Splenorenal Shunt Research Articles

How to handle a huge portosystemic shunt in adult living donor liver transplantation with a small-for-size graft: Report of a case

Little attention has been paid to a ligation of the spontaneous portosystemic shunt in adult living donor liver transplantation (LDLT). A 33-year-old Japanese man with cryptogenic liver cirrhosis accompanied by a huge splenorenal shunt underwent LDLT. Acute cellular rejection produced "to and fro" portal venous flow on postoperative day (POD) 10. Steroid bolus therapy reversed the rejection, but the recovery of the portal venous flow was incomplete and the recipient subsequently started to have episodes of encephalopathy. Angiography showed portal hypoperfusion and portal flow steal via a huge splenorenal shunt. The patient underwent a shunt occlusion on POD 58. Portography showed marked improvement of the portal hypoperfusion. The encephalopathy thereafter dramatically reversed and the patient was discharged with no complications related to shunt ligation on POD 110. This case suggested that a ligation of a huge portosystemic shunt should therefore be considered at the time of transplantation, even when a relatively small graft is implanted.

Surgical portosystemic shunts and the Rex bypass in children: a single-centre experience

ObjectivesThis study aimed to illustrate the indications for, and types and outcomes of surgical portosystemic shunt (PSS) and/or Rex bypass in a single centre. MethodsData were collected from children with a PSS and/or Rex bypass between 1992 and 2006 at Mount Sinai Medical Center, New York. ResultsMedian age at surgery was 10.7 years (range 0.3–22.0 years). Indications included: (i) refractory gastrointestinal bleeding in portal hypertension associated with (a) compensated cirrhosis (n= 12), (b) portal vein thrombosis (n= 10), (c) hepatoportal sclerosis (n= 3); (ii) refractory ascites secondary to Budd–Chiari syndrome (n= 3), and (iii) familial hypercholesterolaemia (n= 4). There were 20 distal splenorenal, four portacaval, three Rex bypass, two mesocaval, two mesoatrial and one proximal splenorenal shunts. At the last follow-up (median 2.9 years, range 0.1–14.1 years), one shunt (Rex bypass) was thrombosed. Two patients had died and two had required a liver transplant. These had a patent shunt at last imaging prior to death or transplant. ConclusionsPortosystemic shunts and Rex bypass have been used to manage portal hypertension with excellent outcomes. In selected children with compensated liver disease, PSS may act as a bridge to liver transplantation or represent an attractive alternative.

Postshunt Hepatic Encephalopathy in Liver Transplant Recipients

Preexisting spontaneous portosystemic shunts increase the risk of posttransplantation portal vein thrombosis. Portosystemic shunts may also be placed surgically to manage posttransplant portal vein stenosis/thrombosis. Both types may be complicated by hepatic encephalopathy. The database of a major tertiary medical center from 1999 to 2006 was searched for liver transplant recipients with hepatic encephalopathy and stable liver function. The medical and imaging files were reviewed for risk factors, management, and outcome. Of the 244 patients who underwent liver transplantation during the study period, four (1.6%) met the inclusion criteria. Median age at transplantation was 49 years (range 39-54); median time to the first episode of hepatic encephalopathy after transplantation was 23 months (range 2-40). In two patients, a distal splenorenal shunt placed at 1 and 7 months after transplantation to treat portal vein thrombosis led to hepatic encephalopathy at 1 and 33 months later. Both responded to medical therapy. The other two patients had spontaneous splenorenal shunts, and hepatic encephalopathy appeared 33 months and 12 months after transplantation. Treatment consisted of transhepatic percutaneous portal vein dilatation with stent insertion in the first patient and interposition of a venous graft between the superior mesenteric and left intrahepatic portal veins to reroute splanchnic flow in the second patient. Portosystemic shunts in liver transplant recipients with stable graft function may be associated with hepatic encephalopathy. Pretransplant assessment to detect unknown spontaneous shunts is important. Restoration of portal flow is the preferred procedure in this setting.

Percutaneous transretroperitoneal direct approach to occlude a major shunt in a patient with extrahepatic portal–systemic encephalopathy

A 73-year-old woman had sudden dystrophy and amnesia in our hospital. Her serum ammonia level was high. Marked collateral vessels from the splenic vein to the left renal vein around the spleen were seen on a computed tomography (CT) scan with contrast enhancement. An abdominal angiogram showed that the direction of the splenic vein was hepatofugal on superior mesenteric arterial portography, with a marked splenorenal shunt on splenic arterial portography. Hepatic encephalopathy due to a marked extrahepatic portal-systemic shunt was diagnosed. Transjugular retrograde obliteration (TJO) was attempted, but the catheter and guide wire could not selectively approach the splenorenal shunt because of many outflow routes. We punctured the vessels from the left side of the back under ultrasonographic guidance. We injected microcoils and ethanolamine oleate to completely obliterate the shunt. Marked collateral vessels showed no venous flow on a CT scan after treatment. The serum ammonia level was in the normal range. There has been no recanalization of the shunt vessels for 4 years after treatment. Hepatic encephalopathy has not recurred, and no other collateral vessels have developed. To our knowledge, this is the first report to document the use of a percutaneous transretroperitoneal direct approach to occlude a major shunt in a patient with extrahepatic portal-systemic encephalopathy.

AASLD practice guidelines the role of transjugular intrahepatic portosystemic shunt (TIPS) in the management of portal hypertension update 2009

The 2009 update of the American Association for the Study of Liver Diseases (AASLD) Practice Guideline “The Role of Transjugular Intrahepatic Portosystemic Shunt (TIPS) in the Management of Portal Hypertension” is now posted online at www.aasld.org. This is the first update of the original guideline published in 2005.1 DSRS, distal splenorenal shunt; TIPS, transjugular intrahepatic portosystemic shunt. The key changes in the 2009 guidelines are new recommendations on the use of covered versus bare stents in the creation of the TIPS. Use of expanded polytetrafluoroethylene (ePTFE)-covered stents is now preferred. The lower risk of shunt dysfunction and perhaps improved outcomes using covered as opposed to bare stents are the basis for this recommendation.2, 3 Creation of a TIPS increases the risk of hepatic encephalopathy but the prophylactic use of nonabsorbable disaccharides or antibiotics does not appear to reduce this risk and is not recommended.4 The value of TIPS versus a surgical shunt in the prevention of variceal rebleeding in patients who have failed medical therapy has been clarified by the publication of a controlled trial comparing TIPS to distal splenorenal shunt (DSRS).5 Both were effective in preventing rebleeding (rebleeding incidence in 5.5% of DSRS versus 10.5% of TIPS; not significant) with no difference in encephalopathy or survival. The patients in whom TIPS was performed required significantly more interventions to maintain patency because of the use of bare stents. A cost analysis showed TIPS to be slightly more cost effective than DSRS at year 5,6 and these two approaches are now considered to be of equal efficacy in the prevention of variceal rebleeding. The other significant change to the guidelines is how TIPS should be used in the management of patients with Budd-Chiari syndrome. A large (221 patients) retrospective study was published in which patients who failed to improve with use of anticoagulation had a TIPS created (133 patients). One-year and 10-year transplant-free survival was 88% and 69%, respectively, which is better than predicted.7 TIPS patency was best in those who received a covered stent. The recommendation now is for creation of a TIPS in those who fail to improve with anticoagulation.

Functional Hepatic Flow Can Predict the Hepatic Reserve Function in Surgical Cirrhotic Patients

Aim: To evaluate hepatic reserve function by monitoring functional hepatic flow in cirrhotic patients admitted for surgical treatments. Methods: Thirty-seven biopsy-proved cirrhotic patients with portal hypertension and 10 healthy volunteers entered the study. Eleven were Child-Pugh class A, 18 class B, and 8 class C. Eight patients undergone Transjugular intrahepatic portosystemic shunt (TIPS), 10 were submitted to the combination of TIPS and portal-azygous disconnection, 10 were treated with surgical portal-azygous disconnection, and 9 were treated with the combination of portal-azygous disconnection and spleno-renal shunt. The functional hepatic flow (FHF) and total hepatic flow (THF) were determined by means of modified hepatic clearance of D-sorbitol combined with duplex Doppler color sonography. Portal pressure was measured directly by portal vein catheterization. Results: Portal blood flow, hepatic artery flow, and THF significantly increased in cirrhotic patients compared to the controls, while FHF was significantly reduced. Both portal pressure and FHF decreased in cirrhotic patients submitted to TIPS, the combination of TIPS and portal-azygous disconnection, or the combination of portal-azygous disconnection and spleno-renal shunt (p <.05). FHF decreased significantly in patients treated with TIPS compared to other patients (p <.01). The portal pressure decreased in patients treated with portal-azygous disconnection while FHF maintained no changes (p >.05). Conclusions: Monitor of FHF in cirrhotic patients is valuable to predict different hepatic reserve function in patients receiving different surgical operations.

Portosystemic shunts in a large cohort of patients with liver cirrhosis: detection rate and clinical relevance

This study aimed to determine the detection rate and clinical relevance of portosystemic collaterals. We studied 326 cirrhotics. Portosystemic collaterals, portal vein diameter, and splenic area were evaluated by color Doppler sonography; esophageal varices were detected by endoscopy. Of the cirrhotics, 130 had portosystemic collaterals (39.9% total, left gastric vein 11%, paraumbilical vein 7.4%, splenorenal shunts 13.8%, and combined shunts 7.7%). Cirrhotics without portosystemic collaterals or with a paraumbilical vein had a significantly narrower portal vein diameter than cirrhotics with a left gastric vein (P < 0.001). Cirrhotics with a paraumbilical vein had a significantly smaller splenic area than cirrhotics with a left gastric vein (P < 0.001), splenorenal shunts (P < 0.001), combined shunts (P < 0.001), or without portosystemic collaterals (P < 0.05). A significant association between portosystemic collaterals and Child's classes or presence and type of esophageal varices was found (P < 0.0001 and P = 0.0004, respectively). The highest prevalence of Child's class C and large (F-3) esophageal varices was found in cirrhotics with a left gastric vein (41.7% and 36.1%, respectively), whereas esophageal varices were absent in 47.4% of cirrhotics without portosystemic collaterals and in 58.3% of cirrhotics with a paraumbilical vein. The left gastric vein is associated with some sonographic and clinical markers of disease severity, whereas the absence of portosystemic collaterals or the presence of paraumbilical veins seems to identify cirrhotics with markers predictive of a more favorable clinical course.

Stent graft closure of a high flow splenorenal shunt in a patient after liver transplantation

We describe a patient after liver transplantation with a preexisting surgical splenorenal shunt close to the confluence of the splenic and superior mesenteric veins and a wide, short communication between the splenic and renal veins. To close the shunt, an inferior vena cava filter was inserted in the shunt and a vascular plug was placed in the splenic vein inside the filter. When this failed to stop the flow through the shunt, a covered stent was deployed at the superior mesenteric vein-portal vein junction.

Extrahepatic portal venous obstruction: The effects of early ligation of splenic artery during splenectomy

Aim:To objectively demonstrate the gain in blood volume and blood components following early ligation of splenic artery during splenectomy and splenorenal shunts in children with extra hepatic portal venous obstruction (EHPVO).Methods:Twenty-eight children (20 males and 8 females, mean age: 9.9 (±3.2) years) with EHPVO and hypersplenism were recruited. We followed a protocol of systematically locating and ligating the splenic artery first, followed by a 30-minute waiting period to allow the massive spleen to decongest via the splenic vein and venous collaterals and then completing the splenectomy by standard procedure. No intravenous fluid was administered during this 30-minute period. Blood samples were drawn just prior to splenic artery ligation and soon after splenectomy for the estimation of hematological and biochemical parameters.Results:We noticed a highly significant increase in the hemoglobin, hematocrit, leukocyte, platelet, and RBC counts by early ligation of the splenic artery (p < 0.0004). The gain in hemoglobin and hematocrit was equivalent to a transfusion of atleast 100-150 ml of packed RBC. The increase in platelet count was equivalent to a platelet transfusion of atleast 4 units of platelet concentrates in an adult. There is a positive correlation between the splenic weight and the platelet gain (p= 0.0568) and the splenic volume on preoperative imaging and the platelet gain (p= 0.0251).Conclusion:Early ligation of the splenic artery during splenectomy results in passive splenic decongestion and thereby a significant gain in blood components. This protocol appears to be a feasible blood conservation method to avoid blood transfusions in this group of hypersplenic EHPVO patients.

Imaging liver transplantation candidates using gadolinium enhanced MDCT angiography

Aim: To report our experience with gadolinium enhanced computed tomography angiography (Gd-CTA) for end-stage liver disease patients who are candidates for liver transplantation as an alternative to iodinated contrast enhanced CTA and gadolinium enhanced magnetic resonance (MR) angiography. Materials and methods: Seventeen patients with end-stage liver disease were evaluated with Gd-CTA. The patients were 10 men (58.8%) and 7 women (41.1%) (age range: 37-59 years). Multidetector CT (MDCT) was performed using 16-detector-row CT scanners. 3D images of the celiac artery, superior mesenteric artery, portal vein, and inferior vena cava (IVC) were obtained for thorough assessment using multiple plane reconstruction and maximum-intensity projection. Adequate images were defined by complete opacification of the celiac, superior mesenteric, hepatic propria, bilateral hepatic arteries, main portal vein and bilateral intrahepatic portal branches, and IVC. Results: All 17 Gd-CTAs were rated as diagnostic. Adequate CT arteriography (celiac, common hepatic, hepatic propia, and bilateral hepatic artery) and portography were obtained in all the patients. Engorged gastric and coronary varices were detected in 5 patients (29.4%). Severe splenorenal shunt was found in 2 patients (11.7%). Thrombus of the portal vein was observed in 3 patients (17.6%). The radiological findings and operational findings were not discordant in any of the operated patients. Conclusion: The degree of enhancement and image quality achieved using these gadolinium-enhanced MDCT angiographies appear adequate for angiographic evaluation of liver transplantation. Therefore, the use of 3D Gd-CTA in selected cases and settings can be advantageous in the pretransplantation evaluation.

Function of portal pressure during operation on the choice of surgical approaches in portal hypertension

To investigate the relationship between perioperative free portal pressure (FPP) after devascularization or spleno-renal shunt operation added devascularization and rebleeding or encephalopathy in patients with portal hypertension, and evaluate the relationship between dynamic changes of FPP and surgical approaches. The clinical data of 170 patients with portal hypertension receiving devascularization or devascularization with spleno-renal shunt operation (combination group) from January 2001 to December 2007 were retrospectively analyzed. All patients were divided into three groups: low pressure group [L group, after devascularization FPP <or= 22 mm Hg (1 mm Hg = 0.133 kPa), n = 43], high pressure group (H group, FPP > 22 mm Hg, n = 60) and combination group (C group, n = 47). There was no significant difference in preoperative Child-Pugh score and pre-operation FPP (P > 0.05) among the three groups. Perioperative FPP, morbidity of rebleeding and encephalopathy were compared with each other. The values of postoperative FPP were (27.1 +/- 1.9) mm Hg, (20.8 +/- 1.8) mm Hg and (21.5 +/- 2.2) mm Hg among the H group, L group and C group respectively. The rebleeding rates were 21.7%, 4.6% and 4.5% among the three groups respectively. All the values in H group were higher than those in L group and C group remarkably. The encephalopathy rate in C group (10.4%) was higher than that in L group (7.0%) or H group (3.3%), but there were no statistical significance (P > 0.05). FPP after splenectomy and devascularization may be a basis of choice of surgical approaches in portal hypertension. The spleno-renal shunt operation should be performed in the patients when FPP is over 22 mm Hg after devascularization.

Significance of Portosystemic Shunt on Graft Survival in Liver Transplantation: A Rat Model

Aims Distal splenorenal shunt effectively controls bleeding from esophageal and gastric varices but has a different effect on liver transplantation. This study sought to develop an animal model in rats to mimic the recipient with a portosystemic shunt and to investigate its hemodynamic consequences on liver transplantation. Methods We prepared 5 groups of allogeneic or syngeneic rat liver transplantation models with versus without portosystemic shunt, to investigate its effects on graft survival and portal flow. To explore the effects of excessive portal flow on graft survival in small-for-size liver transplantation, we transplanted partial liver grafts into syngeneic recipients. Results In allogeneic combinations, graft survival among the shunt group was shortened compared with their control counterparts. The graft survival of the large shunt group was significantly lower than that of a small shunt or without shunt group in a syngeneic liver transplantation model. Portal blood pressure of the large shunt group was significantly lower than that of the small shunt group. In contrast, excessive portal flow resulted in dysfunction of liver graft in small-for-size liver transplantation. Conclusions These results suggested that reduction in portal flow by portosystemic shunt lead to an acceleration of acute rejection and subsequent liver graft dysfunction, but it may be applicable to regulate the excessive portal flow in small-for-size transplantations. This study showed a valuable model mimicking the recipient with a portosystemic shunt.

Pharmacological effects are model specific in animal models of portal hypertension

Pharmacological effects are model specific in animal models of portal hypertension

Budd-Chiari syndrome due to hepatic vein obstruction without inferior vena cava obstruction.

Pulsed and color Doppler US demonstrated regular blood fl ow with a forward fl ow direction in the IVC (Fig. 1a). Although the MHV retained blood fl ow with a forward direction, the RHV did not reveal any blood fl ow signal (Fig. 1b). Detailed evaluation of blood fl ow in the LHV was prevented by a cardiac motion artifact. Blood fl ow in both the intrahepatic portal vein and the portal trunk had a to-and-fro or reversed fl ow appearance (Fig. 1c), and that in the splenic vein was a continuous reverse fl ow, as the patient had a large splenorenal shunt. These US fi ndings strongly suggested hepatic vein obstruction, that is, Budd– Chiari syndrome, with development of a portosystemic collateral vessel.

Resolution of Portal Hypertension Following Steroid Therapy for Hepatic Sarcoidosis

Purpose: Granulomatous diseases including sarcoidosis are an unusual cause of pre-sinusoidal portal hypertension. We present a case of a patient with both Hepatitis C and sarcoidosis who had significant improvement in portal hypertension following steroid therapy. Methods: A 51 year old Caucasian woman was diagnosed in 2001 with chronic Hepatitis C during a workup for elevated liver enzymes. She was offered treatment with interferon and Ribavirin but she refused. In 2002, she developed peripheral edema, severe anemia, grade 2 esophageal varices and significant splenomegaly. A liver biopsy showed grade 2 hepatitis with stage 3 fibrosis. In 2004, she developed jaundice for the first time and had worsened splenomegaly with secondary pancytopenia. She had gastric varices and grade 3 esophageal varices which required banding. She had never developed encephalopathy. She was offered a TIPS procedure and splenectomy but she came to our institution in 2005 for a second opinion. Laboratory studies showed pancytopenia, mildly elevated liver enzymes, normal albumin and INR. Contrasted CT scan showed extensive abnormal lymphadenopathy in the abdomen, massive splenomegaly, extensive portosystemic varices, mild ascites, normal appearing liver and a spontaneous spleno-renal shunt. Her previous biopsy was reviewed at our institution and showed multiple large granulomas consistent with sarcoidosis along with stage 3 fibrosis. Transjugular liver biopsy was repeated and confirmed the findings. Hepatic venogram showed a hepatic venous pressure gradient (HVPG) of 19 mmHg. Serum angiotensin converting enzyme level was normal. Bone marrow biopsy showed hypercellularity with no evidence of lymphoma. A diagnosis of portal hypertension secondary to sarcoidosis of the liver was made because the fibrosis in the liver was not considered advanced enough to explain the severity of portal hypertension. Results: Prednisone 60 mg a day was started to treat the sarcoidosis and was slowly tapered. Six months later, a repeat hepatic hemodynamic study showed HVPG of 7 mmHg, while still on Prednisone 20 mg a day. CT showed resolution of ascites and repeat endoscopy showed no esophageal or gastric varices. In one year, HVPG decreased further to 5 mmHg. Currently, she is on Prednisone 2.5 mg a day without any further worsening of her portal hypertension. Conclusion: This is a patient with non cirrhotic stage Hepatitis C who had portal hypertension out of proportion to her chronic viral liver disease. She was found to have extensive sarcoidosis in the liver which ultimately was treated with steroids and the portal hypertension resolved. This report supports the use of steroid therapy in patients with sarcoidosis who have portal hypertension.

Effects of combined procedure and devascularization alone on hyperdynamics of the portal venous system in patients with portal hypertension

Shunts and devascularizations have totally different effects on the hemodynamics of the portal venous system. The actual results of pericardial devascularization (PCDV) alone and conventional splenorenal shunt combined with pericardial devascularization (combined procedure, CP) should be determined by more clinical observations. This study aimed to evaluate effects on hemodynamics in the portal venous system after CP and PCDV only. In 20 patients who received CP and 18 who received PCDV, hemodynamic parameters of the portal venous system were studied by magnetic resonance angiography 1 week before and 2 weeks after operation. Free portal pressure (FPP) was continuously detected by a transducer during the operations. Compared to the preoperative data, a decreased flow in the portal vein (PVF) [(563.12 ± 206.42) mL/min vs (1080.63 ± 352.85) mL/min, P 0.05] had no significant decrease, while FPP [(21.50 ± 2.67) mmHg vs (24.40 ± 3.78) mmHg, P < 0.01] had a significant decrease as compared with that in the PCDV group. PVF and FPP could be decreased by both surgical procedures, but the effect of decreasing FPP was much better in the combined procedure than in PCDV alone. Further, there was no significant difference in PVF between the two groups. It is suggested that the combined surgical procedure could integrate the advantages of shunting with those of devascularization, as well as maintaining the normal anatomic structure of hepatic portal system, thus it should be one of the best choices for patients with portal hypertension when surgical interventions are considered.

Vascular actions of the prostacyclin receptor antagonist BAY 73-1449 in the portal hypertensive rat

We have investigated the actions of the postacyclin receptor antagonist BAY 73-1449 on shunt vessel development and shunt flow in the portal vein ligated portal hypertensive Wistar rat in vivo. BAY 73-1449 (0.1–1 mg/kg), given intravenously, did not significantly reduce mesenteric inflow, but significantly reduced splenic shunt vessel outflow, compared to the effects of vehicle, in anaesthetized portal vein ligated rats as measured by shunt vessel conductance. There were no differences between portal vein ligated animals treated, beginning just before portal vein ligation, with vehicle for 7 days and animals treated for 7 days with BAY 73-1449 (1–5 mg/kg, s.c.) in the degree of porto-systemic shunting, as measured by the radioactive microsphere technique in anaesthetized rats. Portal pressure was similar in animals treated with vehicle or BAY 73-1449. It is concluded that the prostacyclin receptor antagonist BAY 73-1449 can acutely reduce shunt vessel blood flow in portal hypertensive rats.

Evaluation of the graft hemodynamics after liver transplantation by CT perfusion

Objective To investigate the influence factors on the graft hemodynamics after liver transplantation by CT perfusion(CTP).Methods Thirty three liver recipients received CT angiography (CTA)and CTP after liver transplantation.The cases would be excluded when their peak values of the aorta enhancement on time-density curves were out of 95%confidence level.The 95% confidence levels of the hepatic artery perfusion(HAP),portal vein perfusion(PVP),total liver perfusion(TLP)and hepatic perfusion index(HPI)were calculated based on the recipients without postoperative complications and named them as references to those with complication.Results Twenty nine recipients were enrolled in the study.15 of them had no postoperative complication while the other 14 had.The 95% confidence levels of HAP,PVP,TLP and HPI on the 15 recipients without complications were(0.1509-0.3183),the 14 cases with complications.HAP decreased in 7 cases,5 of them had hepatic artery stenosis and 3 of them had splenomegaly.HAP increased in 2 cases.both of them had portal vein stenosis.PVP decreased in 13 cases,8 of them had portal vein stenosis,portal vein thrombosis or occlusion,4 of them had splenorenal shunts and 2 of them had fatty liver.TLP decreased in 12 cases and coincident with PVP decreasing.Only 2 cases had HPI decreasing accompanied with HAP decreasing.Conclusion The hepatic blood perfusion through the hepatic artery and portal vein could be quantitatively measured non-invasively by CTP.The severity and the subtypes of the hepatic ischemia could be evaluated objectively,which is helpful for treatment guidance. Key words: Liver transplantation; Postoperative complications; Tomography,X-ray computed

Hemodynamic effects of the early and long-term administration of propranolol in rats with intrahepatic portal hypertension

Background and aims The aims of this study were to evaluate a preventive effect on collateral venous circulation of long-term administration of propranolol in intrahepatic portal hypertensive rats. Methods Eighty-six Sprague-Dawley rats were allocated to two models of hepatic fibrosis, bile duct-ligated (BDL) induced and carbon tetrachloride (CCl(4)) induced. Each model was divided into two groups: one receiving placebo and the other propranolol (75 mg kg(-1) d(-1)). Mean arterial pressure (MAP), heart rate (HR), portal pressure (PP), cardiac index (CI), vascular systemic resistance, and splenorenal shunt blood flow (SRS-BF) were measured in anesthetized rats. Results In the BDL model, no significant hemodynamic changes were observed in the propranolol group compared with the placebo group. In CCl(4)-induced rats, HR (390 +/- 50 vs. 329 +/- 51 beats/min, P = .001), CI (44 +/- 11 vs. 34 +/- 10 ml/min, P = .004), PP (15.4 +/- 3.0 vs. 13.4 +/- 1.9 mmHg, P = .045), and SRS-BF (1.4 +/- 1.1 vs. 1.0 +/- 1.0 ml/min, P = .047) were significantly lower in the propranolol group. Conclusions This study showed that propranolol has a significant hemodynamic effect only in the CCl(4) model and suggested a model-dependent effect of propranolol.

Pulmonary Hypertension in Patients With Congenital Portosystemic Venous Shunt: A Previously Unrecognized Association

Pulmonary arterial hypertension has been reported to be observed in association with acquired portal hypertension. However, the contribution of congenital anomalies occurring in the portal system to the development of pulmonary arterial hypertension remains to be elucidated. Nine patients with congenital portosystemic venous shunt were studied from January 1990 through September 2005. Patent ductus venosus was detected in 5 patients, including 3 patients with an absence of the portal vein. The presence of either a gastrorenal or splenorenal shunt was evident in another 4 patients. Six patients had a history of hypergalactosemia with normal enzyme activities, as seen during neonatal screening. Six (66.7%) of the 9 patients were identified to have clinically significant pulmonary arterial hypertension (mean pulmonary artery pressure: 34-79 mm Hg; pulmonary vascular resistances: 5.12-38.07 U). The median age at the onset of pulmonary arterial hypertension was 12 years and 3 months. Histologic studies of lung specimens, which were available in 4 of the 9 patients with congenital portosystemic venous shunt, showed small arterial microthrombotic lesions in 3 patients. This characteristic finding was recognized even in the congenital portosystemic venous shunt patients without PAH. This study demonstrated thromboembolic pulmonary arterial hypertension to be a crucial complication in congenital portosystemic venous shunt, and this pathologic state may be latently present in patients with pulmonary arterial hypertension of unknown etiology.