A recent study (AS Elnaggar et al. Liver Transplantation 2018; 24: 881-87; editorial 868-9) examine the effect of different types of surgical shunts in the setting of portal vein thrombosis (PVT). The authors examined surgical shunts from 1998-2011 in their institution (senior author: Jean Emond).
- 40 patients received “portal flow-preserving shunts”: 32 mesoportal and 8 selective splenorenal
- 24 received portal flow-diverting shunts (16 nonselective splenorenal and 8 mesocaval)
- Of these 64 patients, only 39 had preoperative and postoperative cross-sectional imaging. In addition, only 11 patients who had mesoportal shunt (7 children and 4 adults) had preoperative and postoperative cross-sectional imaging allowing for volume comparison.
Key finding:
- In patients receiving portal flow-preserving shunts (mainly mesoportal), this was associated with liver volume expansion (886 versus 1131 cm to the third), whereas diverting shunts were not.
The authors note that liver atrophy, especially in children, can have a “significant effect on cognitive function and somatic growth.” Thus, restoring portal flow may improve adverse effects that PVT has caused.
Limitations:
- Lack of validation of their formula to calculate liver volumes in the pediatric age group
- Relatively short follow-up:5.7 months in the portal-preserving group and 11 months in the other group
- Small numbers of patients..
Long-term followup of patients who have needed surgical shunts is needed. For mesoportal shunts, strictures have been noted in the hepatic end in 15% of patients.
My take: This study shows that portal blood flow, which was interrupted by PVT and restored by mesoportal (Rex) shunt, is important in maintaining liver mass. So, while all shunts may stop upper GI bleeding, mesoportal shunt is likely to improve other adverse effects of PVT.
