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Bosch J, Iwakiri Y. The portal hypertension syndrome: etiology, classification, relevance, and animal models. Hepatol Int 2017; 12:1-10. [PMID: 29064029 DOI: 10.1007/s12072-017-9827-9] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 09/26/2017] [Indexed: 12/20/2022]
Abstract
BACKGROUND Portal hypertension is a key complication of portal hypertension, which is responsible for the development of varices, ascites, bleeding, and hepatic encephalopathy, which, in turn, cause a high mortality and requirement for liver transplantation. AIM This review deals with the present day state-of-the-art preventative treatments of portal hypertension in cirrhosis according to disease stage. Two main disease stages are considered, compensated and decompensated cirrhosis, the first having good prognosis and being mostly asymptomatic, and the second being heralded by the appearance of bleeding or non-bleeding complications of portal hypertension. RESULTS The aim of treatment in compensated cirrhosis is preventing clinical decompensation, the more frequent event being ascites, followed by variceal bleeding and hepatic encephalopathy. Complications are mainly driven by an increase of hepatic vein pressure gradient (HVPG) to values ≥10 mmHg (defining the presence of Clinically Significant Portal Hypertension, CSPH). Before CSPH, the treatment is limited to etiologic treatment of cirrhosis and healthy life style (abstain from alcohol, avoid/correct obesity…). When CSPH is present, association of a non-selective beta-blocker (NSBB), including carvedilol should be considered. NSBBs are mandatory if moderate/large varices are present. Patients should also enter a screening program for hepatocellular carcinoma. In decompensated patients, the goal is to prevent further bleeding if the only manifestation of decompensation was a bleeding episode, but to prevent liver transplantation and death in the common scenario where patients have manifested first non-bleeding complications. Treatment is based on the same principles (healthy life style..) associated with administration of NSBBs in combination if possible with endoscopic band ligation if there has been variceal bleeding, and complemented with simvastatin administration (20-40 mg per day in Child-Pugh A/B, 10-20 mg in Child C). Recurrence shall be treated with TIPS. TIPS might be indicated earlier in patients with: 1) Difficult/refractory ascites, who are not the best candidates for NSBBs, 2) patients having bleed under NSBBs or showing no HVPG response (decrease in HVPG of at least 20% of baseline or to values equal or below 12 mmHg). Decompensated patients shall all be considered as potential candidates for liver transplantation. CONCLUSION Treatment of portal hypertension has markedly improved in recent years. The present day therapy is based on accurate risk stratification according to disease stage.
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Affiliation(s)
- Jaime Bosch
- Hepatic Hemodynamic Laboratory, Liver Unit, Hospital Clínic-IDIBAPS, University of Barcelona, C.Villarroel 170, 08036, Barcelona, Spain. .,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Instituto de Salud Carlos III, Barcelona, Spain. .,Swiss Liver Center, Hepatology, UVCM, Inselspital, University of Bern, Bern, Switzerland.
| | - Yasuko Iwakiri
- Section of Digestive Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, 06520, USA
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2
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Jaberi A, Toor SS, Rajan DK, Mironov O, Kachura JR, Cleary SP, Smoot R, Tremblay St-Germain A, Tan K. Comparison of Clinical Outcomes following Glue versus Polyvinyl Alcohol Portal Vein Embolization for Hypertrophy of the Future Liver Remnant prior to Right Hepatectomy. J Vasc Interv Radiol 2016; 27:1897-1905.e1. [PMID: 27435682 DOI: 10.1016/j.jvir.2016.05.023] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 05/01/2016] [Accepted: 05/18/2016] [Indexed: 12/21/2022] Open
Abstract
PURPOSE To report outcomes after portal vein embolization (PVE) and right hepatectomy in patients receiving embolization with N-butyl cyanoacrylate (NBCA) glue + central AMPLATZER Vascular Plug (AVP; glue group) or polyvinyl alcohol (PVA) particles ± coils (PVA group). MATERIALS AND METHODS Between March 2008 and August 2013, all patients having PVE with NBCA + AVP or PVA ± coils before right hepatectomy were retrospectively reviewed; 85 patients underwent PVE with NBCA + AVP (n = 45) or PVA ± coils (n = 40). The groups were compared using Mann-Whitney U and χ2 tests. RESULTS Technical success of embolization was 100%. Degree of hypertrophy (16.2% ± 7.8 vs 12.3% ± 7.62, P = .009) and kinetic growth rate (3.5%/wk ± 2.0 vs 2.6%/wk ± 1.9, P = .016) were greater in the glue group versus the PVA group. Contrast volume (66.1 mL ± 44.8 vs 189.87 mL ± 62.6, P < .001) and fluoroscopy time (11.2 min ± 7.8 vs 23.49 min ± 11.7, P < .001) were significantly less during the PVE procedure in the glue group. Surgical outcomes were comparable between groups, including the number of patients unable to go onto surgery (P = 1.0), surgical complications (P = .30), length of hospital stay (P = .68), and intensive care unit admissions (P = .71). There was 1 major complication (hepatic abscess) in each group after PVE. CONCLUSIONS PVE performed with NBCA + AVP compared with PVA ± coils resulted in greater degree of hypertrophy of the future liver remnant, less fluoroscopic time and contrast volume, and similar complication rates.
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Affiliation(s)
- Arash Jaberi
- Division of Vascular and Interventional Radiology, Toronto General Hospital-University Health Network/University of Toronto, Toronto, Ontario M5G2N2, Canada.
| | - Sundeep S Toor
- Department of Diagnostic Imaging , Markham Stouffville Hospital, Markham, Ontario, Canada
| | - Dheeraj K Rajan
- Division of Vascular and Interventional Radiology, Toronto General Hospital-University Health Network/University of Toronto, Toronto, Ontario M5G2N2, Canada
| | - Oleg Mironov
- Division of Vascular and Interventional Radiology, Toronto General Hospital-University Health Network/University of Toronto, Toronto, Ontario M5G2N2, Canada
| | - John R Kachura
- Division of Vascular and Interventional Radiology, Toronto General Hospital-University Health Network/University of Toronto, Toronto, Ontario M5G2N2, Canada
| | - Sean P Cleary
- Department of Medical Imaging, and Division of General Surgery, Department of Surgery, Toronto General Hospital-University Health Network/University of Toronto, Toronto, Ontario M5G2N2, Canada
| | - Rory Smoot
- Department of Medical Imaging, and Division of General Surgery, Department of Surgery, Toronto General Hospital-University Health Network/University of Toronto, Toronto, Ontario M5G2N2, Canada
| | - Amélie Tremblay St-Germain
- Department of Medical Imaging, and Division of General Surgery, Department of Surgery, Toronto General Hospital-University Health Network/University of Toronto, Toronto, Ontario M5G2N2, Canada
| | - Kongteng Tan
- Division of Vascular and Interventional Radiology, Toronto General Hospital-University Health Network/University of Toronto, Toronto, Ontario M5G2N2, Canada
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Geisel D, Malinowski M, Powerski MJ, Wüstefeld J, Heller V, Denecke T, Stockmann M, Gebauer B. Improved hypertrophy of future remnant liver after portal vein embolization with plugs, coils and particles. Cardiovasc Intervent Radiol 2013; 37:1251-8. [PMID: 24310828 DOI: 10.1007/s00270-013-0810-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 11/10/2013] [Indexed: 02/08/2023]
Abstract
PURPOSE To retrospectively analyze efficacy as measured by volume gain of future remnant liver (FRL) after right portal vein embolization (PVE) using particles only versus particles and additional central plug and/or coil (CP/C) embolization. METHODS All patients who underwent PVE between July 2011 and December 2012 were retrospectively analyzed. Right PVE was performed either with particle-only (PO) embolization or additional CP/C embolization. All enrolled patients underwent computed tomography or magnetic resonance imaging before PVE and surgery. The images were used for volumetry of the FRL. RESULTS Of 75 patients, 40 had PO and 35 CP/C embolization. Age, sex, and tumor entities did not differ significantly between the two groups. Tumor entities included cholangiocarcinoma (n = 52), metastasis from colorectal cancer (n = 14), hepatocellular carcinoma (n = 2), and others (n = 7). Time from PVE to preoperative imaging was similar in both groups. FRL volume before PVE was 329 ± 121 ml in the PO group and 333 ± 135 ml in the CP/C group, and 419 ± 135 ml and 492 ± 165 ml before operation. The average percentage volume gain was significantly higher in the CP/C group than in the PO group, with 53.3 ± 34.5 % versus 30.9 ± 28.8 % (p = 0.002). CONCLUSION Right PVE with additional CP/C embolization leads to a significantly higher gain in FRL volume than embolization with particles alone.
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Affiliation(s)
- Dominik Geisel
- Department of Diagnostic and Interventional Radiology, Charité, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany,
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Link TW, Woodrum D, Gilson WD, Pan L, Qian D, Kraitchman DL, Bulte JWM, Arepally A, Weiss CR. MR-guided portal vein delivery and monitoring of magnetocapsules: assessment of physiologic effects on the liver. J Vasc Interv Radiol 2011; 22:1335-40. [PMID: 21816623 DOI: 10.1016/j.jvir.2011.03.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Revised: 03/11/2011] [Accepted: 03/15/2011] [Indexed: 11/28/2022] Open
Abstract
PURPOSE The authors previously developed magnetic resonance (MR)-trackable magnetocapsules (MCs) that can simultaneously immunoprotect human islet cells and noninvasively monitor portal delivery and engraftment in real time with MR imaging. This study was designed to assess the physiologic effects of the delivery of a clinical dose of MCs (140,000 capsules) into the portal vein (PV) in swine over a 1-month period. MATERIALS AND METHODS MCs were formed by using clinical-grade alginate mixed with a clinically applicable dosage of ferumoxide. Percutaneous access into the PV was obtained by using a custom-built, MR-trackable needle, and 140,000 MCs were delivered under MR guidance in five swine. Portal pressures and liver function data were obtained over a 4-week period. RESULTS A transient increase in portal pressure occurred immediately after MC delivery that returned to normal levels by 4 weeks after MC delivery. Liver function test results were normal during the entire period, and the appearance of the MCs on MR imaging did not change. CONCLUSIONS A clinically applicable dose of 140,000 MCs has no adverse effects on portal pressures or liver function in this normal swine model during the first month after delivery.
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Affiliation(s)
- Thomas W Link
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Avritscher R, Wright KC, Javadi S, Uthamanthil R, Gupta S, Gagea M, Bassett RL, Murthy R, Wallace MJ, Madoff DC. Development of a large animal model of cirrhosis and portal hypertension using hepatic transarterial embolization: a study in swine. J Vasc Interv Radiol 2011; 22:1329-34. [PMID: 21802316 DOI: 10.1016/j.jvir.2011.04.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Revised: 04/19/2011] [Accepted: 04/21/2011] [Indexed: 12/13/2022] Open
Abstract
PURPOSE To develop a clinically relevant porcine model of liver cirrhosis with portal hypertension by means of hepatic transarterial embolization. MATERIALS AND METHODS Institutional animal care and use committee approval was obtained for all experiments. Pigs received transcatheter arterial infusion of a 3:1 mixture of iodized oil and ethanol into the hepatic artery in volumes of 16 mL in group 1 (n = 4), 28 mL in group 2 (n = 4), and 40 mL in group 3 (n = 4) with intent of bilobar distribution. Hepatic venous pressure gradient (HVPG) measurement, liver function tests, and volumetry were performed at baseline, at 2 weeks, and before necropsy. RESULTS Cirrhosis was successfully induced in three animals that received 16 mL of the embolic mixture and in all four animals that received 28 mL. The animals in the 40-mL group did not recover from the procedure and were euthanized within 48 h. Increases in HVPG after 6-8 weeks versus baseline reached statistical significance (P < .05). Correlation between degree of fibrosis and volume of embolic agent did not reach statistical significance, but there was a trend toward increased fibrosis in the 28-mL group compared with the 16-mL group. CONCLUSIONS Transcatheter hepatic arterial embolization can be used to create a reliable and reproducible porcine model of liver cirrhosis and portal hypertension.
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Affiliation(s)
- Rony Avritscher
- Department of Diagnostic Radiology, Interventional Radiology Section, University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA
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Portal Vein Embolization with Radiolabeled Polyvinyl Alcohol Particles in a Swine Model: Hepatic Distribution and Implications for Pancreatic Islet Cell Transplantation. Cardiovasc Intervent Radiol 2009; 32:499-507. [DOI: 10.1007/s00270-009-9544-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2008] [Revised: 01/13/2009] [Accepted: 01/28/2009] [Indexed: 11/26/2022]
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Yoo H, Ko GY, Gwon DI, Kim JH, Yoon HK, Sung KB, Kim N, Lee J. Preoperative portal vein embolization using an amplatzer vascular plug. Eur Radiol 2008; 19:1054-61. [PMID: 19057904 DOI: 10.1007/s00330-008-1240-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2008] [Revised: 10/01/2008] [Accepted: 10/05/2008] [Indexed: 12/16/2022]
Abstract
The purpose was to evaluate the safety and efficacy of preoperative portal vein embolization (PVE) using an Amplatzer vascular plug (AVP). Forty-one patients who underwent PVE using gelatin sponge particles and the AVP were enrolled. The right portal branches were embolized using gelatin sponges (1-8 mm(3)) through a 5-F catheter, and the AVP was deployed at the first- or second-order right portal vein. Technical success and complications, recanalization, and changes of total estimated liver volumes (TELV), future liver remnant (FLR), and FLR/TELV were evaluated. Follow-up CT performed 6-43 days (median, 16 days) after PVE was used to evaluate volume parameters. PVE was technically successful in 40 of 41 patients. Major complications occurred in two patients, with one each having extensive portal vein thrombosis and liver abscess. Partial recanalization of the occluded portal vein was seen in one patient. The mean FLR volume (653 +/- 174 ml vs. 532 +/- 154 ml, p < 0.001) and mean FLR/TELV ratio (43 +/- 8% vs 36 +/- 7%, p < 0.001) were significantly higher after than before PVE. PVE using the AVP seems to be a relatively safe and effective technique for inducing hypertrophy of the FLR with minimal risk of recanalization.
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Affiliation(s)
- Hyunkyung Yoo
- Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
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8
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Park JS, Oh JH, Kim DY, Park YK, Park SJ, Kim SJ. Effects of intraluminal irradiation with Holmium-166 for TIPS stenosis: experimental study in a swine model. Korean J Radiol 2007; 8:127-35. [PMID: 17420630 PMCID: PMC2626774 DOI: 10.3348/kjr.2007.8.2.127] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
OBJECTIVE We wanted to evaluate the effectiveness of intraluminal irradiation with Holmium-166 ((166)Ho) for reducing the pseudointimal hyperplasia (PIH) in the transjugular intrahepatic portosystemic shunt (TIPS) tract in a swine model. MATERIALS AND METHODS TIPS was performed in 12 domestic pigs, after the creation of portal hypertension by intraportal injection of a mixture of N-butyl-2-cyanoacrylate (NBCA) and lipiodol. Five pigs first underwent intraluminal irradiation (30 Gy) in the parenchymal tract with using a (166)Ho solution-filled balloon catheter, and this was followed by the placement of a nitinol stent in the TIPS tract. For the seven control pigs, the balloon was filled with saline and contrast media mixture. Two weeks later, follow-up portography and histological analysis were performed. RESULTS TIPS was successfully performed in all twelve pigs with achieving artificially induced portal hypertension. Portography performed two weeks after TIPS showed the patent tracts in the TIPS tracts that were irradiated with (166)Ho (5/5, 100%), whereas either completely (5/6, 83.3%) or partially (1/6, 16.7%) occluded TIPS were seen in the seven pigs of the nonirradiated control group, except in one pig that experienced periprocedural death due to bleeding. Histological analysis showed a statistically significant difference for the maximal PIH (irradiated: 32.8%, nonirradiated: 76.0%, p < 0.001) between the two groups. CONCLUSION Intraluminal irradiation with 30 Gy of (166)Ho for TIPS significantly improved the TIPS patency in a swine model of portal hypertension during a 2-week period of follow-up.
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Affiliation(s)
- Ji Seon Park
- Department of Diagnostic Radiology, Kyung Hee University Medical Center, Seoul 130-702, Korea
| | - Joo Hyeong Oh
- Department of Diagnostic Radiology, Kyung Hee University Medical Center, Seoul 130-702, Korea
| | - Deog Yoon Kim
- Department of Nuclear Medicine, Kyung Hee University Medical Center, Seoul 130-702, Korea
| | - Yong Koo Park
- Department of Pathology, Kyung Hee University Medical Center, Seoul 130-702, Korea
| | - Sang Joon Park
- Department of Diagnostic Radiology, Kang Dong Sacred Heart Hospital, Hallym University, Seoul 134-010, Korea
| | - Soo Joong Kim
- Department of Cardiology, Kyung Hee University Medical Center, Seoul 130-702, Korea
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Shamiyeh A, Hubmann R, Benkö L, Vattay P, Röth E, Tulipan L, Wayand WU, Danis J. Laparoscopic Azygoportal Disconnection Procedure with a Bipolar Feedback Controlled Sealing System in a Porcine Model1. J Surg Res 2006; 130:8-12. [PMID: 16289598 DOI: 10.1016/j.jss.2005.07.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2004] [Revised: 07/02/2005] [Accepted: 07/23/2005] [Indexed: 11/23/2022]
Abstract
BACKGROUND To examine the feasibility of a new, minimally invasive procedure for the devascularization of the proximal stomach and distal esophagus to prevent recurrent variceal bleeding in portal hypertension in a new animal model. MATERIAL AND METHODS Portal hypertension was created by laparoscopic clip ligation of the portal vein on 20 pigs. After 2 weeks the azygoportal disconnection procedure was performed with the LigaSure-ATLAS instrument. RESULTS There were 16 pigs out of 20 that survived both operations. Two died during introduction of anesthesia, one because of a cardiac arrest (second operation). One pig died resulting from necrosis of the gastric and esophageal wall. Autopsy (2 weeks later) showed that there was a complete arterial devascularization. At autopsy, none of the remaining 16 pigs had esophageal varices or necrosis of the stomach or esophagus. CONCLUSION Laparoscopic azygoportal disconnection is a less invasive method for the prevention of rebleeding and seems to be safely performed with the LigaSure-ATLAS instrument.
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Affiliation(s)
- A Shamiyeh
- Ludwig Boltzmann Research Institute for Operative Laparoscopy and 2nd Surgical Department, Academic Teaching Hospital, Linz, Austria.
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10
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Lai L, Poneros J, Santilli J, Brugge W. EUS-guided portal vein catheterization and pressure measurement in an animal model: a pilot study of feasibility. Gastrointest Endosc 2004; 59:280-3. [PMID: 14745408 DOI: 10.1016/s0016-5107(03)02544-6] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND The extrahepatic portal vein is inaccessible to direct catheterization. METHODS Because EUS can readily image the portal vein, the feasibility of EUS-guided portal vein catheterization by using a 22-gauge needle was studied in 7 normal pigs and 14 pigs in which portal hypertension was induced (7/14 anticoagulated). RESULTS Catheterization was not possible by EUS or transhepatic methods in, respectively, 3 and 5 animals. One anticoagulated animal had a small amount of periduodenal bleeding as a result of EUS catheterization. The mean normal portal vein pressure (1 standard deviation) as determined by EUS and transhepatic methods was, respectively, 20.3 (4) mm Hg and 20.4 (2) mm Hg. Injection of polyvinyl alcohol particles increased the portal vein pressure by 10.2 (11.59) mm Hg. There was a close correlation under all conditions between the mean portal vein pressures obtained by EUS and transhepatic catheterization (r=0.91). CONCLUSIONS EUS-guided portal vein catheterization appears to be feasible in an animal model and provides accurate pressure measurements.
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Affiliation(s)
- Lawrence Lai
- Caritas Medical Center Hong Kong, Brigham and Women's Hospital, Vascular Radiology and GI Unit, Massachusetts General Hospital, Boston 02114, USA
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11
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Zhuang ZW, Hoopes PJ, Koutras PC, Ebbighausen WH, Wagner RJ, Bettmann MA. Transjugular intrahepatic portosystemic shunt with an autologous vein-covered stent: results in a swine model. J Vasc Interv Radiol 2001; 12:1333-42. [PMID: 11698634 DOI: 10.1016/s1051-0443(07)61560-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
PURPOSE To investigate the feasibility, safety, and efficacy of an autologous vein-covered stent (AVCS) to prevent shunt stenosis in a porcine transjugular intrahepatic portosystemic shunt (TIPS) model. MATERIALS AND METHODS TIPS were created with an AVCS in 12 healthy domestic swine and with a bare stent in 10 additional swine. Tissue response was compared with use of venography, histology, and computerized morphometry analysis 2 weeks after implantation. Differences between AVCS and noncovered stents (established by a t-test), as well as regional differences within a single stent (established by an f test), were considered significant at P <.05. RESULTS Twenty of 22 TIPS procedures were technically successful. Ten of 12 shunts with an AVCS (83%) and two of 10 with bare stents (20%) remained patent (<50% diameter narrowing) at euthanasia 2 weeks later (P <.01). Histologic evaluation of harvested bare stents showed marked intimal hyperplasia (IH), composed of smooth muscle cells, myofibroblasts, and fibroblasts. In contrast, the AVCS were remarkably free of IH and thromboses. In patent TIPS in both groups, endothelial coverage of the luminal surface was present histologically. IH accounted for 57% (26.27/45.79) of total stent cross-sectional lumen area in the control group and 21% (8.34/39.54) in the AVCS group (P <.01), with no intrashunt differences (P >.05). CONCLUSION Based on short-term follow-up, AVCS significantly improved TIPS patency by prevention of both IH and in-stent thrombosis. TIPS created with an AVCS was feasible and safe in our porcine model.
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Affiliation(s)
- Z W Zhuang
- Department of Radiology, Dartmouth-Hitchcock Medical Center, One Medical Center Drive, Lebanon, New Hampshire 03756, USA
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Braun U, Koller-Wild K, Bettschart-Wolfensberger R. Ultrasound-guided percutaneous portocentesis in 21 cows. Vet Rec 2000; 147:623-6. [PMID: 11128075 DOI: 10.1136/vr.147.22.623] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
An ultrasound-guided portocentesis was performed in 21 clinically healthy cows, and blood was collected for haematological, biochemical and blood-gas analyses. At the same time blood samples were collected from the left jugular vein of each cow for the same analyses. Immediately after the centesis, portal blood pressure was measured. The cows were examined daily thereafter for eight days and then slaughtered for postmortem examination of the internal organs. The mean (sd) portal blood pressure was 37.1 (5.47) mmHg, and ranged from 24 to 49 mmHg. There were small but significant differences between many of the haematological and biochemical parameters in jugular and portal blood, and the concentration of bile acids was on average 2.7 times higher, and the concentration of ammonia was 19.3 times higher in portal blood. The demeanour and behaviour of the cows, and their appetite and rectal temperature remained normal during the eight-day observation period. The haematocrit, total and differential leucocyte counts, and the concentrations of total solids and fibrinogen were not affected by portocentesis. On postmortem examination, no lesions were apparent in the peritoneum, liver and portal vein.
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Affiliation(s)
- U Braun
- Clinic of Veterinary Internal Medicine, University of Zurich, Switzerland
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13
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Haskal ZJ. Will Stent-Grafts Prolong TIPS Patency? J Vasc Interv Radiol 2000. [DOI: 10.1016/s1051-0443(00)70080-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Transjugular Intrahepatic Shunt Stenosis and Thrombosis: Shunt Biology and Stent-Grafts. PORTAL HYPERTENSION 2000. [DOI: 10.1007/978-3-642-57116-9_20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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15
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Haskal ZJ, Brennecke LH. Transjugular intrahepatic portosystemic shunts formed with polyethylene terephthalate-covered stents: experimental evaluation in pigs. Radiology 1999; 213:853-9. [PMID: 10580966 DOI: 10.1148/radiology.213.3.r99dc24853] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To evaluate the safety, efficacy, and tissue response associated with Wallstents covered with polyethylene terephthalate (PETP) compared with those associated with uncovered Wallstents for creation of transjugular intrahepatic portosystemic shunts (TIPS) in a porcine model. MATERIALS AND METHODS Thirteen TIPS were created in 13 minipigs: eight with PETP-covered Wallstents, five with standard Wallstents. Shunt venography was performed at 5-8 weeks, and necropsy was performed at 7-8 weeks. Histopathologic, immunohistochemical, and scanning electron microscopic examinations were performed. RESULTS Mean shunt stenoses of the control and graft groups were 45% and 53%, respectively. Graft stenoses involved the entire graft-bearing segment, whereas bare stent stenoses were localized within the liver tract. Myofibroblast and extracellular collagen matrix proliferation encompassed both control and graft-covered stents. There was one graft TIPS occlusion. One control TIPS stenosis was due to transstent proliferation of normal porcine hepatic tissue. A small focus of bile staining was seen on the abluminal surface of one TIPS, which was a patent PETP-lined shunt. CONCLUSION PETP graft TIPS provided equal, but not superior, patency to that of bare stent TIPS. The pattern of PETP TIPS graft healing differed from that of bare stents but was similar to that reported with other polyester graft vascular implants and consisted of diffuse transmural penetration and paving of the graft surface by extracellular collagen matrix and myofibroblasts.
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Affiliation(s)
- Z J Haskal
- Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, USA
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Lessie T, Yoon HC, Nelson HA, Fillmore DJ, Baldwin GN, Miller FJ. Intraluminal irradiation for TIPS stenosis: preliminary results in a swine model. J Vasc Interv Radiol 1999; 10:899-906. [PMID: 10435708 DOI: 10.1016/s1051-0443(99)70135-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
PURPOSE To evaluate the ability of 32phosphorus intraluminal irradiation to reduce pseudointimal hyperplasia in a transjugular intrahepatic portosystemic shunt (TIPS). MATERIALS AND METHODS TIPS were successfully placed in 11 swine with normal portal pressures. Six animals received 15.2 Gy intraluminal irradiation to the hepatic parenchyma and venous outflow tract at the time of TIPS placement with use of a NA32P-filled balloon angioplasty catheter. Five control animals underwent TIPS and balloon angioplasty with saline. All animals were followed up for 28 days, at which time percutaneous portography was performed, the animals were killed, and the tissue around the TIPS stent was processed for histologic analysis. Maximum pseudointimal hyperplasia as a percentage of estimated TIPS diameter was calculated for each animal. RESULTS At the time of euthanasia, all five control TIPS and all but one irradiated TIPS were occluded. Histologic analysis demonstrated considerable variability in the degree of pseudointimal hyperplasia within each TIPS and between animals. No statistically significant difference was found in the maximum pseudointimal hyperplasia, measured as a percentage of stent radius, between control (80.2%+/-17.4%) and irradiated animals (69.2%+/-25.2%). CONCLUSIONS Irradiation of TIPS with 15.2 Gy 32P delivered at the time of TIPS placement did not significantly improve TIPS patency or reduce the degree of pseudointimal hyperplasia in swine with normal portal pressures.
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Affiliation(s)
- T Lessie
- Department of Radiology, University of Utah School of Medicine, Salt Lake City 84132, USA
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Otal P, Rousseau H, Vinel JP, Ducoin H, Hassissene S, Joffre F. High occlusion rate in experimental transjugular intrahepatic portosystemic shunt created with a Dacron-covered nitinol stent. J Vasc Interv Radiol 1999; 10:183-8. [PMID: 10082107 DOI: 10.1016/s1051-0443(99)70463-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE To assess whether the use of a prosthesis covered by a Dacron sheath might prevent pseudointimal hyperplasia in a transjugular intrahepatic portosystemic shunt (TIPS). MATERIALS AND METHODS A TIPS procedure was performed in nine pigs, after creation of a portal vein microembolization model of portal hypertension, by using a Dacron-covered nitinol stent. The first centimeter on the lower extremity of this specially made prototype was uncovered, to avoid portal vein thrombosis. Three weeks later, the seven surviving animals underwent transjugular hemodynamic and angiographic follow-up and were then killed for gross and histologic evaluation. RESULTS Shunt insertion was possible in all pigs; two died of complications of the procedure. After 3 weeks only two shunts were patent, although a 50%-60% narrowing of the initial portion of the shunt was present; the remaining shunts were occluded. Histologic examination showed pseudointimal hyperplasia associated, in the cases of occlusion, with a luminal thrombosis. CONCLUSION This Dacron-covered stent did not prevent pseudointima formation over the stent and resulted in a high early occlusion rate, probably related to a pronounced tissue fibrotic response likely due to Dacron-induced inflammation.
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Affiliation(s)
- P Otal
- Department of Radiology, University Hospital of Toulouse Rangueil, Toulouse, France
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Duncan JR, Hicks ME, Cai SR, Brunt EM, Ponder KP. Embolization of portal vein branches induces hepatocyte replication in swine: a potential step in hepatic gene therapy. Radiology 1999; 210:467-77. [PMID: 10207431 DOI: 10.1148/radiology.210.2.r99fe10467] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
PURPOSE To determine whether embolization of portal vein branches would stimulate hepatocyte replication in pigs. MATERIALS AND METHODS The portal vein branches supplying 50%-70% of the liver were embolized in eight pigs by using a combination of coils and polyvinyl alcohol particles. The extent of embolization was assessed at portography in all animals and at computed tomography in one animal. Hepatocyte replication was determined by calculating the percentage of cells that incorporated bromodeoxyuridine into their nuclei. Animals survived up to 35 days after the procedure. RESULTS Embolization of the portal vein branches supplying the left and median lobes caused transient increases of less than 70% in portal vein pressures and of less than 100% in liver enzyme levels. Indocyanine green clearance was measured in two animals and decreased less than 50%. The percentage of replicating hepatocytes in the nonembolized lobe was 0% on day 0, 7% on day 2, 14% on day 7, and 2% on day 12. CONCLUSION Substantial hepatocyte replication occurred 2-7 days after embolization of portal vein branches. Further research will help determine if this procedure can facilitate retroviral transduction in large animals. If successful, the low morbidity of this method may allow its use in humans for gene therapy.
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Affiliation(s)
- J R Duncan
- Mallinckrodt Institute of Radiology, Washington Univ School of Medicine, St Louis, Mo., USA
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Teng GJ, Bettmann MA, Hoopes PJ, Ermeling BL, Yang L, Wagner RJ. Transjugular intrahepatic portosystemic shunt in a porcine model: histologic characteristics at the early stage. Acad Radiol 1998; 5:547-55. [PMID: 9702265 DOI: 10.1016/s1076-6332(98)80206-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
RATIONALE AND OBJECTIVES The authors attempted to determine the histologic processes that take place during development of stenosis after transjugular intrahepatic portosystemic shunt (TIPS) creation. MATERIALS AND METHODS TIPS were created with metallic stents in 20 healthy domestic pigs (tantalum stents in 10, stainless steel stents in 10). The animals were sacrificed 2-16 days later. All the shunts were examined by means of venography both immediately after placement of the stents and before sacrifice. All histologic sections were assessed with modified Giemsa and basic fuchsin stains. Anti-smooth-muscle-cell alpha-actin stain was used in three specimens. The stenotic reaction was quantified by using standard planimetry techniques and a computerized image-analysis system. RESULTS Within 16 days after TIPS placement, 15 (75%) of the 20 shunts were completely occluded, four (20%) of 20 shunts were partially occluded, and one (5%) of 20 shunts remained widely patent (animal died of unknown cause 2 days after the TIPS procedure). Stent occlusion was caused primarily by pseudointimal hyperplasia, which was similar morphologically in the portal, middle, and hepatic portions of the stent. Myofibroblastic proliferation was the most striking feature of the pseudointimal hyperplasia. The average thickness of the proliferation was 2.14 mm, which was 67% of the total diameter of the stent. A mild fibrous or lymphocytic reaction occurred around the stent wires and between the pseudointimal hyperplasia and the liver parenchyma. CONCLUSION The histologic features of pseudointimal formation in this swine TIPS model closely resemble those in humans. This model may prove useful for evaluating stents and other devices and improving the understanding of restenosis after vascular interventions.
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Affiliation(s)
- G J Teng
- Department of Radiology, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, USA
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