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PubMed1991

Portal-systemic encephalopathy: presence of basal ganglia lesions with high signal intensity on MR images.

Sixteen patients with cirrhosis of the liver underwent cranial magnetic resonance (MR) imaging and transarterial portography to evaluate the relationship between basal ganglia lesions and portal-systemic collateral vessels. No neuropsychiatric disturbance was observed in any of the patients at the time of the MR examination, but four patients with portal-systemic encephalopathy were included in the study. Basal ganglia lesions, characterized by increased signal intensity on T1-weighted MR images, were observed in nine of the 16 patients, including the four with portal-systemic encephalopathy. These nine patients had large portal-systemic collateral vessels that were more than 10 mm in diameter. These collateral vessels were receiving blood from the superior mesenteric vein (SMV) in all nine patients. The lesions involved the globus pallidus and portions of internal capsules in a bilateral and symmetric fashion and did not exhibit mass effect. The authors conclude that there may be a significant relationship between high-intensity basal ganglia lesions and large portal-systemic collateral vessels receiving blood from the SMV.

Aged↗
PubMed2006

Evaluation of paraumbilical vein as a prognostic index of severe liver cirrhotic patients with portal-systemic shunts.

AIM: The aim of this study was to predict the outcome in severe liver cirrhotic patients with portal-systemic shunts. METHODS: One-hundred and sixteen patients with liver cirrhosis diagnosed as Child-Pugh class B and C with portal-systemic shunts confirmed by abdominal ultrasonography, computed tomography and magnetic resonance imaging were enrolled in this study. Twenty-three factors were evaluated concerning clinical laboratory parameters and extracted prognostic factors using the Cox proportional hazards model, and the prognostic index (PI) was prepared by combining these factors. RESULTS: The cumulative survival rates after admission were 64.6%, 35.6% and 25% after 1, 3 and 5 years, respectively. Using multivariate analysis, age, the presence of hepatocellular carcinoma (HCC), portal vein tumor thrombosis (PVTT) and paraumbilical vein (PUV) shunt were selected as significant prognostic factors that contributed independently to the prognosis of severe liver cirrhotic patients with portal-systemic shunts. The PI was calculated with the following formula using these 4 factors. PI = 0.042 x Age + 0.913 x HCC + 0.989 x PVTT + 1.079 x PUV shunt. The group with a high score for PI was found to die with significantly higher frequency than the group with a low score. CONCLUSIONS: It was found that tumor related factors and PUV shunt were the most important factors for severe liver cirrhotic patients with portal-systemic shunts. The PI is suggested to be an appropriate index to predict the prognosis for these patients.

Aged↗
PubMed1987

Quantitative aspects of portal-systemic and arteriovenous shunts within the liver in cirrhosis.

To estimate vascular changes in chronic liver disease, we quantitated intrahepatic arteriovenous and portal-systemic shunts in 12 patients with cirrhosis and arteriovenous shunts alone in 4 patients with cirrhosis. An index was obtained for intrahepatic arteriovenous shunts by instilling technetium 99m-macroaggregated albumin into the proper hepatic artery and portal-systemic shunts, by the same procedure done in the portal trunk, near the porta hepatis on different days. Counts were taken over the liver and both lungs in the anterior as well as the posterior view for calculation of the shunt index: cpm in lungs divided by cpm in liver and lungs X 100%. In the 12 patients with cirrhosis in whom both shunts were measured, intrahepatic arteriovenous shunting was significantly lower compared with intrahepatic portal-systemic shunting (1.4% +/- 1.1% vs. 36.0% +/- 29.0%, p less than 0.001). Thus, it seems that in patients with cirrhosis, the development of intrahepatic arteriovenous shunts is not as great as that of portal-systemic shunts, which were found in this study to be considerable and variable in degree.

Adult↗
PubMed2000

Caval inflow to the graft: a successful way to overcome diffuse portal system thrombosis in liver transplantation.

Portal vein thrombosis was considered to be a major contraindication to liver transplantation before the introduction of vessel grafts from the recipient's area of confluence of the splenic and superior mesenteric veins, behind the neck of the pancreas, to the graft's portal vein. Refinement in surgical technique has given rise to a large number of possibilities to overcome portal vein thrombosis in OLT recipients, ranging from portal vein thrombectomy to several different venous graft jump reconstructions. All these reconstructions require the presence of a patent vein of the portal system. When neither splanchnic veins nor sufficiently large venous collaterals are available, liver transplantation has been considered impossible. Salvage solutions include arterialization of the portal vein with the associated risk of liver damage in the longterm, a combined liver and bowel transplantation has been proposed but not yet reported (and in any case the results of combined liver and bowel transplants are not as good as those of liver transplantation alone) and finally the use of blood inflow from the inferior vena cava as first reported by Tzakis and coworkers. Portal flow from the inferior vena cava may be performed as a last resort. Although the consequences of severe pretransplantation portal hypertension remain and should be treated before, during, and after transplantation, liver function is normal in the short and midterm. With this new procedure, diffuse portal vein thrombosis is no longer an absolute contraindication to liver transplantation. But this needs to be confirmed in light of further experience and longterm followup.

Anastomosis, Surgical↗
PubMed1978

Motor nerve conduction velocity in experimental portal-systemic shunting. Preliminary communication.

The influence of portal-systemic shunting on motor nerve conduction velocity (MCV) was analyzed in rats with portacaval shunts. At 3 and 8 weeks after the shunting there was a marked but transient fall in MCV. At 16 weeks the MCV had almost normalized, despite sustained portal-systemic shunting. The results favour hepatocellular failure as the more important pathophysiological mechanism in hepatic neuropathy.

Animals↗
PubMed2001

Therapeutic effect of balloon-occluded retrograde transvenous obliteration on portal-systemic encephalopathy in patients with liver cirrhosis.

OBJECTIVE: Balloon-occluded retrograde transvenous obliteration (B-RTO) has recently been introduced as a new interventional modality to prevent fatal bleeding from solitary gastric varices. A large portal-systemic shunt including gastric varices also causes severe encephalopathy in some cirrhotic patients. In this study, we evaluated the effect of B-RTO as a candidate therapeutic method to treat chronic recurrent hepatic encephalopathy due mainly to a portal-systemic shunt. PATIENTS AND METHODS: Since July 1995, we experienced 43 cirrhotic patients with chronic reccurent hepatic encephalopathy. Among them, six patients had anigographically proven large (>1 cm in diameter) portal-systemic shunt, and received B-RTO. B-RTO was carried out only once using 5% ethanolamine oleate with iopamidole to obliterate the portal-systemic shunt for 30 minutes. The median observation period after B-RTO was 29 months (range 23-46 months). RESULTS: In all 6 patients, encephalopathy had disappeared after B-RTO, and the patients were free of encephalopathy during the following 6 months. B-RTO significantly reduced blood ammonia levels at one month, 3 months, and 6 months later, without affecting serum aspartate aminotransferase activity, total bilirubin and albumin concentrations, and plasma prothrombin time. Encephalopathy relapsed in 4 patients between 6 and 30 months. Additional B-RTO was required and effective in 2 of them. CONCLUSION: B-RTO is an effective treatment for chronic recurrent hepatic encephalopathy with an angiographically proven portal-systemic shunt.

Aged↗
PubMed1980

The use of ornithine salts of branched-chain ketoacids in portal-systemic encephalopathy.

In eight patients with chronic portal-systemic encephalopathy who were symptomatic despite protein restriction and lactulose, a double-blind crossover comparison was conducted of branched-chain amino acids (68 mmol/d) versus ornithine salts of branched-chain ketoacids (34 mmol/d), both mixtures being administered orally for 7 to 10 days, after control periods, during a single hospitalization. Ornithine salts of branched-chain ketoacids markedly improved electroencephalographic abnormalities and clinical grade of encephalopathy; branched-chain amino acids had significantly lesser effects, which were of borderline statistical significance. To ascertain whether ornithine or branched-chain ketoacids were responsible for the improvement observed, we administered to six patients calcium salts of branched-chain ketoacids (34 mmol/d) after control periods; only slight improvement was seen.. Four patients received a daily dose of ornithine alpha-ketoglutarate containing the same quantity of ornithine; one did not change and three deteriorated rapidly. We conclude that the combination of ornithine and branched-chain ketoacids improves chronic portal-systemic encephalopathy more than its components given separately and more than branched-chain amino acids at twice the molar dose.

Adult↗
PubMed1991

Contribution of portal systemic shunt to Kupffer cell dysfunction in obstructive jaundice.

Previous animal models of biliary tract obstruction have shown that hepatic phagocytic activity is impaired secondary to Kupffer cell dysfunction. Biliary tract obstruction leads to portal hypertension and an associated portal systemic shunt. Forty-eight Sprague-Dawley rats were studied to determine the contribution of portal systemic shunt to Kupffer cell dysfunction after 21 days of obstructive jaundice or sham operation. Liver uptake of radiolabeled Escherichia coli decreased from 76.1 +/- 1.4% (sham) to 63.1 +/- 6.1% in the common duct ligation (CDL) rats (P less than 0.05); lung uptake increased from 4.0 +/- 0.6% (sham) to 20.2 +/- 4.5 (CDL) (P less than 0.05). Portal systemic shunt, determined using radioactive microspheres, increased from 2.0 +/- 1.0% (sham) to 46.6 +/- 13.1% (CDL), P less than 0.05. Although a significant portal systemic shunt does exist in this 21-day model of obstructive jaundice, it does not appear to be the only mechanism underlying Kupffer cell dysfunction.

Animals↗
PubMed1996

Determination of functional portal-systemic shunting in patients submitted to hepatic angiography.

Angiographic visualization of the hepatic vascular bed by selective angiography can be profitably complemented with the evaluation of functional portal-systemic shunting by D-sorbitol bioavailability. Seventeen patients requiring diagnostic arterial catheterization were studied: most of them had biopsy-proven liver cirrhosis. Patients were studied at rest and after overnight fasting on two subsequent days, in which a sterile pyrogen-free solution (1.5%) of D-sorbitol was administered by direct infusion (15 mg/min for 20 min) into the superior mesenteric artery and an antecubital vein, respectively. The fractional bioavailability (Fma) of D-sorbitol was calculated as the ratio between the net cumulative urinary outputs obtained after infusion through the catheter into the superior mesenteric artery and the systemic vein, respectively. A good correlation was found between the estimated fractional portal-systemic shunting, which in the present study ranged between 1.4% and 96.7%, and a suitable index scoring the clinical evidence of collateral circulation. Since the hepatic removal of D-sorbitol is not affected by sinusoidal capillarization and its hepatic extraction ratio is quite high and only slightly modified by reduction in the number or functional activity of hepatocytes, the measured Fma can be assumed as a parameter reflecting the entity of portal-systemic shunting. The test is safe and inexpensive, and appears potentially useful in several situations in which portal-systemic shunting is pathophysiologically relevant.

Adult↗
PubMed1975

Flow and pressure characteristics of the portal system before and after splenorenal shunts.

The technique of percutaneous transhepatic portal vein cannulation provides a valuable means for determining portal pressure, direction of blood flow, and visualization of the entire portal system in the nonanesthetized patient. This technique, along with selective celiac arterial, superior mesenteric arterial, and renal venous catheterization, was used in the evaluation of a series of 17 splenorenal venous shunts [eight nonselective and nine selective (modified) distal splenorenal shunts]. As a result of these studies it is concluded that (1) prograde portal flow is maintained in the majority of patients following nonselective or selective (modified) distal splenorenal shunts; (2) bidirectional flow occurs in various branches of the portal system before and after splenorenal shunts; (3) a significant drop in portal pressure occurs following the establishment of either type of shunt; and (4) esophageal varices are decompressed by the trans-splenic route following either type of procedure used in this study.

Blood Pressure Determination↗
PubMed1984

Neuropsychiatric sequelae of portal-systemic encephalopathy: a review.

Portal-systemic encephalopathy (PSE) is a common condition affecting individuals with chronic hepatic dysfunction. The clinical presentation of PSE often mimics a number of psychiatric disorders and, as discussed in the text, complicates the treatment of persons who suffer from both liver dysfunction and psychiatric illness. This review of the literature addresses the etiology, natural history and treatment of PSE. Special attention is devoted to clarifying the cognitive and affective manifestations of chronic low grade PSE.

Affective Symptoms↗
PubMedDate not supplied

[The portal system (vena portae). Embryology and morphology (author's transl)].

The embryology and anatomy of the portal system are reviewed in the light of data reported in the published literature. A detailed description of the mode of formation of the portal vein and its branches up to the 52nd day of intrauterine life is given, this being the period when embryonic features are comparable to those in adults. Dimensions and physiological variations during growth are discussed, though it is regrettable that few studies have been concerned with this aspect. Portal system afferent vessels are then described and several statistics cited, this providing an explanation for the different modes of origin of the main portal vessel, and the limits of the regions not receiving collaterals. These anatomical zones, isolated in this manner, represent elective zones for surgical approach and for anastomotic procedures.

Adolescent↗
PubMed1983

Portal-systemic spill-over of bile acids: a study of mechanisms using ursodeoxycholic acid.

Portal-systemic spill-over of unconjugated ursodeoxycholic acid (UDCA) was assessed in ten healthy subjects, six patients with mild chronic liver disease and eight patients with cirrhosis. Following oral administration of UDCA (1.5 mg/kg body weight), serum concentrations of unconjugated UDCA were measured during 2 h using a capillary gas-liquid chromatographic method. Peak time of UDCA varied from 15 to 30 min, but was not significantly different in the three groups studied. Peak concentration was increased up to two-fold in patients with mild, and up to three-fold in patients with cirrhotic liver disease. Since, in addition, plasma disappearance rate (k) was markedly impaired in cirrhotics (1.7 +/- SD 0.5%/min, compared to 2.8 +/- 0.6 in healthy controls), the calculated area under the curve (AUC) was on the average five-fold that in controls. In two healthy and four cirrhotic subjects, the data obtained after oral administration were compared with those after i.v. loading with the same UDCA dose. The k-values after the two routes of administration were practically identical. Calculated systemic availability was 50% in normals, 78-87% in cirrhotics, 90 and 136% in two patients with surgical porta-caval shunt. It is concluded that the portal-systemic spill-over of UDCA in patients with liver disease is increased primarily due to portal-systemic shunting. Since in the normal liver hepatic extraction of conjugated, endogenous bile acids is greater than 80%, diminished first-pass elimination is expected to augment systemic concentrations even more, particularly when measured after a meal.

Adult↗
PubMed1998

Psychiatric aspects of portal-systemic encephalopathy.

This paper focuses on psychiatric aspects of portal-systemic encephalopathy (PSE) due to chronic liver disease and/or portal-systemic shunting. Clinical syndromes of PSE are discussed from the point of view of biological psychiatry, but, psychological consequences of concomitant cognitive disorders are also addressed. Psychiatric symptoms of early PSE and sleep disorders in patients with chronic liver disease are of specific interest.

Affect↗
PubMed1986

A new therapy for portal systemic encephalopathy.

This report describes a new therapeutic approach to the treatment of adults with portal systemic encephalopathy using sodium benzoate and sodium phenylacetate, two compounds that increase conjugated nitrogen excretion in the urine and that have been shown to be an effective treatment for children with congenital hyperammonemia. The study was a double-blind cross-over study in which each patient was his own control. All patients either improved their mental status (six of eight) or maintained a mental status comparable to that achieved with conventional therapy [lactulose or neomycin (two of eight)]. All decreased their blood ammonias on these medications and seven of eight improved their portal systemic encephalopathy index. It is suggested that these medications may be useful in the treatment of portal systemic encephalopathy.

Aged↗
PubMed1984

Portal-systemic shunting and the hemodynamic effects of nitroglycerin in the rat.

A hemodynamic response to oral nitroglycerin has been used recently to estimate the extent of portal systemic shunts in humans. We studied the hemodynamic effects of this drug in the rat with partial portal vein ligation, a model in which portal hypertension develops and the extent of portal-systemic collaterals can be measured. Two to ten days after the initial procedure, shunted and sham-operated controls received a continuous infusion of nitroglycerin into a jugular vein, the ileocolic vein, or intrajejunally. The response of systolic arterial pressure to intravenous nitroglycerin was similar in shunted and sham animals. The cumulative dose-response curve showed an earlier and more pronounced response in shunted rats receiving nitroglycerin intraportally, suggesting a marked increase in bioavailability. When the arterial response to nitroglycerin, infused intraportally at 1 microgram/kg X min, was compared to the extent of ileocolic shunting, measured with radioactive microspheres, a close correlation (r = 0.84) was seen; shunting values ranged from 0% (sham) to 97%. Additionally, in shunted rats a more pronounced response to intraportal, compared to intrajejunal, infusion suggested a contribution of the intestine to the first-pass elimination of the drug. The bioavailability of intraportal and intrajejunal nitroglycerin is influenced by the extent of portal systemic collaterals. A significant reduction in portal vein pressure in response to nitroglycerin seen in this animal model supports its testing as a therapeutic agent in portal hypertension.

Animals↗
PubMed2005

Effects of norepinephrine and acetylcholine on portal-systemic collaterals of common bile duct-ligated cirrhotic rat.

BACKGROUND: Catecholamine exerts profound vascular effects on vascular smooth muscle, and serum norepinephrine (Nepi) and sympathetic nervous activity are increased in cirrhosis. The vascular response of Nepi and acetylcholine (Ach) in portal-systemic collaterals of cirrhotic rats is unknown. The purpose of the present study was to investigate the effects of Nepi and Ach on portal-systemic collaterals of common bile duct-ligated (BDL) cirrhotic rats. METHODS: Perfusion studies were performed 6 weeks after BDL when hepatic cirrhosis was induced. Three series of experiments were performed in BDL rats: (i) the Nepi (10(-10) mol/L-10(-5) mol/L) vasoconstrictory responses with (n = 6) and without (n = 5) alpha1- (phentolamine, 5 x 10(-6) mol/L) or beta- (propranolol, 10(-5) mol/L) receptor antagonist (n = 6 and 5, respectively); (ii) the Ach (10(-8) mol/L-10(-5) mol/L) vasodilatory responses in Nepi- preconstricted portal-systemic collaterals in the absence (n = 7) or presence (n = 8) of N(pi)- L-nitro-arginine (NNA, 10(-4) mol/L); and (iii) the effect of indomethacin (10(-5) mol/L; n = 6) on Nepi responses. The collateral vascular responses were evaluated by the in situ collateral perfusion. RESULTS: Norepinephrine significantly increased the perfusion pressure and was inhibited by phentolamine (P < 0.05). The constrictive responses of Nepi were not significantly modified in the presence of propranolol (P > 0.05). Acetylcholine produced >50% relaxation of the Nepi-preconstricted collateral vessels and was inhibited by NNA (P < 0.05). In addition, indomethacin significantly enhanced the constrictive response of Nepi (P < 0.05). CONCLUSION: Norepinephrine has a vasoconstrictive effect on the portal-systemic collaterals of cirrhotic rats and this effect was mediated by alpha1-receptor. Both nitric oxide and prostaglandin are endogenous modulators in the collateral circulation of cirrhotic rats.

Acetylcholine↗