Abstract 17386: Pulmonary Vein Stenosis After Pediatric Heart Transplant

Introduction: Pulmonary vein stenosis (PVS) is a rare condition in which neointimal proliferation of the pulmonary veins leads to venous and arterial hypertension. Little is known about the development of PVS after heart transplant (HTx) in children, which is a rare but known complication of HTx.

Research Question: To describe the clinical characteristics, progression of disease, and outcomes of children who develop PVS after HTx.

Methods: We performed a retrospective review of patients ≤18 years old who underwent HTx at two pediatric centers, Children’s Healthcare of Atlanta and Lurie Children’s Hospital, between April 2012-April 2022. Patients with a diagnosis of PVS were identified through queries of PVS databases at each center. Details related to the underlying cardiac diagnosis, location and extent of PVS, and post-HTx outcomes were recorded.

Results: During the study period, 374 patients underwent HTx across both centers. Seventeen PVS patients (9 male) were identified, 15 of whom had de novo PVS. Fifteen had underlying congenital heart disease (CHD) and 2 had cardiomyopathy. Among CHD patients, 2 had a history of anomalous pulmonary venous return and 14 had prior cardiac surgery. Two patients had undergone catheter based PVS intervention prior to Tx. PVS was diagnosed at a median of 2 months (range 2 weeks-14 years) after HTx. At initial diagnosis, 12 patients had one-vessel PVS, most commonly the left upper pulmonary vein (n=8). At final follow-up, 2 patients had 2-vessel PVS and 7 had 3-4 vessels involved. Surgical intervention was required in 8 unique patients, most commonly for the left veins. Stent or balloon angioplasty were used in all left-sided veins, most commonly in the left lower pulmonary vein (n=8). Two patients were medically treated for pulmonary hypertension following PVS diagnosis. There were 3 deaths in the cohort, 2 of which were thought to be caused by right heart failure secondary to PVS.

Conclusions: This is the first study to describe the characteristics of post-HTx PVS in children. PVS occurs in 4.5% of HTx and history of CHD is a strong risk factor. Multiple vessels can be involved and may require catheter-based or surgical intervention. Clinicians must be vigilant in monitoring for the development of PVS in this population.