Heart Transplant Outcomes in Children with Ebstein's Anomaly

Abstract

Large variability exists in the medical and surgical management strategies for patients with Ebstein's anomaly (EA). However, in severe cases, options may be limited to heart transplantation (HT). Despite this, little data regarding outcomes of HT in EA patients exist to guide decision-making in this population. We report outcomes following HT in children with EA and describe characteristics associated with a poor HT outcome in the EA population. The Scientific Registry of Transplant Recipients and Pediatric Health Information System databases were linked at the patient level using indirect identifiers (2002 - 2016). Pediatric HT recipients with a diagnosis of congenital heart disease (CHD) were included, and those with a diagnosis of EA were identified using pre-HT ICD9/10 codes. The log-rank test was used to compare graft survival in HT recipients with EA and those with other forms of CHD. Post-HT morbidities including extracorporeal membrane oxygenation (ECMO), dialysis, stroke and rejection were also compared between groups. Cox regression was used to analyze factors associated with graft loss in the EA population. A sub-analysis of EA patients listed for HT at age ≤6 months was performed to determine if survival in this population differed from older EA patients following HT. A total of 1453 patients were identified for inclusion and 58 (4%) had EA. Of the EA patients 26 (44.8%) were male, median age at HT was 4 years (IQR 0-11 years), and 6 (10.3%) had undergone prior cardiac surgery. Support at the time of transplant for the EA group included mechanical ventilation (n=45, 77.6%), ECMO (n=6, 10.3%) and ventricular assist device (n=4, 6.9%). There was no difference in 5-year graft survival following HT in patients with EA vs other forms of CHD (76% vs 73%, p=0.84). Pre-HT ECMO was associated with graft loss in the EA population (HR 3.6, 95%CI 1.1-11.3). Between EA and CHD groups, no difference was detected in post-HT morbidities including ECMO (5.2% vs 9.1%, p=0.3), dialysis (8.6% vs 7%, p=0.64), stroke (0% vs 3.8%, p=0.13), or rejection (8.2% vs 17%, p=0.1). Sub-analysis of 19 (32.7%) EA patients listed for HT at ≤6 months of age showed no difference in 5-year survival compared to older patients with EA (83% vs 74%, p=0.88). Children with EA have similar outcomes after HT when compared with all types of CHD. Therefore, HT should remain a consideration if otherwise indicated in this population.