Long-term venous complications after full-size and segmental pediatric liver transplantation

Abstract

Objective: To assess the long-term incidence of venous complications, including portal vein and hepatic vein stenoses, in both whole cadaveric and reduced-size cadaveric and living related liver transplants in a pediatric population, and to assess the therapeutic modalities in the treatment of these lesions.

Summary background data: A shortage in appropriate-sized liver grafts for pediatric patients led to the use of segmental liver grafts, which became the predominant graft used in 325 of 600 (54%) transplants at the authors' institution. To assess the long-term impact of this strategy, the authors examined the incidence of late (>90 days) venous complications and the efficacy of all therapeutic interventions.

Methods: Six hundred pediatric liver transplants were performed in 325 patients, with reduced-size or split (RSS; n = 207), living related (LRD; n = 118), or full-size cadaveric grafts (FS; n = 275) from 1988 to 2000. All transplants identified with late portal vein or vena caval stenoses or thromboses from a cohort of 524 grafts with survival greater than 90 days were reviewed for demographics, symptoms, therapeutic intervention, recurrence, morbidity, and mortality.

Results: Fifty lesions were identified in 49 patients (38 portal vein and 12 hepatic vein-cava stenoses). Sex distribution was similar between portal vein and hepatic vein to cava, as was the mean patient age. Portal vein stenoses occurred in 32 LRD, 3 RSS, and 3 FS, while hepatic vein-cava stenoses occurred in 2 LRD, 8 RSS, and 2 FS. In the 38 portal vein stenoses, 9 had prior perioperative portal vein and/or 5 hepatic artery thrombectomies. Portal vein stenoses were identified after bleeding (17/38), ascites (6/38), increased liver function tests (6/38), splenomegaly (5/38), or screening ultrasound (4/38). Portal vein stenosis was associated most often with cryopreserved vein for portal conduits. Excluding conduits, the incidence of late portal vein complications was reduced to 1%. Lesions became symptomatic at a mean of 50.8 +/- 184.2 months posttransplant. All patients underwent venous angioplasty with a 66% (25/38) success rate, while 7 of 25 required further angioplasty and stenting. In the 13 unsuccessful angioplasties, 8 required surgical shunts for complete portal vein thrombosis. Recurrence occurred in 9 patients: all were amenable to stenting. Nine patients (24%) eventually died of sepsis (4) and surgical deaths at shunt or retransplant (5). Hepatic vein-cava stenoses occurred after a mean of 37.2 +/- 35.2 months, presenting with ascites (n = 10), increased liver function tests (n = 2), and splenomegaly (n = 2). All patients were diagnosed by venogram and managed by balloon dilatation alone (n = 6) or stented (n = 4), with an 80% (10/12) success, with two late recurrences amenable to repeat angioplasty or stenting. Long-term survival was 80% at 1 year.

Conclusions: The use of segmental grafts without venous conduits is not associated with a significant rate of long-term venous complication. When late venous complications do occur, venous angioplasty and stenting are both a safe and effective management modality. If necessary, venous angioplasty may be repeated with the placement of a stent. When this is required, care must be taken to place the stent in a position where the metallic object will not interfere with future surgical manipulations should retransplantation be necessary.

Figure 1. Incidence of long-term portal vein and hepatic vein stenosis divided by era, comparing 1988 to 1994 and 1995 to present.

Figure 2. Portal venous stenosis demonstrated by venogram obtained with contrast injection into the extrahepatic portal vein after percutaneous puncture. (A) Fluoroscopic image demonstrating venoplasty of stenotic segment. (B) Site of recurrent stenosis requiring stenting. (C) Placement of endovascular stent at stenotic point (D).

Figure 3. Patient survival graph with respect to successful and unsuccessful balloon angioplasty or stenting for late portal vein stenoses.

Figure 4. Hepatic vein stenosis demonstrated by venogram obtained with contrast injection into the inferior vena cava after a percutaneous femoral puncture. (A) Fluoroscopic image demonstrating venoplasty of stenotic segment. (B) Site of recurrent stenosis requiring stenting. (C) Placement of endovascular stent at stenotic point (D).

Figure 5. Patient survival graph with respect to successful and unsuccessful balloon angioplasty or stenting for late hepatic vein stenoses.