Introduction: Contrast-enhanced ultrasound (CEUS) is instrumental in evaluating the integrity of anastomosed hepatic arteries and portal veins, as well as identifying the presence of post-transplant bleeding. Notably, the arterial-portal arrival interval (APAI) has been linked to liver function abnormalities during the early post-transplantation period. This study aims to elucidate the relationship between APAI and the risk of significant portal vein stenosis, necessitating portal vein stenting (PVS), post liver transplantation.
Method: In this retrospective analysis, we examined 99 patients, including 33 who required PVS due to liver function test abnormalities or symptoms related to portal hypertension between March 2014 and June 2023. The remaining 66 patients did not exhibit portal vein stenosis. CEUS was conducted on all subjects on the first postoperative day, measuring the first-pass arrival times for both the hepatic artery (HAAT) and the portal vein (PVAT).
Results: A significant difference was observed in APAI between patients requiring PVS (4.3 seconds, standard deviation [SD] 2.1 seconds) and those who did not (2.1 seconds, SD 0.7) (p<0.001). Among the PVS group, 24 received grafts from living donors (72.7%), and strictures predominantly located at the main trunk level (30/33, 90.9%). Strictures at other levels were only noted in anastomoses performed using Y-shaped portal vein grafts. 18 patients underwent stenting within six months post-transplantation, with two (6.1%) requiring re-interventions—either angioplasty or re-stenting.
Conclusion: The first-pass APAI on CEUS is significantly associated with the development of critical strictures at the portal vein anastomosis following liver transplantation. These findings underscore the need for further research to validate these observations and to refine predictive models for post-transplantation portal vein complications.