Portal Shunt Research Articles

Transcatheter local thrombolysis in patients with extensive TIPS thrombosis

Transcatheter local thrombolytic therapy in patients with portosplanchnic venous thrombosis has been used in few cases. Here, we present our single-center experience with transcatheter thrombolytic therapy in three patients with extensive refractory portal and transjugular intrahepatic portosystemic shunt (TIPS) thrombosis. Thrombolytic therapy was successful for all three patients. Two patients developed minor procedure-related bleeding. Local thrombolysis could be proposed in case of TIPS thrombosis for patients in whom the venous flow cannot be restored by using conventional anticoagulant therapy and stent mechanical revision.

Portal vascular anomalies in Down syndrome: spectrum of clinical presentation and management approach

Purpose The occurrence of portal vascular anomalies in Down syndrome has been sporadically reported in the literature. These rare disorders have a wide spectrum of anatomical and clinical presentations. The aim of this communication was to describe the clinical course, imaging features, and management approaches in patients with this association. Methods We conducted a comprehensive search of the databases of the Vascular Anomalies Center and the Department of Radiology at Children's Hospital Boston for patients with Down syndrome and portal vascular anomalies. Medical records and imaging studies of varying modalities were reviewed. Results Three children with Down syndrome and portal anomalies (portosystemic shunt, simple arterioportal shunt, complex arterioportal shunt) were managed at our institution. The portosystemic shunt was clinically insignificant and resolved without any intervention. The simple arterioportal shunt was successfully treated with embolization. The complex arterioportal shunt was associated with major congenital cardiac defects and the child ultimately expired despite a decrease in the arterioportal shunting after embolization. Conclusions Three is a wide spectrum of clinical and anatomical features of portal vascular shunts in Down syndrome. The management approach should be tailored based on the severity of symptoms. Percutaneous embolization can offer a safe, effective, and minimally invasive alternative to the surgical approach in selective cases.

Rat CCl4-induced cirrhosis plus total portal vein ligation: a new model for the study of hyperammonaemia and brain oedema

Animal models used to study hyperammonaemic disorders related to chronic liver disease are unsatisfactory. These animals only develop hyperammonaemia and brain oedema when fed with diets supplemented with amonium acetate. To develop a novel experimental model of hyperammonaemia and brain oedema in CCl(4)-induced cirrhosis in rats. Four groups were studied: rats with sham intervention (S), rats with total portal vein ligation (TPVL), cirrhotic rats (LC), and cirrhotic rats with TPVL (LC+TPVL). When ascites was diagnosed, oral glutamine challenge (OGC) test was performed. Blood, liver, lungs and brain samples were collected to quantify liver function parameters, plasmatic and cerebral ammonia, endotoxaemia, liver and brain histology, brain oedema and portosystemic shunting degree. LC+TPVL rats showed a significant increase in portosystemic shunting when compared with LC group and a significant derangement in liver function when compared with TPVL group. These alterations resulted in a significant increase in plasmatic and brain ammonia concentrations and a higher plasmatic endotoxaemia as compared with others. Similarly, the area under OGC curve was significantly increased in LC+TPVL group as compared with the others, and correlates with portal shunting. Low-grade brain oedema was only observed in LC+TPVL group. All cirrhotic groups showed liver regeneration nodules and type-II Alzheimer astrocytes LC+TPVL reproduce the main alterations - portosystemic shunting, plasmatic and cerebral hyperammonaemia and low-grade brain oedema - observed in cirrhotic patients with hepatic encephalopathy.

The retrospective study of transjugular intrahepatic portosystemic shunt with covered or uncovered stents in patients with portal hypertension

To retrospectively compare the clinical outcome in patients with portal hypertension treated with transjugular intrahepatic portosystemic shunt (TIPS) using Fluency stent-graft (PTFE-covered stents) or bare stents. Approval of study and treatment protocol and waiver of informed consent for the retrospective study were obtained from institutional review board. Informed consent was obtained from each patient before procedure. Sixty consecutive patients with portal hypertension treated with TIPS from April 2007 to April 2009 were included. TIPS creation was performed with Fluency stent-graft in 30 patients (group A) and with bare stents in 30 patients (group B). Liver function, TIPS patency and clinical outcome were evaluated every 3 months. During hospitalization, there was no hepatic encephalopathy and recurrency of variceal bleeding.Acute shunt occlusion was observed in one patient with group A and another patient with group B.Follow-up was performed with average time of (6.2 +/- 3.9) months in group A and (8.3 +/- 4.4) months in group B. The rates of recurrent bleeding, acute shunt occlusion, hepatic encephalopathy and death were 3.3% and 20.0%, 0 and 30.0%, 16.7% and 20.0%, 0 and 13.3% in group A and B. The rates of recurrent bleeding, acute shunt occlusion and death in group A was lower than those in group B. There was no difference of hepatic encephalopathy between group A and B. The decrease of portal pressure and portosystemic pressure gradient, and the increase of portal flow and shunt flow in group A were higher than those in group B. There were no difference of liver function, ammonia and MELD between group A and B. Fluency stent-graft is safe and effective in TIPS creation, with high patency rate. Covered-stent can improve the clinical outcome of portal hypertension.

Diagnosis of Cirrhotic Portal Hypertension and Compensatory Circulation Using Transsplenic Portal Scintigraphy with 99mTc-Phytate

Our objective was to investigate the diagnostic value and clinical significance of transsplenic portal scintigraphy in cirrhotic portal hypertension and compensatory circulation. Transsplenic portal scintigraphy, ultrasound, and gastroscopy were performed on 50 patients with cirrhotic portal hypertension and on 10 controls. According to the Child-Pugh classification, 15 patients with cirrhosis were Child A, 19 were Child B, and 16 were Child C. In the control group, the splenoportal vein was shaped like the letter S, and the portosystemic shunt index was 0.19 +/- 0.07. Portal hypertension portosystemic shunts were of 3 types: intrahepatic (13 patients; index, 0.52 +/- 0.19), compensatory (31 patients; index, 0.64 +/- 0.28); and completely extrahepatic (6 patients; index, 0.91 +/- 0.03). Collateral vessels were uphill, downhill, or complex. The portosystemic shunt index increased as cirrhosis and esophageal varices increased. There was statistical significance among groups (P < 0.05 or < 0.01). Transsplenic portal scintigraphy was sensitive for detecting the number and location of shunts and will allow for improved surgical planning.

A graft to body weight ratio less than 0.8 does not exclude adult-to-adult right-lobe living donor liver transplantation

Many centers require a minimal graft to body weight ratio (GBWR) >or= 0.8 as an arbitrary threshold to proceed with right-lobe living donor liver transplantation (RL-LDLT), and there is often hesitancy about transplanting lower volume living donor (LD) liver grafts into sicker patients. The data supporting this dogma, based on the early experience with RL-LDLT at Asian centers, are weak. To determine the effect of LD liver volume in the modern era, we investigated the impact of GBWR on the outcome of RL-LDLT with a GBWR as low as 0.6 at the University of Toronto. Between April 2000 and September 2008, 271 adult-to-adult RL-LDLT procedures and 614 deceased donor liver transplants were performed. Twenty-two living donor liver transplantation (LDLT) cases with a GBWR of 0.59 to 0.79 (group A) were compared with 249 LDLT cases with a GBWR >or= 0.8 (group B) and with 66 full-graft deceased donor liver transplants (group C), who were matched 3:1 according to donor and recipient age, Model for End-Stage Liver Disease score, and presence of hepatitis C and hepatocellular carcinoma with the low-GBWR group. Portal vein shunts were not used. Markers of reperfusion injury [aspartate aminotransferase (AST) and alanine aminotransferase (ALT)], graft function (international normalized ratio and bilirubin), complications graded by the Clavien score, and graft and patient survival were compared. As expected, LD recipients had a significantly shorter cold ischemia time (94 +/- 43 minutes for A, 96 +/- 57 minutes for B, and 453 +/- 152 minutes for C, P = 0.0001). However, the peak AST, peak ALT, absolute decrease in the international normalized ratio, day 7 bilirubin level, postoperative creatinine clearance, complication rate graded by the Clavien score, and median hospital stay were similar in all groups. The rate of biliary complications was higher with LD grafts than deceased donor grafts (19% for A versus 10% for B and 0% for C, P = 0.2). Patient survival was similar in all groups at 1, 3, and 5 years (91% for A versus 89% for B and 93% for C at 1 year, 87% for A versus 81% for B and 89% for C at 3 years, and 83% for A versus 81% for B and 87% for C at 5 years, P = 0.63). A Cox proportional regression analysis revealed only hepatitis C virus as a risk factor for poorer graft survival and not GBWR as a continuous or categorical variable. In conclusion, we found no evidence of inferior outcomes with smaller size grafts versus larger size LD grafts or full-size deceased donor grafts. Further studies are warranted to examine the factors affecting the function of smaller grafts for living liver donation and thereby define the safe lower limits for transplantation.

Orthotopic Liver Transplantation for Hepatic Adenoma in a Patient with Portal Vein Agenesis

Congenital portal vein agenesis, known as the Abernathy malformation, was first described in 1793. It is associated with focal nodular hyperplasia and adenomas due to abnormal hepatic regeneration secondary to abnormal or absent flow to the liver. We report a case of a 25-year-old Caucasian female with a complicated medical history including idiopathic membranoproliferative glomerulonephritis, hypertension, hyperlipidemia, Sweet's syndrome, acute febrile neutrophilic dermatosis, who incidentally was diagnosed with multiple liver nodules, the largest 14 cm in diameter, arising at the junction of the left and right hepatic lobes. She was also noted to have a congenital absence of the portal vein. There was no evidence of cirrhosis or portal hypertension. Liver function tests and  - fetoprotein were within normal limits. A biopsy of the largest mass revealed hepatocellular adenoma. Because of the size, location, and multiplicity of the lesions, we elected to proceed with orthotopic liver transplantation. She subsequently underwent deceased donor liver transplantation using the piggyback technique. Despite dividing the portal vein shunt after completion of the caval anastomosis and minimizing the portal vein clamp time, her spleen spontaneously ruptured, for which splenectomy was performed. The patient did well postoperatively with good liver function.

OP19.09: The importance of portal system evaluation and shunt dimensions in cases of agenesis of ductus venosus

OP19.09: The importance of portal system evaluation and shunt dimensions in cases of agenesis of ductus venosus

Hypergalactosemia in early infancy: Diagnostic strategy with an emphasis on imaging

Portosystemic shunt is one of the main causes of persistent hypergalactosemia without enzyme deficiency, but the diagnostic imaging strategy has not yet been established. The purpose of the present study was to establish a diagnostic imaging strategy. A retrospective investigation of the clinical and imaging findings of 10 children with persistent hypergalactosemia without enzyme deficiency detected by screening was undertaken. Abnormal ultrasonography (US) findings were detected in all eight patients with liver disorders. In three patients with citrin deficiency, the combination of fatty liver on US and laboratory evidence of cholestasis led to the diagnosis. In three patients with portosystemic shunt, US on sedation clearly depicted the shunt vessels. The extent was more easily understood on contrast computed tomography (CT). Per-rectal portal scintigraphy with N-isopropyl-p-I-123 iodoamphetamine and lung perfusion scintigraphy with (99m)Tc macroaggregated albumin were useful for evaluation of portal shunt index and assessment of pulmonary arteriovenous shunt. One patient underwent transarterial coil embolization. In two patients with hepatic tumor, the lesions and its vascularity were clearly demonstrated on US and dynamic CT. In one patient, small shunt index on per-rectal portal scintigraphy suggested no need for treatment. The other patient was treated with a combination of steroid, radiation, and interventional radiology. The etiology remained unknown in two children. In the assessment of hypergalactosemia, US is the modality of choice. CT is a useful tool for more detailed evaluation of the abnormalities found on US. Per-rectal portal scintigraphy and pulmonary perfusion scintigraphy play an important role in the evaluation of portosystemic shunt. Interventional radiology is sometimes effective.

Splenic-intrahepatic left portal shunt in an adult patient with extrahepatic portal vein obstruction without recurrence after pancreaticoduodenectomy

In the last decade, a superior mesenteric-intrahepatic left portal shunt (Rex shunt) has been reported for successful management of extrahepatic portal vein obstruction in children. However, in adults, a mesocaval shunt has been generally performed for the surgical management of extrahepatic portal vein obstruction because of the complexity of the underlying disease and the difficulty of the superior mesenteric-intrahepatic left portal shunt. We herein report an adult patient who was successfully treated by splenic-intrahepatic left portal shunt with an artificial graft (6-mm polytetrafluoroethylene) for complete obstruction of the extrahepatic portal vein following pancreaticoduodenectomy. The shunt procedure not only relieved portal hypertension but also restored hepatic portal flow. In the near future, the Rex shunt should be considered for a beneficial management of extrahepatic portal vein obstruction, even in adults.

Tezosentan, a novel endothelin receptor antagonist, markedly reduces rat hepatic ischemia and reperfusion injury in three different models

This study investigated the effects of dual endothelin (ET) receptor blockade in rat models of liver ischemia and reperfusion injury (IRI). Three models of IRI were used: (1) in vivo total hepatic warm ischemia with portal shunting for 60 minutes with control (saline) and treatment groups (15 mg/kg tezosentan intravenously prior to reperfusion), (2) ex vivo hepatic perfusion after 24 hours of cold storage in University of Wisconsin solution with control and treatment groups (10 mg/kg tezosentan in the perfusate), and (3) syngeneic liver transplantation (LT) after 24 hours of cold storage in University of Wisconsin solution with control and treatment groups (10 mg/kg tezosentan intravenously prior to reperfusion). Tezosentan treatment significantly improved serum transaminase and histology after IRI in all 3 models. This correlated with reduced vascular resistance, improved bile production, and an improved oxygen extraction ratio. Treatment led to a reduction in neutrophil infiltration and interleukin-1 beta and macrophage inflammatory protein 2 production. A reduction in endothelial cell injury as measured by purine nucleoside phosphorylase was seen. Survival after LT was significantly increased with tezosentan treatment (90% versus 50%). In conclusion, this is the first investigation to examine dual receptor ET blockade in 3 models of hepatic IRI and the first to use the parenterally administered agent tezosentan. The results demonstrate that in both warm and cold IRI tezosentan administration improves sinusoidal hemodynamics and is associated with improved tissue oxygenation and reduced endothelial cell damage. In addition, reduced tissue inflammation, injury, and leukocyte chemotactic signaling were seen. These results provide compelling data for the further investigation of the use of tezosentan in hepatic IRI.

Treatment of bile duct‐ligated rats with the nitric oxide synthase transcription enhancer AVE 9488 ameliorates portal hypertension

Nitric oxide levels are decreased in the cirrhotic liver and increased in the systemic vasculature. We investigated whether the nitric oxide synthase (NOS) transcription enhancer AVE 9488 ameliorates portal hypertension in cirrhotic rats. Rats with secondary biliary cirrhosis [bile duct ligation (BDL)] were treated with AVE 9488. BDL animals without treatment served as controls. Blood flow was determined with the microsphere technique. Intrahepatic resistance was measured by in situ perfusion. NOS-3 mRNA and protein levels in the liver, aorta and superior mesenteric artery (SMA) were measured. Arterial pressure did not differ between treated and non-treated animals. Portal pressure, hepatic portal-vascular resistance and perfusion pressure of the in situ perfused liver were lower in the AVE 9488-treated animals. Arterial splanchnic resistance, portal venous inflow and shunt volume were increased by AVE 9488. N (G)-nitro-l-arginine methyl ester abolished the effect of AVE 9488. AVE 9488-treated rats had higher liver NOS-3 mRNA and protein levels, whereas NOS-3 mRNA and protein in the aorta and the SMA did not vary between groups. Phosphorylation of liver vasodilator-stimulated phosphoprotein (VASP) and NOS-3 as well as hepatic nitrite/nitrate was increased by AVE 9488. Treatment of BDL rats with the NOS transcription enhancer AVE 9488 induces an increase in NOS-3 mRNA and protein in the liver. This is associated with an amelioration of portal hypertension.

Obliterative hepatocavopathy - ultrasound and cavography findings

Obliterative hepatocavopathy - ultrasound and cavography findingsBackgound. Obliterative hepatocavopathy is a relatively new term for the definition of primary inferior vena cava thrombosis and membranous obstruction of inferior vena cava that were included in Budd-Chiari syndrome.Case report. In this report, cavography and ultrasound findings of a case with a complete occlusion of inferior vena cava in a 36 year-old female patient who has been followed up with the diagnosis of hepatitis B related cirrhosis for 5 years were presented.Conclusions. Although this disease classically treated by surgery (e.g. portal or mesenteric-systemic shunting, liver transplantation), also interventional radiology procedures e.g. transjugular intrahepatic portosystemic shunting, percutaneous hepatic vein angioplasty and/or stent placement), now play an important role in the management4.

Staging of portal hypertension and portosystemic shunts using dynamic nuclear medicine investigations

To explore portal hypertension and portosystemic shunts and to stage chronic liver disease (CLD) based on the pathophysiology of portal hemodynamics. Per-rectal portal scintigraphy (PRPS) was performed on 312 patients with CLD and liver angioscintigraphy (LAS) on 231 of them. The control group included 25 healthy subjects. We developed a new model of PRPS interpretation by introducing two new parameters, the liver transit time (LTT) and the circulation time between right heart and liver (RHLT). LTT for each lobe was used to evaluate the early portal hypertension. RHLT is useful in cirrhosis to detect liver areas missing portal inflow. We calculated the classical per-rectal portal shunt index (PRSI) at PRPS and the hepatic perfusion index (HPI) at LAS. The normal LTT value was 24 +/- 1 s. Abnormal LTT had PPV = 100% for CLD. 27 non-cirrhotic patients had LTT increased up to 35 s (median 27 s). RHLT (42 +/- 1 s) was not related to liver disease. Cirrhosis could be excluded in all patients with PRSI < 5% (P < 0.01). PRSI > 30% had PPV = 100% for cirrhosis. Based on PRPS and LAS we propose the classification of CLD in 5 hemodynamic stages. Stage 0 is normal (LTT = 24 s, PRSI < 5%). In stage 1, LTT is increased, while PRSI remains normal. In stage 2, LTT is decreased between 16 s and 23 s, whereas PRSI is increased between 5% and 10%. In stage 3, PRSI is increased to 10%-30%, and LTT becomes undetectable by PRPS due to the portosystemic shunts. Stage 4 includes the patients with PRSI > 30%. RHLT and HPI were used to subtype stage 4. In our study stage 0 had NPV = 100% for CLD, stage 1 had PPV = 100% for non-cirrhotic CLD, stages 2 and 3 represented the transition from chronic hepatitis to cirrhosis, stage 4 had PPV = 100% for cirrhosis. LTT allows the detection of early portal hypertension and of opening of transhepatic shunts. PRSI is useful in CLD with extrahepatic portosystemic shunts. Our hemodynamic model stages the evolution of portal hypertension and portosystemic shunts. It may be of use in the selection of patients for interferon therapy.

Use of autogenous saphenous vein as a conduit for mesenterico-left portal vein bypass

The authors describe a case of extrahepatic portal vein (EHPV) thrombosis and portal hypertension treated with a variant of mesenterico-left portal vein bypass (MLPVB) or Rex shunt. In this case, a segment of autogenous greater saphenous vein was used to bridge the distance between the left gastric vein inflow and the left portal vein. Use of such nontraditional conduit in similar circumstances may expand the application of portal revascularization/decompression procedures in treating these patients.

Imaging Findings in Incidental Intrahepatic Portal Venous Shunts

The purpose of our study was to describe the imaging findings in incidentally discovered intrahepatic portal venous shunts. Intrahepatic portal venous shunts are uncommon hepatic vascular anomalies that are often not associated with manifestations of liver disease or symptoms. They are most often solitary and in the left hepatic lobe. Identification of 25 intrahepatic portal venous shunts at a single institution over 6 years suggests that they may be more common than previously known and that with an increasing use of imaging, they may be identified more often in the future.

Troubles de la perfusion hépatique secondaires à une thrombose cave supérieure : à propos de trois cas

The aim of this study was to evaluate the altered flow dynamics of liver perfusion that can be observed during superior vena cava obstruction. Through the description of three case reports of patients with SVC obstruction, the authors discuss the different collateral pathways used that result in systemic portal venous shunting creating this altered flow dynamics and their appearance in computed tomography.

THREE‐DIMENSIONAL MULTISLICE HELICAL COMPUTED TOMOGRAPHY TECHNIQUES FOR CANINE EXTRA‐HEPATIC PORTOSYSTEMIC SHUNT ASSESSMENT

The purpose of the present study was to investigate the feasibility and usefulness of three-dimensional (3D) multislice computed tomography (CT) angiography with maximum intensity projection (MIP) and volume rendering (VR) in six dogs with clinical and sonographic findings suggestive of portosystemic shunt. Furthermore, we aimed to estimate the diameter of the portal vein and shunt vessels. MIP and VR reconstructions were performed for each patient and the origin and insertion of all shunt vessels were detected. In addition, 3D reconstructions allowed excellent depiction of vascular morphology and topography. All diagnoses and vessel measurements were confirmed by surgery. 3D multidetector CT angiography is a promising, noninvasive, and accurate method of evaluating dogs with suspected portosystemic shunts.

A Technical Tip for Creation of a Drapanas Mesocaval Shunt

The goal of a portal shunt is portal decompression. Meso-caval shunts are advised for patients with portal vein thrombosis or when the possibility of future liver transplantation favours avoidance of a right upper quadrant shunt.1 Meso-caval shunt technique consists of division of the inferior vena cava (Clatworthy) and anastomosis side to end with the superior mesenteric vein. An alternative simplified technical approach to meso-caval shunt is the interposition shunt of Drapanas, in which a graft between the inferior vena cava and the superior mesenteric vein at the level of its first branches is accomplished.

The fetal circulation and essential organs—a new twist to an old tale

The fetal circulation and essential organs—a new twist to an old tale