Cardio-Neuoromodulation in a Child with Congenital Central Hypoventilation Syndrome – A new therapeutic option

Congenital Central Hypoventilation Syndrome (CCHS) is a rare disease characterized by autonomic nervous system (ANS) dysregulation. It is caused by mutations in the PHOX2B gene with an autosomal dominant inheritance. Central hypoventilation is the most prominent and clinically important presentation; however, sinus pauses complicate 20-80% of CCHS patients due to the ANS dysfunction. Pauses > 3 seconds are associated with increased risk of sudden death, hence pacemaker implantation is indicated.

Asymptomatic prolonged sinus pauses were found in a chronically ventilated nine-year-old boy with CCHS on routine Holter recordings with an intact atrioventricular (AV) conduction. In an attempt to avoid pacemaker implantation, he underwent a right sided cardio-neuromodulation by ablating the parasympathetic ganglionated plexi area using radiofrequency energy. Pre- and post-procedure injection of Atropine were consistent with successful endpoint. An implantable loop recorder (ILR) documented a severe bradycardic event (R-R interval 7.1 seconds) two days later. Simultaneous Holter recording revealed normal sinus rhythm with a high-grade second-degree AV block as the cause. A successful second Cardio-neuromodulatory procedure with inhibition of the parasympathetic innervation to the AV node was performed. During 9 months follow-up with an ILR and repeated Holter recordings, no bradycardic episodes were observed.

This is the first case of right sided parasympathetic ganglion ablation in a child. This approach offers a novel therapeutic option for children with symptomatic, vagally mediated sinus pauses and specifically in children with ANS dysregulation diseases such as CCHS. It may prevent the need for pacemaker implantation, with its associated complications and morbidity.