Stability of a rat model of prehepatic portal hypertension caused by partial ligation of the portal vein

2009 ◽  
Vol 15 (32) ◽  
pp. 3449
Author(s):  
Zhe Wen ◽  
Jin-Zhe Zhang ◽  
Hui-Min Xia ◽  
Chun-Xiao Yang ◽  
Ya-Jun Chen
Keyword(s):  
Portal Hypertension ◽  
Portal Vein ◽  
Rat Model

Evolution of portal hypertension and mechanisms involved in its maintenance in a rat model

1985 ◽  
Vol 248 (6) ◽  
pp. G618-G625 ◽  
Author(s):  
E. Sikuler ◽  
D. Kravetz ◽  
R. J. Groszmann
Keyword(s):  
Blood Flow ◽  
Portal Hypertension ◽  
Portal Vein ◽  
Rat Model ◽  
Portal Pressure ◽  
Portal System ◽  
Hypertensive Rats ◽  
Hemodynamic Changes ◽  
Sequence Of Events ◽  
Radioactive Microsphere

In rats with portal hypertension induced by partial ligation of the portal vein, we have recently demonstrated an increased portal venous inflow that becomes an important factor in the maintenance of portal hypertension. The sequence of events that leads into this circulatory disarray is unknown. We evaluated chronologically the chain of hemodynamic changes that occurred after portal hypertension was induced by partial ligation of the portal vein. In this model it is possible to follow, from the initiation of the portal-hypertensive state, the interaction between blood flow and resistance in the portal system as well as the relation between the development of portal-systemic shunting and the elevated portal venous inflow. The study was performed in 45 portal-hypertensive rats and in 29 sham-operated rats. Blood flow and portal-systemic shunting were measured by radioactive microsphere techniques. The constriction of the portal vein was immediately followed by a resistance-induced portal hypertension characterized by increased portal resistance (9.78 +/- 0.89 vs. 4.18 +/- 0.71 dyn X s X cm-5 X 10(4), mean +/- SE, P less than 0.01), increased portal pressure (17.7 +/- 0.9 vs. 9.5 +/- 0.6 mmHg, P less than 0.001), and decreased portal venous inflow (3.93 +/- 0.26 vs. 6.82 +/- 0.49 ml X min-1 X 100 g body wt-1, P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Interaction of flow and resistance in maintenance of portal hypertension in a rat model

1986 ◽  
Vol 250 (2) ◽  
pp. G205-G212 ◽  
Author(s):  
E. Sikuler ◽  
R. J. Groszmann
Keyword(s):  
Portal Hypertension ◽  
Portal Vein ◽  
Rat Model ◽  
Portal Pressure ◽  
Flow Theory ◽  
Sham Operation ◽  
Portal Flow ◽  
Hemodynamic Changes ◽  
Forward Flow ◽  
Arteriolar Resistance

To clarify the roles that portocollateral resistance ("backward-flow" theory) and portal flow ("forward-flow" theory) play in maintaining chronic portal hypertension, we studied, in a rat model with prehepatic portal hypertension, the hemodynamic changes that occur when portocollateral resistance is reduced and high portal venous inflow is maintained. In 30 portal-hypertensive rats the constriction around the portal vein was removed 4 days after induction of portal hypertension, 30 rats were used as portal vein-constricted controls, and 30 additional rats were subjected to a sham operation. The removal of the ligature constricting the portal vein was followed by an immediate decrease in portal pressure (from 16.3 +/- 0.8 to 9.6 +/- 0.8 mmHg, P less than 0.001). Two days after the ligature removal, hyperdynamic circulation was still evident and was characterized by a decreased splanchnic arteriolar resistance and an increased portal venous inflow. The coexistence of high portal venous inflow and normal portal pressure indicates that high portal venous inflow per se is not sufficient to produce an increase in portal pressure when it faces a low-resistance vascular bed. We conclude that portal hypertension is induced by the interaction of an abnormally high portal venous inflow and high resistance offered to the flow by the portocollateral vessels. Neither the forward-flow theory nor the backward-flow theory can be applied solely to explain the increased portal pressure.

Aminoguanidine ameliorates splanchnic hyposensitivity to glypressin in a haemorrhage-transfused rat model of portal hypertension

1998 ◽  
Vol 95 (5) ◽  
pp. 629-636 ◽  
Author(s):  
Chi-Jen CHU ◽  
Fa-Yauh LEE ◽  
Sun-Sang WANG ◽  
Full-Young CHANG ◽  
Han-Chieh LIN ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Portal Hypertension ◽  
Mean Arterial Pressure ◽  
Arterial Pressure ◽  
Portal Vein ◽  
Rat Model ◽  
Portal Pressure ◽  
Hypotensive Effect ◽  
Portal Vein Ligation ◽  
Nitric Oxide Synthase Inhibitor

1.Hyposensitivity to vasopressin is a well-documented phenomenon in animals with portal hypertension and patients with cirrhosis subjected to haemorrhage. Excessive formation of nitric oxide is at least partly responsible for the vascular hyporesponsiveness to vasoconstrictors observed in experimental portal hypertension or in rats with haemorrhagic shock. This study investigated whether addition of aminoguanidine, a preferential inducible nitric oxide synthase inhibitor, to glypressin (a long-acting vasopressin analogue) could enhance its portal hypotensive effect in portal-hypertensive rats with bleeding. 2.Portal hypertension was induced by partial portal vein ligation. Fourteen days after operation, systemic and portal haemodynamics were measured in stable or bleeding portal vein-ligated rats receiving intravenous glypressin (0.07 ;mg/kg) or aminoguanidine (70 ;mg/kg) followed by glypressin infusion. In rats with a hypotensive haemorrhage, 4.5 ;ml of blood was withdrawn and 50% of the withdrawn blood was reinfused before the administration of glypressin or aminoguanidine. 3.Glypressin resulted in a significantly greater decrease in portal pressure in portal vein-ligated rats without bleeding than in those with bleeding (P< 0.001). In contrast, glypressin induced similar changes in mean arterial pressure between the two groups (P> 0.05). The addition of aminoguanidine significantly potentiated the portal-hypotensive effect of glypressin in bleeding portal vein-ligated rats (P< 0.005) without an effect on the changes in mean arterial pressure induced by glypressin infusion (P> 0.05). 4.Splanchnic hyposensitivity to glypressin exists in a haemorrhage-transfused rat model of portal hypertension. This hyposensitivity can be ameliorated by the administration of aminoguanidine.

scholarly journals Effect of Fluid Shear Stress on Portal Vein Remodeling in a Rat Model of Portal Hypertension

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Bin Wen ◽  
Jian Liang ◽  
Xin Deng ◽  
Ran Chen ◽  
Peichun Peng
Keyword(s):  
Electron Microscopy ◽  
Shear Stress ◽  
Portal Hypertension ◽  
Portal Vein ◽  
Rat Model ◽  
Fluid Shear Stress ◽  
Membrane Integrity ◽  
Control Group ◽  
Fluid Shear ◽  
Cell Degeneration

Aims. To explore the effects and mechanisms of fluid shear stress on portal vein remodeling in a rat model of portal hypertension.Methods. Subcutaneous injections of CCl4 were given to establish a rat model of liver cirrhosis and portal hypertension. Biomechanical technology was adopted to determine the dynamic changes of haemodynamic indices and fluid shear stress. Nitric oxide (NO), synthase (NOS), and endothelin-1 (ET-1) of the portal vein blood were measured. Changes in geometric structure and ultrastructure of the portal vein were observed using optical and electron microscopy.Results. After the CC14 injections, rat haemodynamics were notably altered. From week 4 onwards, PVP, PVF, and PVR gradually and significantly increased (P<0.05versus baseline). The fluid shear stress declined from week 4 onwards (P<0.01versus control group). NO, NOS, and ET-1 increased after repeated CCI4 injections. Hematoxylin and eosin staining showed thickened portal vein walls, with increased inside and outside diameters. Electron microscopy revealed different degrees of endothelial cell degeneration, destruction of basement membrane integrity, proliferating, and hypertrophic smooth muscle cells.Conclusions. Fluid shear stress not only influenced the biomechanical environment of the portal vein but also participated in vascular remodeling.

Novel rat model of repetitive portal venous embolization mimicing human non-cirrhotic idiopathic portal hypertension

2016 ◽  
Vol 54 (08) ◽  
Author(s):  
S Klein ◽  
C Hinüber ◽  
K Hittatiya ◽  
R Schierwagen ◽  
FE Uschner ◽  
...  
Keyword(s):  
Portal Hypertension ◽  
Rat Model ◽  
Idiopathic Portal Hypertension

scholarly journals Stent patency and outcome of TIPS through the left versus the right portal branches

2020 ◽  
Vol 51 (1) ◽  
Author(s):  
Mohamed S. Alwarraky ◽  
Hasan A. Elzohary ◽  
Mohamed A. Melegy ◽  
Anwar Mohamed
Keyword(s):  
Portal Hypertension ◽  
Clinical Outcome ◽  
Portal Vein ◽  
Variceal Bleeding ◽  
Patency Rate ◽  
Hospital Admissions ◽  
Stent Patency ◽  
Left Branch ◽  
The Right

Abstract Background Our purpose is to compare the stent patency and clinical outcome of trans-jugular intra-hepatic porto-systemic shunt (TIPS) through the left branch portal vein (TIPS-LPV) to the standard TIPS through the right branch (TIPS-RPV). We retrospectively reviewed all patients (n = 54) with refractory portal hypertension who were subjected to TIPS-LPV at our institute (TIPS-LPV) between 2016 and 2018. These patients were matched with 56 control patients treated with the standard TIPS-RPV (TIPS-RPV). The 2 groups were compared regarding the stent patency rate, encephalopathy, and re-interventions for 1 year after the procedure. Results TIPS-LPV group showed 12 months higher patency rate (90.7% compared to 73.2%) (P < 0.005). The number of the encephalopathy attacks in the TIPS-LPV group was significantly lower than that of the TIPS-RPV group at 6 and 12 months of follow-up [P = 0.012 and 0.036, respectively]. Re-bleeding and improvement of ascites were the same in the two groups [P > 0.05]. Patients underwent TIPS-LPV needed less re-interventions and required less hospitalizations than those with TIPS-RPV [P = 0.039 and P = 0.03, respectively]. Conclusion The new TIPS approach is to extend the stent to LPV. This new TIPS-LPV approach showed the same clinical efficiency as the standard TIPS-RPV in treating variceal bleeding and ascites. However, it proved a better stent patency with lower rates of re-interventions, encephalopathy, and hospital admissions than TIPS through the right branch.

scholarly journals A comparative study of multi-detector CT portography versus endoscopy in evaluation of gastro-esophageal varices in portal hypertension patients

2020 ◽  
Vol 51 (1) ◽  
Author(s):  
Hany El-Assaly ◽  
Lamiaa I. A. Metwally ◽  
Heba Azzam ◽  
Mohamed Ibrahim Seif-Elnasr
Keyword(s):  
Portal Hypertension ◽  
Portal Vein ◽  
Esophageal Varices ◽  
Imaging Modality ◽  
Splenic Vein ◽  
Gastric Varices ◽  
Gi Endoscopy ◽  
Upper Gi ◽  
Upper Gi Endoscopy ◽  
Vein Diameter

Abstract Background Portal hypertension is a major complication resulting from obstruction of portal blood flow, like cirrhosis or portal vein thrombosis, that leads to portal hypertension. MDCT angiography has become an important tool for investigation of the liver as well as potentially challenging varices by detailing the course of these tortuous vessels. This information is decisive for liver transplantation as well as for common procedures in which an unexpected varix can cause significant bleeding. Results This study included an assessment of 60 cases of portal hypertension (28 males and 32 females), their age ranged from 42 to 69 years (mean age = 57.2 ± 6.63). All patients were diagnosed with portal hypertension, underwent upper GI endoscopy followed by a triphasic CT scan with CT angiographic assessment for the screening of gastro-esophageal varices. CT is highly sensitive as compared to upper GI endoscopy (sensitivity 93%) in detecting esophageal varices. Gastric varices detected by CT in 22 patients (37%) compared to 14 patients (23%) detected by endoscopy. While paraesophageal varices were detected in 63% of patients and retro-gastric varices in 80% of patients that were not visualized by endoscopy. Our study reported that the commonest type of collaterals were the splenic collaterals, and we also found there is a significant correlation between the portal vein diameter and the number of collaterals as well as between the portal vein diameter and splenic vein diameter. Conclusions Multi-slice CT serves as an important non-invasive imaging modality in the diagnosis of collaterals in cases of portal hypertension. CT portography can replace endoscopy in the detection of high-risk varices. It also proved that there is a correlation between portal vein diameter, splenic vein diameter, and number of collaterals.

scholarly journals Multidisciplinary treatment of left hepatic artery pseudoaneurysm after hepatobiliary resection for gallbladder cancer: a case report

2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Ryusei Yamamoto ◽  
Teiichi Sugiura ◽  
Yukiyasu Okamura ◽  
Takaaki Ito ◽  
Yusuke Yamamoto ◽  
...  
Keyword(s):  
Portal Hypertension ◽  
Portal Vein ◽  
Liver Failure ◽  
Hepatic Artery ◽  
Remnant Liver ◽  
Left Hepatic Artery ◽  
Artery Pseudoaneurysm ◽  
Hepatobiliary Resection ◽  
Portal Vein Arterialization ◽  
Arterial Inflow

Abstract Background When a postoperative hepatic artery pseudoaneurysm develops after massive hepatectomy, both an intervention for the pseudoaneurysm and patency of hepatic artery should be considered because occlusion of the residual hepatic artery results in critical liver failure. However, the treatment strategy for a pseudoaneurysm of the hepatic artery after hepatobiliary resection is not well established. Case presentation A 65-year-old woman underwent right hepatectomy, extrahepatic duct resection, and portal vein resection, for gallbladder cancer. Although the patient had an uneventful postoperative course, computed tomography on postoperative day 6 showed a 6-mm pseudoaneurysm of the hepatic artery. Angiography revealed the pseudoaneurysm located on the bifurcation of the left hepatic artery to the segment 2 artery plus the segment 3 artery and 4 artery. Stent placement in the left hepatic artery was not feasible because the artery was too narrow, and coiling of the pseudoaneurysm was associated with a risk of occluding the left hepatic artery and inducing critical liver failure. Therefore, portal vein arterialization constructed by anastomosing the ileocecal artery and vein was performed prior to embolization of the pseudoaneurysm to maintain the oxygen level of the remnant liver, even if the left hepatic artery was accidentally occluded. The pseudoaneurysm was selectively embolized without occlusion of the left hepatic artery, and the postoperative laboratory data were within normal limits. Although uncontrollable ascites due to portal hypertension occurred, embolization of the ileocolic shunt rapidly resolved it. The patient was discharged on postoperative day 45. Conclusion Portal vein arterialization prior to embolization of the aneurysm may be a feasible therapeutic strategy for a pseudoaneurysm that develops after hepatectomy for hepatobiliary malignancy to guarantee arterial inflow to the remnant liver. Early embolization of arterioportal shunting after confirmation of arterial inflow to the liver should be performed to prevent morbidity induced by portal hypertension.

scholarly journals MesoTIPS: Combined Approach for the Treatment of Portal Hypertension Secondary to Portal Vein Thrombosis – A Brief Report

2017 ◽  
Vol 01 (01) ◽  
pp. 20-26
Author(s):  
Abbas Chamsuddin ◽  
Lama Nazzal ◽  
Thomas Heffron ◽  
Osama Gaber ◽  
Raja Achou ◽  
...  
Keyword(s):  
Portal Hypertension ◽  
Portal Vein ◽  
Portal Vein Thrombosis ◽  
Transjugular Intrahepatic Portosystemic Shunt ◽  
Portosystemic Shunt ◽  
Vein Thrombosis ◽  
Intrahepatic Portosystemic Shunt ◽  
The Right ◽  
Minilaparotomy Approach ◽  
Mean Time

AbstractIntroduction: We describe a technique we call “Meso-transjugular intrahepatic portosystemic shunt (MTIPS)” for relief of portal hypertension secondary to portal vein thrombosis (PVT) using combined surgical and endovascular technique. Materials and Methods: Nine adult patients with PVT underwent transjugular intrahepatic portosystemic shunt through a combined transjugular and mesenteric approach (MTIPS), in which a peripheral mesenteric vein was exposed through a minilaparotomy approach. The right hepatic vein was accessed through a transjugular approach. Mechanical thrombectomy, thrombolysis, and angioplasty were performed when feasible to clear PVT. Results: All patients had technically successful procedures. Patients were followed up for a mean time of 13.3 months (range: 8 days to 3 years). All patients are still alive and asymptomatic. Conclusion: We conclude that MTIPS is effective for the relief of portal hypertension secondary to PVT.

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