The role of TIPS for portal vein patency in liver transplant patients with portal vein thrombosis

Management of nonneoplastic portal vein thrombosis in the setting of liver transplantation: a systematic review

BACKGROUND

Nonneoplastic portal vein thrombosis (PVT) is frequent in patients with cirrhosis who undergo liver transplantation (LT); however, data on its impact on outcome and strategies of management are sparse.

METHODS

A systematic review of the literature was performed by analyzing studies that report on PVT in LT recipients and were published between January 1986 and January 2012.

RESULTS

Of 25,753 liver transplants, 2004 were performed in patients with PVT (7.78%), and approximately half presented complete thrombosis. Thrombectomy/thromboendovenectomy was employed in 75% of patients; other techniques included venous graft interposition and portocaval hemitransposition. Overall, the presence of PVT significantly increased 30-day (10.5%) and 1-year (18.8%) post-LT mortality when compared to patients without PVT (7.7% and 15.4%, respectively). However, only complete PVT accounted for this increased mortality. Rethrombosis occurred in up to 13% of patients with complete PVT and in whom no preventative strategies were used, and was associated with increased morbidity and mortality.

CONCLUSIONS

PVT is common in patients with cirrhosis undergoing LT, and it affects survival when it is complete, at least in the short term after transplant. Therefore, screening for this condition is essential, alongside adequate treatment strategies to attempt repermeation of the PV and prevent thrombosis extension.

Emergency anticoagulation treatment for cirrhosis patients with portal vein thrombosis and acute variceal bleeding

OBJECTIVE

To determine the safety and efficacy of anticoagulation treatment for portal vein thrombosis in cirrhosis patients with acute variceal bleeding, with patient eligibility determined by contrast ultrasonography findings.

MATERIALS AND METHODS

This prospective study included 23 consecutive cirrhosis patients (63.8 ± 11.8 years old, 12 males and 11 females) with emergency admission for acute variceal bleeding with or without portal vein thrombus. Eligibility for anticoagulation treatment was determined by positive intra-thrombus enhancement on contrast ultrasonography (perflubutane microbubble agent, 0.0075 mL/kg) performed before endoscopy. Low-molecular-weight heparin was administered after hemostasis was achieved by band ligation. Repeated band ligation or injection sclerotherapy combined with argon plasma coagulation was performed for variceal disappearance.

RESULTS

Hemostasis was achieved in all 10 patients with active bleeding. Five of these patients had portal vein thrombus, and all showed positive intra-thrombus enhancement on contrast ultrasonography. Anticoagulation treatment of these five patients resulted in complete recanalization of the portal vein within 2-11 days. There were no significant differences in the number of endoscopic treatment sessions or the length of hospital stay between the groups with and without thrombosis, and no complications including rebleeding were reported. Long term, none of the patients who continued oral anticoagulation treatment had recurrence of thrombosis (4/5). Variceal recurrence occurred only in the non-thrombosis group (2/18) during the follow-up period (median: 351 days).

CONCLUSIONS

Early anticoagulation treatment in cirrhosis patients with portal vein thrombosis and acute variceal bleeding may be safe, tolerated, and effective in cases with positive intra-thrombus enhancement on contrast ultrasonography.

Transjugular intrahepatic portosystemic shunt in the treatment of portal vein thrombosis: a critical review of literature

Reports of successful transjugular intrahepatic portosystemic shunt (TIPS) surgery in patients with portal vein thrombosis (PVT) are considered anecdotal owing to the technical difficulty of the procedure and potential procedure-related complications. A literature review was undertaken to determine the feasibility and safety of TIPS in the treatment of PVT. All studies in which TIPS was attempted in patients with PVT were identified by searching through the PUBMED and MEDLINE databases. A total of 424 PVT patients undergoing TIPS were reported in 54 articles. The success rate of TIPS insertion was 67-100% in 19 case series. Further, 85 patients with portal cavernoma underwent successful TIPS insertions. Three therapeutic strategies of TIPS placement were used: (1) TIPS placement followed by portal vein recanalization via the shunt, (2) portal vein recanalization via percutaneous approaches followed by TIPS placement, and (3) TIPS insertion between a hepatic vein and a large collateral vessel without portal vein recanalization. Four approaches were used to access the portal vein: transjugular, transhepatic, transsplenic, and transmesenteric. Intra-abdominal hemorrhage secondary to hepatic capsule perforation was lethal in only three patients. No episode of pulmonary embolism was reported. Other procedure-related complications were reversible. The overall incidence of shunt dysfunction and hepatic encephalopathy was 8-33% and 0-50%, respectively. In conclusion, the reviewed studies uniformly support the feasibility and safety of TIPS for PVT even in the presence of portal cavernoma. Further, several major issues that remain unresolved are discussed.

Hypercoagulability in cirrhosis: causes and consequences

Decreased levels of most coagulation factors and thrombocytopenia are the main haemostatic abnormalities of cirrhosis. As a consequence, this condition was, until recently, considered as the prototype acquired coagulopathy responsible for bleeding. However, recent evidence suggests that it should, rather, be regarded as a condition associated with normal or even increased thrombin generation. The bleeding events that occur in these patients should, therefore, be explained by the superimposed conditions that frequently occur in this setting. Due to elevated levels of factor VIII (procoagulant driver) in combination with decreased protein C (anticoagulant driver), which are typically found in patients with cirrhosis, a procoagulant imbalance, defined as a partial resistance to the in vitro anticoagulant action of thrombomodulin, can be demonstrated. Whether this in vitro hypercoagulability is truly representative of what occurs in vivo remains to be established. However, the hypothesis that it may have clinical consequences is attractive and deserves attention. The possible consequences that we discuss herein include whether (i) cirrhosis is a condition associated with increased risk of venous thromboembolism or portal vein thrombosis; (ii) the hypercoagulability associated with cirrhosis has any other role outside coagulation (i.e. progression of liver fibrosis); and (iii) anticoagulation should be used in cirrhosis. Although apparently provocative, considering anticoagulation as a therapeutic option in patients with cirrhosis is now supported by a rationale of increasing strength. There may be subgroups of patients who benefit from anticoagulation to treat or prevent thrombosis and to slow hepatic fibrosis. Clinical studies are warranted to explore these therapeutic options.

Transjugular intrahepatic portosystemic shunt for portal vein thrombosis with symptomatic portal hypertension in liver cirrhosis

BACKGROUND & AIMS

Data on the management of portal vein thrombosis (PVT) in patients with decompensated cirrhosis are extremely limited, particularly in the cases of the transjugular intrahepatic portosystemic shunt (TIPS). We assessed the outcome of TIPS for PVT in patients with cirrhosis and symptomatic portal hypertension and determined the predictors of technical success and survival.

METHODS

In the retrospective study, 57 consecutive patients receiving TIPS were enrolled between December 2001 and September 2008. All were diagnosed with chronic PVT, and 30 had portal cavernoma. Indications for TIPS were variceal hemorrhage (n = 56) and refractory ascites (n = 1).

RESULTS

TIPS were successfully placed in 75% of patients (43/57). The independent predictors of technical success included portal cavernoma, and the degree of thrombosis within the main portal vein (MPV), the portal vein branches, and the superior mesenteric vein. Only one patient died of severe procedure-related complication. The cumulative 1-year shunt dysfunction and hepatic encephalopathy rates were 21% and 25%, respectively. The cumulative 1- and 5-year variceal re-bleeding rates differed significantly between the TIPS success and failure groups (10% and 28% versus 43% and 100%, respectively; p = 0.0004), while the cumulative 1- and 5-year survival rates were similar between the two groups (86% and 77% versus 78% and 62%, respectively; p = 0.34). The independent predictor of survival in PVT patients with decompensated cirrhosis was the degree of MPV occlusion (hazard ratio 0.189, 95% CI 0.042-0.848).

CONCLUSIONS

TIPS should be considered a safe and feasible alternative therapy for chronic PVT in selected patients with decompensated cirrhosis. Both technical success and survival were closely associated with the degree of MPV occlusion.

Emerging issues in the use of transjugular intrahepatic portosystemic shunt (TIPS) for management of portal hypertension: time to update the guidelines?

Since its first introduction in the 1980s, transjugular intrahepatic portosystemic shunt has played an increasingly important role in the management and treatment of the complications of portal hypertension. In 2005, the American Association for the Study of Liver Diseases published the Practice Guidelines for the use of transjugular intrahepatic portosystemic shunt in the management of portal hypertension. Since then, technical advances and new interesting data on transjugular intrahepatic portosystemic shunt have been presented in the literature. The present review focus on the applications of transjugular intrahepatic portosystemic shunt and examines more recent studies on this topic; the current guidelines on the use of transjugular intrahepatic portosystemic shunt are also discussed. From the data presented in the most recent publications, it has become increasingly clear that the recommendations stemming from the current guidelines need to be reviewed and updated in several points. Changes in the American Association for the Study of Liver Diseases Practice Guidelines are needed for both common indications (variceal bleeding and refractory ascites) as well as uncommon ones (i.e., Budd-Chiari syndrome and portal cavernoma). In addition, a relevant technical advance has been the introduction of the polytetrafluoroethylene-covered stents, which greatly improved the patency and clinical efficacy of transjugular intrahepatic portosystemic shunt. Consequently, new studies are required to re-assess the role of transjugular intrahepatic portosystemic shunt performed with new covered stents as compared with other strategies in the management of portal hypertension.

Portal vein thrombosis, revisited

This review article aims to discuss the aetiology, pathophysiology, clinical presentation, diagnostic workup and management of portal vein thrombosis, either as a primary vascular liver disease in adults and children, or as a complication of liver cirrhosis. In addition, indications and limits of anticoagulant therapy are discussed in detail.

Systematic review: portal vein thrombosis in cirrhosis

BACKGROUND

As current imaging techniques in cirrhosis allow detection of asymptomatic portal vein thrombosis during routine ultrasonography, more patients with cirrhosis are diagnosed with portal vein thrombosis. Although a consensus on noncirrhotic extra-hepatic portal vein thrombosis has been published, no such consensus exists for portal vein thrombosis with cirrhosis.

AIM

To perform a systematic review of nonmalignant portal vein thrombosis in cirrhosis in terms of prevalence, pathogenesis, diagnosis, clinical course and management.

METHODS

Studies were identified by a search strategy using MEDLINE and EMBASE.

RESULTS

Portal vein thrombosis is encountered in 10-25% of cirrhotics. In terms of pathophysiology, cirrhosis is no longer considered a hypocoagulable state; rather than a bleeding risk in cirrhosis, various clinical studies support a thrombotic potential. Clinical findings of portal vein thrombosis in cirrhosis vary from asymptomatic disease to a life-threatening condition at first presentation. Optimal management of portal vein thrombosis in cirrhosis is currently not addressed in any consensus publication. Treatment strategies most often include the use of anticoagulation, while thrombectomy and transjugular intrahepatic portosystemic shunts are considered second-line options.

CONCLUSIONS

Portal vein thrombosis in cirrhosis has many unresolved issues, which are often the critical problems clinicians encounter in their everyday practice. We propose a possible research agenda to address these unresolved issues.

Management of portal vein thrombosis in cirrhotic patients

Portal vein thrombosis (PVT) not associated with hepatocellular carcinoma is considered a frequent complication of liver cirrhosis but, unlike PVT occurring in non-cirrhotic patients, very few data are available on its natural history and management. The reduced portal blood flow velocity is the main determinant of PVT but, as in other venous thromboses, multiple factors local and systemic, inherited or acquired often can concur with. PVT has a variety of clinical presentations ranging from asymptomatic to life-threatening diseases like gastroesophageal bleeding or acute intestinal ischemia. It is usually diagnosed by Doppler ultrasound but computed tomography and magnetic resonance imaging are useful to study the extent of thrombosis and the involvement of the abdominal organs. The risk of bleeding mainly determined by the presence of gastroesophageal varices and clotting alterations causes concern for the treatment of PVT in cirrhotic patients. To date, anticoagulant therapy seems to be indicated only in patients awaiting liver transplantation. This review focuses on the definition of the subgroups of patients with cirrhosis that might benefit from treatment of PVT and examines the pros and cons of the available treatments in terms of efficacy, monitoring and safety, providing also perspectives for future studies.

Hypercoagulation and thrombophilia in liver disease

A complex balance exists between endogenous procoagulants and the anticoagulant system in liver disease patients. Hypercoagulable events occur in cirrhosis patients despite the well-known bleeding diathesis of liver disease. These events may be clinically evident, such as in portal vein thrombosis or pulmonary embolism, but these conditions may also be a silent contributor to certain disease states, such as portopulmonary hypertension or parenchymal extinction with liver atrophy as well as thrombosis of extracorporeal circuits in dialysis or liver assist devices. Moreover, liver disease-related hypercoagulability may contribute to vascular disease in the increasingly common condition of non-alcoholic fatty liver disease. Despite the incidence of these problems, there are few widely accessible and practical laboratory tests to evaluate the risk of a hypercoagulable event in cirrhosis patients. Furthermore, there is little research on the use of commonly accepted anticoagulants in patients with liver disease. This article is a result of an international symposium on coagulation disorders in liver disease and addresses several areas of specific interest in hypercoagulation in liver disease. Critical areas lacking clinical information are highlighted and future areas of research interest are defined with an aim to foster clinical research in this field.