Percutaneous Endovascular Stent Treatment of Hepatic Venous Outflow Obstruction After Pediatric Liver Transplantation

Background
Vascular complications following pediatric liver transplantation (LT) threaten graft function. Percutaneous endovascular rescue of allografts from hepatic venous outflow obstruction (HVOO) may be critical to optimizing outcomes.

Methods
Single-center series of pediatric LT recipients with HVOO Hemodynamic and angiographic assessment was followed by percutaneous stent implantation.

Results
Nine patients underwent percutaneous balloon-expandable stent treatment of HVOO at a median age of 2.9 yrs (range 1.3-16.1) and weight of 14 kg (10.3-46.7). The majority of patients (56%) had already undergone multiple venoplasty procedures. The median gradient before stent therapy was 4 mmHg (1-15) with dampening of the venous waveform and angiographic obstruction present in all cases. Stent placement was in the inferior vena cava (22%), hepatic vein (33%), or in both vessels (44%) with post-implantation stent modification performed to generate an unobstructed hepatic venous outflow in 4 patients (Figure 1). Acute relief of venous obstruction was demonstrated in all cases with median residual gradient of 0 mmHg (0-2), restoration of normal phasic HV waveform and angiographic flow, and clinical resolution of portal hypertension or decrease in serum transaminases. There were no procedural complications. At a median follow-up of 6.9 months (2-35), all patients remained free of recurrent clinical symptoms.

Conclusions
Percutaneous transcatheter stent therapy is safe and effective for relief of symptomatic HVOO following pediatric LT. The therapy remains durable at medium-term follow-up.