Heart transplantation for pediatric patients with malignant arrhythmias: Indications and outcomes

Background: Arrhythmias can lead to cardiac arrest and heart failure. When intractable, heart transplantation (HTX) can become the only viable treatment. This rare high-risk cohort has not been reported as a distinct group. Objective: The purpose of this study was to characterize the outcomes of pediatric patients listed for HTX with the primary indication being malignant arrhythmia (MA). Methods: Using the Pediatric Heart Transplant Society prospective registry, we identified all patients younger than 18 years listed between 2014 and 2022. MA as the listing indication was categorized into primary tachyarrhythmia (PT), inherited arrhythmia (IA), congenital heart disease, and cardiomyopathy (CM) with secondary arrhythmia. Demographic, listing, and transplant data were analyzed. Results: Among 4630 patients listed and 3317 transplanted, MA was the indication in 63 (1.4%) and 49 (1.5%), respectively. Patients with MA were categorized as PT in 11 (17%), IA in 4 (6%), congenital heart disease in 6 (10%), and CM in 42 (67%). Compared with the non-MA cohort, patients listed for MA were older (mean age 10.6 ± 6.2 years vs 6.1 ± 6.2 years; P < .01), more likely to present with cardiac arrest (43% vs 11%; P < .01), and less likely to be in the intensive care unit (40% vs 58%; P < .01) or on inotropes (30% vs 60%; P < .01) at the time of listing. Outcomes including waitlist mortality, transplantation, posttransplant survival, and freedom from rejection were comparable to those of the non-MA cohort. Conclusion: Patients with MA constitute a small proportion of those listed for HTX in childhood. CM was the most common category, while IA and PT were rare. Their waitlist mortality and posttransplant outcomes were comparable to those of the non-MA cohort.