Amiodarone use prior to cardiac transplant in children is associated with increased need for post-transplant chronotropic support.

Background: The use of amiodarone prior to cardiac transplant in adults is associated with worse post-transplant outcomes. Data are scarce in pediatrics regarding the association of pre-amiodarone use with post-transplant outcomes. We aim to describe and compare pediatric post-transplant outcomes based on use of pre-transplant amiodarone at a large pediatric cardiac transplant center. Methods: We performed a retrospective cohort study of pediatric patients 18 years or younger who underwent cardiac transplant between 2015 - 2021. Pre-transplant amiodarone use was defined as use/administration of amiodarone within two weeks pre-transplant. Pre-transplant characteristics and post-transplant outcomes including mortality and markers of morbidity were compared between the two groups. Results: Six percent (10/156) of the study population were on amiodarone pre-transplant. There were no differences in mortality between the two groups. Severe primary graft dysfunction (PGD) incidence was higher in the pre-transplant amiodarone group (p = 0.04). The use of post-transplant isoproterenol (p = 0.01) and temporary pacing (p = 0.01) were higher in the pre-transplant amiodarone group. There was no association between either amiodarone dose or length therapy with post-transplant outcomes. Conclusions: Higher rates of PGD, increased use of isoproterenol, and need for temporary pacing post-transplant among patients receiving pre-transplant amiodarone suggests that amiodarone may contribute to inadequate chronotropy in the acute post-operative period. The need for chronotropic support occurred irrespective of amiodarone dose or length of therapy.