Early Post-Operative Versus Late Arrhythmias After Heart Transplant at a Pediatric Center: Incidence, Management, and...

Arrhythmias in pediatric heart transplant patients have historically raised concerns for acute rejection, often prompting invasive evaluation and empiric treatment. Despite this, the association of post-transplant arrhythmias with adverse outcomes remains understudied.

This is a retrospective single center review of pediatric patients who underwent heart transplant between 01/2014 and 12/2022. Arrhythmias were classified as early ( 14 days post-transplant) and as atrial, ventricular, or bradyarrhythmias. Adverse outcomes including death, re-transplantation, acute cellular rejection, acute antibody-mediated rejection, and cardiac allograft vasculopathy were compared by chi-squared or Fisher Exact test for those with and without arrhythmias.

Among 184 patients, 116 (63%) had at least 1 arrhythmia (284 total arrhythmia episodes). Overall, 99 (35%) arrhythmia episodes occurred in the early post-operative period and 137 (48%) arrhythmia episodes were ventricular. Anti-arrhythmic therapy was started for 69 (24%) arrhythmia events. There were 42 biopsies prompted by arrhythmia, yielding a new diagnosis of acute cellular rejection in 2 (5%) patients and antibody mediated rejection in 1 (2%) patient. No biopsies prompted by arrhythmia in the early post-transplant period were positive for rejection. Compared to those without arrhythmia, patients with at least one arrhythmia episode were not at increased risk of cardiac allograft vasculopathy, any post-transplant rejection, retransplantation, or death (p = 0.26-0.78).

Post-transplant arrhythmias occur commonly in pediatric heart transplant patients but are not clearly associated with rejection or adverse outcomes. Further study in larger patient populations is necessary to better understand the significance of post-transplant arrhythmias.