A Single-Center Experience in Portal Flow Augmentation in Liver Transplantation With Prior Large Spontaneous Splenorenal Shunt

Hemodynamic alterations with large spontaneous splenorenal shunt ligation during adult deceased donor liver transplantation

Background

A large spontaneous splenorenal shunt (SRS) will greatly impact portal inflow to the graft during liver transplantation (LT). Direct ligation of a large SRS is an uncommon surgical procedure and the hemodynamic consequences of this procedure are unknown.

Methods

In this retrospective study, we described our technique for direct ligation of a large SRS and the consequent hemodynamic changes during LT. 3-Dimensional computed tomography and Doppler ultrasonography were used to evaluate SRS and portal vein blood flow volume (PFV).

Results

A total of 22 recipients had large SRS including 13 with PFV <85 ml/min/100 g (ligation group) and 9 with PFV ≥85 ml/min/100 g (no ligation group). The diameter of SRS was significantly larger in the ligation group than in the non-ligation group (22.92 ± 4.18 vs. 16.24 ± 3.60 mm; p = 0.0009). In all ligation patients, the SRS was easily identified and isolated, it was located just below the distal pancreas and beside the inferior mesenteric vein. PV flow increased significantly from 68.74 ± 8.77 to 116.80 ± 16.50 ml/min/100 g (p < 0.0001) after ligation; this was followed by a reduction in peak systolic velocity of the hepatic artery from 58.17 ± 14.87 to 46.67 ± 13.28 cm/s (p = 0.0013).

Conclusions

Direct ligation of large SRS was an effective and safe surgical procedure to overcome the problem of portal hypoperfusion during LT.

Management of spontaneous portosystemic shunts at the time of liver transplantation: treatment or observation? Results of a systematic review

BACKGROUND

Optimal treatment of spontaneous portosystemic shunts (SPSS) during liver transplantation (LT) remains debated. We systematically reviewed the literature on definitions, treatment and outcomes of patients presenting SPSS undergoing LT.

METHODS

According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we used PubMed to retrieve all studies dealing with SPSS and LT between January 1987 and January 2020. The primary endpoints were definitions and outcomes according to the management of SPSS (treatment vs observation).

RESULTS

Thirteen studies detailing the management of 962 SPSS were retrieved. Hemodynamically significant SPSS were defined as those having diameter ≥ 10 mm in 41% (n = 395) of patients. SPSS were splenorenal (42%), cavo-gastric (15.2%), umbilical (7.4%), mesenterico-caval (n = 31; 3.2%), mesenterico-renal (0.1%) and unreported (31.9%), respectively. At the time of LT 372 shunts (38.7%) were treated while 590 were observed (61.3%). During a follow-up time ranging from 4 months to 5 years, the reported overall survival (OS) at 1 year was not significantly different except for one study. Portal vein anastomosis complications (i.e. reduced flow, stenosis or thrombosis) were similarly reported in observed [n = 26 (4%)] and ligated SPSS [n = 10 (2%)] (p = 0.22) but the rate of relaparotomy was significantly higher in observed SPPS (16 vs 2; p = 0.01) to rescue post LT portal vein thrombosis (n = 6) and reduced portal flow and graft dysfunction (n = 10).

CONCLUSIONS

There was a heterogeneous management of SPSS during LT in the literature. Ligation of SPPS did not reduce vascular complications neither improved survival. A randomized prospective study might contribute to identify best management of SPSS at time of LT.

Validation of a standardized CT protocol for the evaluation of varices and porto-systemic shunts in cirrhotic patients

PURPOSE

The aim of the present study was to propose and validate a standardized CT protocol for evaluating all the types of portosystemic collaterals (P-SC), including gastroesophageal varices and spontaneous portosystemic shunts (SPSS), and to evaluate the prognostic role of portal hypertension CT features for the prediction of the hepatic decompensation risk in cirrhotic patients.

METHODS

A retrospective cohort study of 184 advanced chronic liver disease who underwent CT scan between January 2014 and December 2017. Patients with an interval > 6 months between the imaging, elastometric, endoscopic and biochemical evaluation were excluded, as well as patients with previous transjugular intrahepatic portosystemic shunt (TIPS), liver transplantation (LT) or terminal medical conditions. Data on liver disease history, co-morbidities, endoscopic and radiologic findings were collected. The incidence of hepatic decompensation and other events, such as portal vein thrombosis, HCC, TIPS placement, LT, death, and its cause, were also recorded. The procedure was performed at baseline and after the administration of contrast agent using a multiphasic technique and bolus tracking. Two senior radiologists working in different centres and a non-expert radiologist reviewed all CT examinations, to evaluate both intra-observer and inter-observer variability of the CT protocol and to obtain an external validation. The radiological variables were evaluated using both univariate and adjusted multivariate competing risk regression models.

RESULTS

Both intra-observer and inter-observer agreement were excellent in detection and measurement of almost all types of P-SC. The presence of SPSS, a spleen diameter > 16 cm, a portal vein diameter > 17 mm and the presence of ascites resulted independent predictors of decompensation-free survival for cirrhotic patients and were incorporated in an easy-to-use score (AUROC = 0.799, p-value = 0.732) which can the risk of decompensation at 5 years, ranking it as low (11.3%), moderate (35.6%) or high (70.8%).

CONCLUSIONS

The CT protocol commonly performed during the HCC surveillance program for cirrhotic patients is valid for detecting all types of P-SC. The radiological score identified to predict the decompensation-free survival for cirrhotic patients could be an easy-to-use clinical tool.

Renal Implications of Left Renal Vein Ligation for Portal Flow Augmentation in Liver Transplantation

BACKGROUND

Spontaneous lienorenal shunts (SLS) siphon blood away from the portal circulation and may compromise portal inflow in liver transplantation (LT). Performing a left renal vein ligation (LRVL) is a relatively easy and efficacious method of overcoming this portal 'steal'. However, given the delicate state of renal function in these patients, its short and long term effects remain undefined. The aim of this study was to evaluate the efficacy of LRVL in augmenting portal flow and safety with regards to renal function.

METHODS

A prospectively collected database of 1638 consecutive LT recipients between January 2010 and August 2020 was reviewed. Twenty-eight patients who underwent LRVL were identified. There were six paediatric recipients, who were analysed separately. Data with regards to imaging, renal function, intraoperative portal hemodynamics, and renal morbidity were analysed.

RESULTS

Of the 22 adults, 21 underwent live donor LT. 22.5% had a pre-transplant history of acute kidney injury (AKI). Pre-operative CT demonstrated portal vein thrombosis and SLS in 63.6% and 92.9% of patients respectively. LRVL resulted in a significant augmentation of portal hemodynamics in both the adult and paediatric recipients. Postoperatively, 14.3% and 35.7% of patients developed chylous drain output and AKI respectively. Of 13 patients who underwent CT at various timeframes, 5 patients had a partial re-canalisation of LRV at 6 months.

CONCLUSION

From renal and portal standpoints, LRVL is a safe and effective technique of augmenting portal inflow. Further large-scale multicentre studies and consensus will help define an objective algorithmic approach to LT recipients with SLS.