maternal ANA positivity, presence of post-operative CHB, associated congenital heart disease and epicardial PPI being major predictors. Five (2.1%) patients required hospitalization for heart failure, while 2 underwent upgradation to CRT. Those with ventricular dysfunction had higher mortality than those who had normal ventricular dysfunction (40% vs 1.5%, p <0.01). There was no association of ventricular dysfunction with the duration of pacing (p = 0.25), the percentage of pacing (p = 0.25) or number of chambers paced (p = 0.38). Conclusion Ventricular dysfunction is seen in 6.38% of patients who underwent PPI below 18 years of age, over a median duration of 8 years. It was associated with higher mortality, while younger age at implantation, maternal ANA positivity, presence of post-operative CHB, associated congenital heart disease and epicardial PPI were major predictors for development of ventricular dysfunction.