Cardiac allograft vasculopathy in pediatric heart transplant recipients does early-onset portend a worse prognosis?

Purpose: We sought to evaluate the association between timing of cardiac allograft vasculopathy (CAV) occurrence post-heart transplant (HT) with graft survival and progression of CAV severity in pediatric HT recipients.

Methods: Data from the Pediatric Heart Transplant Society for pediatric (<18 years old) HT recipients between 1993-2019 with available angiographic data were obtained (N = 5,075). The timing of CAV diagnosis (<3; 3-<5; 5-<10; and ≥10 years post-HT) and severity of disease at each assessment (CAV 1-3) was determined. Associations between CAV timing, graft survival, and CAV progression were evaluated using Kaplan-Meier survival curves, multivariable COX proportional hazard regression analyses, and competing risk analyses.

Results: Over a median follow-up period of 4.1 (IQR 1.3-8.3) years, CAV was identified in 17% (885/5,075), 28% (252/885) of which were early-onset CAV. Compared with late onset CAV ≥10 years post-HT, patients with early CAV were older at the time of transplant (8.3 ± 6.2 vs. 3.8 ± 4.8 years, p < .0001). While the five-year graft-survival in the ≥10-year group (79.2%, p = 0.03) was significantly higher than the <3, 3-<5, and 5-<10 years post-HT groups (65.0%-67%) (p = 0.03), overall post-CAV graft survival was not significantly different across the CAV time-points. CAV disease progression did not vary with CAV timing post-HT, with an overall five-year freedom from CAV ≥2 of 75.4% (73.1%-77.6%).

Conclusion: Later onset CAV (≥10-years post-HT) was associated with improved five-year graft survival compared with CAV onset at earlier time-points, but similar and poor long-term outcomes. CAV timing post-HT was not associated with progression of CAV disease severity.