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PubMed1985

Mesocaval and distal splenorenal shunts: effect on hepatic function, hepatic hemodynamics, and portal systemic encephalopathy.

The effect of the mesocaval interposition shunt (n = 12) and the distal splenorenal shunt (n = 9) on the wedged hepatic venous pressure, the estimated hepatic blood flow, quantitative hepatic function, and the rate of portal systemic encephalopathy was evaluated in 21 patients who had bled from esophageal varices. After mesocaval shunt the wedged hepatic venous pressure was significantly reduced by 42% (from 26 +/- 3 mm Hg to 15 +/- 5 mm Hg, P less than 0.001) compared to 16% only (from 25 +/- 3 mm Hg to 21 +/- 2 mm Hg, P less than 0.005) after distal splenorenal shunt. The estimated hepatic blood flow also decreased significantly after mesocaval shunt by 61% (from 1.45 +/- 0.46 l/min to 0.56 +/- 0.25 l/min, P less than 0.001) compared to 29% (from 1.29 +/- 0.32 l/min to 0.91 +/- 0.39 l/min, P less than 0.05) after distal splenorenal shunt. Despite significantly different influences of both types of shunt operations on wedged hepatic venous pressure and estimated hepatic blood flow (P less than 0.001), postoperative changes of hepatic function were comparable in both groups of patients. The galactose elimination capacity, the initial plasma disappearance rate of Bromsulphalein, and the plasma ratio of valine, leucine, and isoleucine to phenylalanine and tyrosine were reduced by 13%, 26%, and 29%, respectively, after mesocaval shunt, compared to 12%, 25%, and 17% after distal splenorenal shunt. Only two patients of the mesocaval shunt group with the largest decrease in estimated hepatic blood flow developed portal systemic encephalopathy postoperatively, and the distal splenorenal shunt patients with their minor hemodynamic sequelae remained free of portal systemic encephalopathy.

Adult↗
PubMed1995

High-output congestive heart failure following transjugular intrahepatic portal-systemic shunting.

A hyperdynamic circulatory state with elevated cardiac output, decreased peripheral vascular resistance, and sodium retention occurs in patients with portal cirrhosis. Surgical portal-systemic shunts and transjugular intrahepatic portal-systemic shunts (TIPS) have been shown to worsen the high-output state in these patients. However, clinical evidence of high-output congestive heart failure has been reported only rarely to complicate cirrhosis. We describe a patient who developed high-output congestive heart failure with markedly elevated filling pressures after TIPS and had complete resolution of heart failure after liver transplantation.

Cardiac Output, High↗
PubMedDate not supplied

Two-stage transjugular intrahepatic porta-systemic shunt for patients with cirrhosis and a high risk of portal-systemic encephalopathy patients as a bridge to orthotopic liver transplantation: a preliminary report.

AIM: Placement of a transjugular intrahepatic porta-systemic shunt (TIPS) is a therapeutic option for the management of bleeding esophageal varices. However, the procedure is associated with an increased risk of portal-systemic encephalopathy (PSE). In this study, a two-stage modification of the standard TIPS technique was introduced for the management of variceal bleeding in cirrhotic patients with a high risk of PSE before liver transplantation. METHODS: The modified procedure was applied to four patients with cirrhosis, portal hypertension, and ascites. Two had a history of encephalopathy after variceal bleeding; the other two were encephalopathic at the time of the first stage of the modified procedure. In the first stage, a 6-mm diameter intrahepatic shunt was created using a Palmaz-Schatz stent. One month later, in the second stage, the lumen of the shunt was expanded to a diameter of 10 mm. RESULTS: Both stages of this TIPS procedure were undertaken without any associated adverse events. In particular, neither stage was followed by a deterioration of neurologic status. From completion of the second stage to undertaking orthotopic liver transplantation (a period of 2 to 6 months), no rebleeding from esophageal varices occurred. CONCLUSIONS: A two-stage TIPS procedure to reduce portal hypertension enables a more gradual adaptation to post-TIPS hemodynamic and metabolic changes than occurs after creation of a conventional TIPS. A two-stage TIPS procedure may be the method of choice for treating bleeding from esophageal varices in patients who have a high risk of developing PSE and give them a chance for liver transplantation.

Adult↗
PubMed2005

Effects of vasopressin on portal-systemic collaterals of cirrhotic rats.

OBJECTIVE: Arginine vasopressin (AVP) exerts a constrictive effect on the portal-systemic collaterals of non-cirrhotic portal hypertensive rats, but its effect on cirrhotic rats is unknown. The aim of this study was to investigate the response of AVP and the modulatory roles of nitric oxide and prostaglandin on collaterals of common bile duct-ligated (BDL) cirrhotic rats. MATERIAL AND METHODS: The collateral vascular responsiveness to graded concentrations of AVP (10(-10) - 3 x 10(-7) M) was tested by an in situ collateral perfusion system pretreated with Nomega-nitro-L-arginine (L-NNA, 100 microM), indomethacin (INDO, 10 microM), or both. The collateral responses to AVP with the pretreatment of a vasopressin V1 receptor antagonist d(CH2)5Tyr(Me) arginine vasopressin or a V2 receptor agonist 1-desamino-8-D-arginine vasopressin (DDAVP, 10(-10) - 3 x 10(-7) M) were also evaluated. RESULTS: The perfusion pressure of collaterals was significantly increased by AVP, and this effect was inhibited by the addition of the V1 receptor antagonist. DDAVP had no effect on the collaterals. Incubation with L-NNA or L-NNA plus INDO, but not INDO alone, significantly potentiated the constrictive effects of AVP. The constrictive effect of AVP in the combination group was similar to that in the L-NNA alone group. CONCLUSIONS: The results show that AVP produces a direct vasoconstrictive effect on the portal-systemic collaterals of BDL cirrhotic rats. The constrictive effect of AVP is mediated by the vasopressin V1, instead of V2, receptors. Nitric oxide may play a more important role than prostaglandin in modulating the collateral vascular response to AVP in BDL cirrhotic rats.

Animals↗
PubMed1980

Effect of spontaneous portal-systemic shunting on plasma insulin and amino acid concentrations.

To elucidate the relative contribution of parenchymal liver damage and spontaneous portal-systemic shunting to the reduction of peripheral insulin degradation rate and the decrease in plasma concentrations of three branched chain amino acids (valine, leucine, and isoleucine), plasma insulin, C-peptide, and amino acid concentrations were measured during oral glucose tolerance tests in 17 patients with liver cirrhosis, 10 with idiopathic portal hypertension, 5 hospitalized controls, and normal subjects. None of the patients had evidence of hepatic encephalopathy. Patients with idiopathic portal hypertension had histologically minimum hepatic fibrosis in spite of the existence of extensive exophageal varices. The molar ratio between plasma concentrations of C-peptide and insulin was significantly decreased in patients with cirrhosis, but not in those with idiopathic portal hypertension. In both patients with cirrhosis and idiopathic portal hypertension, the three branched chain amino acid levels were significantly decreased and the molar ratio between the concentrations of the three branched chain amino acids and two aromatic amino acids (tyrosine and phenylalanine) were markedly reduced. These results suggest that spontaneous portal-systemic shunting does not primarily contribute to the reduced degradation of insulin, but has a close relationship with the decrease in branched chain amino acid levels and in the molar ratio of plasma amino acids. In addition, the present data indicate that decreased branched chain amino acid levels in patients with cirrhosis is not merely ascribed to hyperinsulinemia and that the decrease in the molar ratio of plasma amino acids is not specific to the presence of hepatic encephalopathy.

Adult↗
PubMed2006

Successful portal-systemic shunt occlusion with balloon-occluded retrograde transvenous obliteration for portosystemic encephalopathy without liver cirrhosis.

A 68-year-old woman was admitted to the authors' hospital for hepatic encephalopathy. Her laboratory data and computed tomography findings were not suggestive of liver cirrhosis. Superior mesenteric angiography revealed an extrahepatic portal-systemic shunt with a main cause of hepatic encephalopathy. Despite treatment with branched-chain amino acid, lactulose, and kanamycin, hyperammonemia was prolonged, and the portal-systemic shunt was therefore treated with balloon-occluded retrograde transvenous obliteration. After the procedure, hyperammonemia was improved, and there were no signs of recurrent portal-systemic encephalopathy.

Aged↗
PubMed1992

Tetrapod-like hypothalamo-hypophysial portal system in the teleost Megalops cyprinoides (Broussonet).

A tetrapod-like hypothalamo-hypophysial portal system and a persistent bucco-hypophysial canal are present in Megalops cyprinoides. The complicated loops of the primary capillary plexus are seen on the ventral side of the infundibular floor and contact the perikarya of the nucleus lateralis tuberis and the preoptico-hypothalamo-neurohypophysial-neurosecretory tract. Although the pars intermedia receives part of its vascular supply from the pars distalis, the caudal hypophysial artery directly vascularizes the neurointermedia interface and forms the plexus intermedialis. The bucco-hypophysial canal is short and narrow in the fry and fingerlings but becomes long and tortuous as the fish grows. Megapopidae seem to be closer to the polypteriformids than to the teleosts. The possession of the pituitary portal system in megalopids may be a connecting link between the polypteriformids and other advanced teleosts.

Animals↗
PubMed1980

[Echographic exploration of the portal system. Echo-anatomy and symptomatology (author's transl)].

The authors describe the extra- and intra-hepatic echographic images of the portal system in the foetus and the adult on the basis of data from literature and their personal experience with angiographic comparisons and investigation of anatomical specimens. The knowledge gained by echography provides the means for a sure approach to systematisation of the liver and thus accurately identifies the site of focal processes (tumour, abscess, etc.) furnishes very useful information in a large number of pathological cases (foetal hypotrophy, portal hypertension, etc.), facilitates diagnostic and therapeutic instrumental exploration and will soon make it possible to carry out haemodynamic studies of the portal system through the addition of pulsed Doppler to the present echographs.

Adult↗
PubMed2001

[Magnetic resonance angiography with three-dimensional dynamic technique after contrast media administration for the study of the portal system ].

PURPOSE: To evaluate the feasibility of a contrast enhanced MR angiography (MRA) technique, using the latest 1.5 T MR tomoscan, to obtain optimal imaging of the portal system and compare the angiographic images with those obtained by color-Doppler and DSA. MATERIAL AND METHODS: Thirty patients (9 women and 21 men: average 53 years old) underwent contrast MRA of the portal vein, after portal hypertension had been diagnosed on the basis of clinical and chemical data and by color-Doppler. We used a dynamic 3D FFE T1-weighted breath - hold sequence during the arterial and venous phase after administering. 0.2 mmol/Kg of gadolinium-DTPA were at the rate of 2 ml/s. The contrast bolus was monitored using a 2D FFE T1-weighted sequence on a coronal plane. A FFE T1-weighted sequence was performed on axial plane before and after the dynamic sequence to obtain evaluate the a hepatic parenchyma. In the post processing phase MIP (maximum intensity projection) were reconstructed. We considered the patency of the portal venous system and the presence of cavernomatous and collateral circles; portal thrombosis was classified as partial or complete and as proximal or distal. RESULTS: Good quality MR angiographic images were obtained in 28 of the 30 cases examined; in 2 patients movement artefacts compromised the image quality. We observed a concordance between MRA and Doppler ultrasound in 79 vessels out of 84 (94%). A 97.5% concordance was found between MRA and DSA (82 vessels out of 84) with a sensitivity of 100% and a specificity of 97.3%. MRA was superior to DSA and Doppler ultrasound for evaluating large collateral shunts, above all gastro-esophageal and paraumbilical shunts, and complex anatomical conditions. CONCLUSIONS: Where available, advanced MRA technology with contrast enhancement should be used as a routine modality to study the anatomy and pathology and the portal system in all patients in whom Doppler ultrasound has yielded doubtful information. MRA is well-suited to obtain good vascular imaging before surgical or interventional procedures.

Adult↗
PubMed1991

Evaluation of portal-systemic shunting in rats from mesenteric and splenic beds.

In rats with partial portal vein ligation, 95 +/- 0.9% of the splenic blood flow is shunted from the portal to the systemic circulation when an intrasplenic injection of microspheres is used to determine the degree of shunting. Despite this magnitude of portal-systemic shunting, several biochemical and endocrine consequences of portal-systemic shunting occur at levels below what is expected for the degree of shunting found. In an effort to resolve these discordant findings, shunting from both the splenic and the mesenteric bed was studied in anesthetized portal hypertensive rats with various degrees and/or duration of portal vein stenosis. The shunting from the mesenteric bed averaged 66.7 +/- 29.9% (range 5.1-99.1%) and was influenced both by the degree and duration of portal vein stenosis. In contrast, shunting from the splenic bed averaged 97.3 +/- 4.0% (range 79-99.9%) and demonstrated no variation between groups determined by the degree of portal vein stenosis. The shunting from the splenic bed was consistently greater than that found from the mesenteric bed. Mesenteric but not splenic shunting correlated with serum bile acid levels. Mesenteric shunting was related inversely to the weight-adjusted liver mass and to serum testosterone levels. Based upon these data obtained in portal hypertensive rats, it is concluded that splenic injections of microspheres overestimate portal-systemic shunting. In contrast, mesenteric injections of microspheres yield values for shunting that correlate well with independently determined biochemical and endocrine consequences of shunting. These observations support the validity of the mesenteric shunting measurements obtained.

Animals↗
PubMed1983

Standard and higher doses of bromocriptine for severe chronic portal-systemic encephalopathy.

In a single-blind, cross-over fashion we assessed the therapeutic value of the dopamine agonist bromocriptine at doses of 15 and 20 mg/day plus cleansing enemas, versus the vigorous standard treatment of neomycin 6 g/day plus cleansing enemas. We studied four patients with severe chronic portal systemic encephalopathy. All the patients presented elevated prolactin levels. During the study the following parameters were assessed: mental state, number connection test times, frequency of asterixis, EEG, blood ammonia, and serum prolactin levels. In all but one patient, portal systemic encephalopathy parameters improved during the standard therapy, as opposed to both bromocriptine periods. During the period with 30 mg/day of bromocriptine all four patients developed precoma, although later one patient improved. Serum prolactin levels were rapidly suppressed during both bromocriptine periods. Prolactin levels did not correlate with changes in mental state. In patients with severe portal systemic encephalopathy, treatments with 15 and 30 mg of bromocriptine plus cleansing enemas were no better than the standard therapy.

Bromocriptine↗
PubMed1998

Cerebral blood flow velocity in patients with subclinical portal-systemic encephalopathy.

UNLABELLED: Alterations in cerebral blood flow (CBF) are implicated in the etiology of portal-systemic encephalopathy. We hypothesized that CO2 reactivity of the cerebral circulation may be impaired in subjects with chronic liver disease (CLD) who also had subclinical portal-systemic encephalopathy (SPSE). We compared the relationship between PETCO2 and cerebral blood flow velocity in 10 patients with CLD with those of 10 healthy control subjects. Middle cerebral artery mean blood flow velocity (MCAMFV) was measured using transcranial Doppler during rest, hyperventilation, and hypoventilation. The degree of SPSE was quantified by using psychometric testing. Patients with CLD had poorer psychometric test scores compared with control subjects. Patients with CLD had lower PETCO2, MCAMFV, and blood pressure values and higher heart rates, differing from control subjects in all ventilation states. However, CO2 reactivity, the rate of change in MCAMFV to changes in ventilation (expressed as percent change in CBF velocity per mm Hg change in PETCO2) was similar for both groups (4.6% +/- 0.6% vs 4.2% +/- 0.5% for patients with CLD versus control subjects, P = 0.15). IMPLICATIONS: Psychometric test scores in patients with chronic liver disease revealed subclinical impairment compared with control subjects. Transcranial Doppler measurements of middle cerebral artery blood flow with varying PETCO2 were conducted, but the CO2 response of patients with liver disease was within the range of control subjects.

Adult↗
PubMed1999

[Disappearance of globus pallidus hyperintensity in a patient with portal-systemic encephalopathy after occlusion of the shunt vessel].

A 67-year-old woman was admitted to our hospital with confusion and asterixis on January 23, 1994. She had had the same symptoms repeatedly. On admission she was disorientated, and had slurred speech and asterixis. Laboratory data showed hyperammonemia (84 micrograms/dl) with a poor ICG hepatic clearance (ICG15min = 32%), although hepatic failure did not exist. Abdominal ultrasonography, CT scan and liver biopsy showed no evidence of cirrhosis. Celiac arteriography revealed a large shunt vessel connecting the portal vein to the left renal vein. A 1.5 T magnetic resonance imaging (MRI) demonstrated a bilateral and symmetrical hyperintensity of the globus pallidus in the T1-weighted images. Portal-systemic encephalopathy recurred repeatedly in spite of the conservative therapy, and there was no evidence of the portal hypertension. Therefore, the operative procedure of ligation of the shunt vessel was done on February 21, 1995. After the operation, blood ammonia level and ICG hepatic clearance were normalized. She became free from encephalopathy. Twenty-seven months after the operation, the hyperintensity of the globus pallidus in the T1-weighted images completely disappeared. There have been several reports describing that the globus pallidus alterations on the T1-weighted images in patients with liver cirrhosis, manganese intoxication and portal-systemic encephalopathy. To our knowledge, this is the first case that the hyperintense signal of the basal ganglia in a patient with portal-systemic encephalopathy disappeared completely after occlusion of the shunt vessel.

Aged↗
PubMedDate not supplied

Acidifying enemas (lactitol and lactose) vs. nonacidifying enemas (tap water) to treat acute portal-systemic encephalopathy: a double-blind, randomized clinical trial.

A double-blind, controlled trial to study the efficacy of acidifying enemas of lactitol, a new galactoside-sorbitol disaccharide, and lactose vs. nonacidifying tap-water enemas was performed in 45 episodes of acute portal-systemic encephalopathy. At the time of randomization, all patients had encephalopathy of at least Grade 2+ severity, delay in the performance of number connection tests and hyperammonemia. A sequential analysis was performed which revealed after the inclusion of the first 20 patients, a significant failure of the nonacidifying enemas as compared to the lactitol enemas (p less than 0.004). The tap-water enema group was, therefore, suspended but the rest of the study continued after rerandomization for lactose and lactitol groups. A favorable response to treatment was obtained in 19 (86%) of the patients receiving lactitol enemas and in 14 (78%) of those receiving lactose enemas. A similar significant improvement in portal-systemic encephalopathy parameters and index was observed after both treatments. Both types of acidifying enemas induced a significant pH decrease in stool (p less than 0.05). These data suggest that acidifying agents like lactose and lactitol are effective and superior to tap-water enemas for the treatment of acute nitrogenous portal-systemic encephalopathy.

Ammonia↗
PubMed2002

Bleeding esophagogastric varices from extrahepatic portal hypertension: 40 years' experience with portal-systemic shunt.

BACKGROUND: This article discusses the largest and longest experience reported to date of the use of portal-systemic shunt (PSS) to treat recurrent bleeding from esophagogastric varices caused by extrahepatic portal hypertension associated with portal vein thrombosis (PVT). STUDY DESIGN: Two hundred consecutive children and adults with extrahepatic portal hypertension caused by PVT who were referred between 1958 and 1998 after recovering from at least two episodes of bleeding esophagogastric varices requiring blood transfusions were managed according to a well-defined and uniformly applied protocol. All but 14 of the 200 patients were eligible for and received 5 or more years of regular followup (93%); 166 were eligible for and received 10 or more years of regular followup (83%). RESULTS: The etiology of PVT was unknown in 65% of patients. Identifiable causes of PVT were neonatal omphalitis in 30 patients (15%), umbilical vein catheterization in 14 patients (7%), and peritonitis in 14 patients (7%). The mean number of bleeding episodes before PSS was 5.4 (range 2 to 18). Liver biopsies showed normal morphology in all patients. The site of PVT was the portal vein alone in 134 patients (76%), the portal vein and adjacent superior mesenteric vein in 10 patients (5%), and the portal and splenic veins in 56 patients (28%). Postoperative survival to leave the hospital was 100%. Actuarial 5-year, 10-year, and 15-year survival rates were 99%, 97%, and 95%, respectively. Five patients (2.5%), all with central end-to-side splenorenal shunts, developed thrombosis of the PSS, and these were the only patients who had recurrent variceal bleeding. During 10 or more years of followup, 97% of the eligible patients were shown to have a patent shunt and were free of bleeding. No patient developed portal-systemic encephalopathy, liver function tests remained normal, liver biopsies in 100 patients showed normal architecture, hypersplenism was corrected. CONCLUSION: PSS is the only consistently effective therapy for bleeding esophagogastric varices from PVT and extrahepatic portal hypertension, resulting in many years of survival, freedom from recurrent bleeding, normal liver function, and no encephalopathy.

Adolescent↗
PubMed1988

Changes of portal systemic shunting after sclerotherapy and/or partial splenic embolization observed by thallium-201 per rectal administration.

Tl-201 per-rectal scintigraphy was performed before and after injection sclerotherapy of esophageal varices and/or partial splenic embolization in patients with esophageal varices to observe the changes of portal systemic shunting by these treatments. The changes in the heart-to-liver uptake ratio of Tl-201 after injection sclerotherapy ranged widely from a decrease to an increase with a mean change rate (mean of the absolute value of change rate) and one standard deviation of 19.0 +/- 19.9%. By partial splenic embolization the heart-to-liver uptake ratio was decreased significantly with the mean change rate and one standard deviation of 26.2 +/- 17.4% (P less than .05). This noninvasive and simple method seems to be useful in evaluating pathophysiological changes of portal systemic shunting observed from inferior mesenteric vein blood flow after treatments of portal circulation system.

Administration, Rectal↗