Cardiac Allograft Vasculopathy in Pediatric Heart Transplant Recipients: Does Early Onset Portend a Worse Prognosis?

Abstract

<h3>Purpose</h3> We sought to evaluate the association between early-onset cardiac allograft vasculopathy (CAV) [<3 years post heart transplant (HT)] & graft survival (freedom from death & re-transplantation), compared with CAV development at later time-points in pediatric HT recipients. <h3>Methods</h3> Data from the Pediatric Heart Transplant Society (PHTS) for pediatric (<18 years old) HT recipients between 1993-2019 with available angiographic data were obtained (N = 5,075). Patients with a diagnosis of CAV were categorized according to the timing of disease post-HT; <3 years; 3-<5 years; 5-<10 years; & ≥10 years. CAV severity was graded at each assessment (CAV 1-3). Kaplan-Meier survival curves were generated to evaluate the association between CAV timing & graft survival (primary outcome). A competing risk analysis was used to evaluate the association between CAV timing & the progression of CAV severity (secondary outcome). <h3>Results</h3> Over a median follow-up period of 4.1 (IQR 1.3 - 8.3) years, angiographic evidence of CAV was identified in 17% (885/5,075) of patients, 28% (252/885) of which were early-onset CAV. Compared to those who developed CAV >10 years post HT, patients with early-onset CAV were older at transplant (8.3 +/- 6.2 vs. 3.8 +/- 4.8 years, p < .0001). Five-year graft survival following CAV diagnosis at any time point was 68.7% (66.8% - 70.4%). Graft survival post-CAV diagnosis was not significantly different for early-onset CAV compared with CAV at later time points (Figure). For patients with CAV-1, freedom from progression to CAV-2 did not vary according to the timing of CAV onset, with an overall five-year freedom from CAV-2 of 75.4% (73.1%-77.6%). <h3>Conclusion</h3> Following diagnosis, the progression of CAV & graft survival was similar for patients with early-onset CAV compared with CAV at other time points. These findings suggest that early-onset CAV does not necessarily represent a more aggressive phenotype of disease.