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

Portal vein thrombosis: diagnosis, management, and endpoints for future clinical studies

Portal vein thrombosis (PVT) refers to the development of a non-malignant obstruction of the portal vein, its branches, its radicles, or a combination. This Review first provides a comprehensive overview of all aspects of PVT, namely the specifics of the portal venous system, the risk factors for PVT, the pathophysiology of portal hypertension in PVT, the interest in non-invasive tests, as well as therapeutic approaches including the effect of treating risk factors for PVT or cause of cirrhosis, anticoagulation, portal vein recanalisation by interventional radiology, and prevention and management of variceal bleeding in patients with PVT. Specific issues are also addressed including portal cholangiopathy, mesenteric ischaemia and intestinal necrosis, quality of life, fertility, contraception and pregnancy, and PVT in children. This Review will then present endpoints for future clinical studies in PVT, both in patients with and without cirrhosis, agreed by a large panel of experts through a Delphi consensus process. These endpoints include classification of portal vein thrombus extension, classification of PVT evolution, timing of assessment of PVT, and global endpoints for studies on PVT including clinical outcomes. These endpoints will help homogenise studies on PVT and thus facilitate reporting, comparison between studies, and validation of future studies and trials on PVT.

Comparison of specialized stent versus generic stent and bare stent combination for transjugular intrahepatic portosystemic shunt creation

Transjugular intrahepatic portosystemic shunt (TIPS) creation using the Viatorr stent remains relatively uncommon in underdeveloped and high-burden disease regions in Asia-Pacific, and there is a lack of comparative studies regarding its prognostic effects compared with the generic stent-graft/bare stent combination. The purpose of this retrospective study is to compare the prognostic endpoints of these two treatments in patients who underwent TIPS creation. Clinical data from 145 patients were collected, including 82 in the combination group and 63 in the Viatorr group. Differences in prognostic endpoints (shunt dysfunction, death, overt hepatic encephalopathy [OHE], rebleeding) between the two groups were analyzed using Kaplan-Meier curves. The Cox proportional hazards model was used to identify independent risk factors for post-TIPS shunt dysfunction. The TIPS procedure was successful in all patients. After TIPS creation, both groups showed a significant decrease in porto-caval pressure gradient compared to that before TIPS creation. The stent patency rates at 6, 12, and 18 months were high in both the combination and Viatorr groups (93.7%, 88.5%, and 88.5% vs. 96.7%, 93.4%, and 93.4%, respectively). The stent patency rates was higher in the combination group than in the Viatorr group, although not statistically significant (HR = 2.105, 95% CI 0.640-6.922, Log-rank P = 0.259). There were no significant differences in other prognostic endpoints (death, OHE, rebleeding) between the two groups. The Cox model identified portal vein diameter (HR = 0.807, 95% CI 0.658-0.990, P = 0.040) and portal vein thrombosis (HR = 13.617, 95% CI 1.475-125.678, P = 0.021) as independent risk factors for post-TIPS shunt dysfunction. The shunt patency rates between the Viatorr stent and the generic stent-graft/bare stent combination showed no significant difference and the generic stent-graft/bare stent combination may be a viable alternative in areas where the Viatorr stent is not yet available.

Safety and efficacy of transjugular intrahepatic portosystemic shunts vs endoscopic band ligation plus propranolol in patients with cirrhosis with portal vein thrombosis: a systematic review and meta-analysis

BACKGROUND

This systematic review and meta-analysis aimed to assess the efficacy and safety of transjugular intrahepatic portosystemic shunts (TIPS) against the combined treatment of endoscopic band ligation (EBL) and propranolol in managing patients with cirrhosis diagnosed with portal vein thrombosis (PVT).

METHODS

A literature search from inception to September 2023 was performed using MEDLINE, the Cochrane Library, Web of Science, and Scopus. Independent screening, data extraction, and quality assessment were performed. The main measured outcomes were the incidence and recurrence of variceal bleeding (VB), hepatic encephalopathy, and overall survival.

RESULTS

A total of 5 studies were included. For variceal eradication, there was initially no significant difference between the groups; however, after sensitivity analysis, a significant effect emerged (risk ratio [RR], 1.55; P < .0001). TIPS was associated with a significant decrease in the incidence of VB (RR, 0.34; P < .0001) and a higher probability of remaining free of VB in the first 2 years after the procedure (first year: RR, 1.41; P < .0001; second year: RR, 1.58; P < .0001). TIPS significantly reduced the incidence of death due to acute GI bleeding compared with EBL + propranolol (RR, 0.37; P = .05).

CONCLUSION

TIPS offers a comprehensive therapeutic advantage over the combined EBL and propranolol regimen, especially for patients with cirrhosis with PVT. Its efficacy in variceal eradication, reducing rebleeding, and mitigating death risks due to acute GI bleeding is evident.

Natural History and Outcomes of Cavernous Transformation of the Portal Vein in Cirrhosis

BACKGROUND AND AIMS

Cavernous transformation of the portal vein can occur after portal vein thrombosis (PVT). In this study, we investigated clinical complications associated with cavernous transformation in the context of cirrhosis and PVT.

METHODS

In this retrospective cohort analysis, 204 patients with cirrhosis and PVT with or without cavernous transformation were identified using MUSC's Clinical Data Warehouse between January 1, 2013, through December 31, 2019. Complete demographic data, clinical history, and laboratory tests were abstracted from the electronic medical record.

RESULTS

Of 204 patients, 41 (20%) had cavernous transformation. MELD, Child-Pugh, and Charlson Comorbidity Index scores were similar among groups. There were no significant differences in the prevalence of esophageal varices (with or without bleeding), splenomegaly, or hepatic encephalopathy in patients with and without cavernous transformation, although ascites tended to be lower in patients with cavernous transformation (31/41 (76%) vs 142/163 (87%), p = 0.06). Patients with cavernous transformation were significantly less likely to have hepatocellular carcinoma (HCC) (13/41 (32%) vs 81/163 (50%), p < 0.05) and had significantly lower APRI (1.4 vs 2.0, p < 0.05) and Fib-4 (4.7 vs 6.5, p < 0.05). Patients with cavernous transformation had lower 5-year mortality (12/41 (29%) vs 81/163 (49%) died, p = 0.06). The 10-year mortality of patients with cavernous transformation without HCC was significantly lower than in those without cavernous transformation (8/28 (29%) vs 46/82 (56%), respectively, p < 0.05).

CONCLUSIONS

Patients with cavernous transformation appeared to have better outcomes than those without cavernous transformation.

Interventional Approach to Portal Vein Thrombosis and Liver Transplantation: State of the Art

Porto-mesenteric vein thrombosis (PVT) is a well-recognized but uncommon disease entity in patients with and without cirrhosis. Given the complexity of these patients, there are many differing treatment algorithms depending on the individual circumstances of a given patient. The focus of this review is primarily patients with cirrhosis, with an emphasis on liver transplantation considerations. The presence of cirrhosis substantially affects work-up, prognosis, and management of these patients and will substantially affect the patient treatment and have additional implications for prognosis and long-term outcomes. Here, we review the incidence of portal vein thrombosis in known cirrhotic patients, medical and interventional treatment options that are currently used, and, in particular, how to approach cirrhotic patients with PVT who are awaiting liver transplantation.

Alternative forms of portal vein revascularization in liver transplant recipients with complex portal vein thrombosis

BACKGROUND & AIMS

Complex portal vein thrombosis (PVT) is a challenge in liver transplantation (LT). Extra-anatomical approaches to portal revascularization, including renoportal (RPA), left gastric vein (LGA), pericholedochal vein (PCA), and cavoportal (CPA) anastomoses, have been described in case reports and series. The RP4LT Collaborative was created to record cases of alternative portal revascularization performed for complex PVT.

METHODS

An international, observational web registry was launched in 2020. Cases of complex PVT undergoing first LT performed with RPA, LGA, PCA, or CPA were recorded and updated through 12/2021.

RESULTS

A total of 140 cases were available for analysis: 74 RPA, 18 LGA, 20 PCA, and 28 CPA. Transplants were primarily performed with whole livers (98%) in recipients with median (IQR) age 58 (49-63) years, model for end-stage liver disease score 17 (14-24), and cold ischemia 431 (360-505) minutes. Post-operatively, 49% of recipients developed acute kidney injury, 16% diuretic-responsive ascites, 9% refractory ascites (29% with CPA, p <0.001), and 10% variceal hemorrhage (25% with CPA, p = 0.002). After a median follow-up of 22 (4-67) months, patient and graft 1-/3-/5-year survival rates were 71/67/61% and 69/63/57%, respectively. On multivariate Cox proportional hazards analysis, the only factor significantly and independently associated with all-cause graft loss was non-physiological portal vein reconstruction in which all graft portal inflow arose from recipient systemic circulation (hazard ratio 6.639, 95% CI 2.159-20.422, p = 0.001).

CONCLUSIONS

Alternative forms of portal vein anastomosis achieving physiological portal inflow (i.e., at least some recipient splanchnic blood flow reaching transplant graft) offer acceptable post-transplant results in LT candidates with complex PVT. On the contrary, non-physiological portal vein anastomoses fail to resolve portal hypertension and should not be performed.

IMPACT AND IMPLICATIONS

Complex portal vein thrombosis (PVT) is a challenge in liver transplantation. Results of this international, multicenter analysis may be used to guide clinical decisions in transplant candidates with complex PVT. Extra-anatomical portal vein anastomoses that allow for at least some recipient splanchnic blood flow to the transplant allograft offer acceptable results. On the other hand, anastomoses that deliver only systemic blood flow to the allograft fail to resolve portal hypertension and should not be performed.

Portal Vein Thrombosis in the Setting of Cirrhosis: A Comprehensive Review

Portal vein thrombosis constitutes the most common thrombotic event in patients with cirrhosis, with increased rates in the setting of advanced liver disease. Despite being a well-known complication of cirrhosis, the contribution of portal vein thrombosis to hepatic decompensation and overall mortality is still a matter of debate. The incorporation of direct oral anticoagulants and new radiological techniques for portal vein recanalization have expanded our therapeutic arsenal. However, the lack of large prospective observational studies and randomized trials explain the heterogenous diagnostic and therapeutic recommendations of current guidelines. This article seeks to make a comprehensive review of the pathophysiology, clinical features, diagnosis, and treatment of portal vein thrombosis in patients with cirrhosis.

Absence of large portal collateral vessels is associated with spontaneous improvement of cirrhotic portal vein thrombosis

AIM

Portal vein thrombosis (PVT) is a major complication in patients with liver cirrhosis (LC). In some cases, PVT decreases spontaneously, but the factors that predict this are still not fully understood.

METHODS

This was a retrospective, multicenter study that included 77 consecutive patients with cirrhotic PVT. Forty-eight patients did not undergo anticoagulation and 29 patients did between the time of the first diagnosis of PVT and the follow-up radiological imaging undertaken 1-6 months later. A complete disappearance and 25% shrinkage of PVT was defined as complete remission (CR) and partial remission (PR), respectively. Portosystemic collateral vessels larger than 9 mm in diameter were defined as large collateral vessels.

RESULTS

Complete remission + PR was found in 37.5% of the anticoagulation-naïve patients. On univariate analysis, the absence of large collateral vessels, absence of PVT in the main trunk of the portal vein, a high platelet count, and a low FIB-4 index were significant factors associated with CR + PR. On multivariate analysis, the absence of large collateral vessels was the unique factor associated with CR + PR of PVT (odds ratio 5.9; 95% confidence interval, 1.73-20.1). The CR + PR rate for anticoagulated patients was 44.8%. However, no predictors for a good treatment effect of anticoagulation for PVT were identified.

CONCLUSIONS

Spontaneous improvement of PVT in patients with LC can be expected when large collateral vessels are absent. For these patients, the option of observing them without anticoagulation can be considered in expectation of spontaneous reduction of PVT.

Meta-analysis and systematic review: Prevalence, graft failure, mortality, and post-operative thrombosis in liver transplant recipients with pre-operative portal vein thrombosis

AIMS

This study seeks to evaluate the association between pre-transplant portal vein thrombosis (PVT) and overall survival, graft failure, waitlist mortality, and post-operative PVT after liver transplantation.

METHODS

A conventional pairwise meta-analysis between patients with and without pre-transplant PVT was conducted using hazard ratios or odds ratios where appropriate.

RESULTS

Prevalence of preoperative PVT was 11.6% (CI 9.70-13.7%). Pre-operative PVT was associated with increased overall mortality (HR 1.45, 95% CI 1.27-1.65) and graft loss (HR 1.58, 95% CI 1.34-1.85). In particular, grade 3 (HR 1.59, 95% CI 1.00-2.51) and 4 (HR 2.24, 95% CI 1.45-3.45) PVT significantly increased mortality, but not grade 1 or 2 PVT. Patients with PVT receiving living donor (HR 1.54, 95% CI 1.24-1.91) and deceased donor (HR 1.52, 95% CI 1.21-1.92) liver transplantation had increased mortality, with no significant difference between transplant types (P = .13). Furthermore, pre-transplant PVT was associated with higher occurrence of post-transplant PVT (OR 5.06, 95% CI 3.89-6.57). Waitlist mortality was not significantly increased in patients with pre-transplant PVT.

CONCLUSION

Graft failure, mortality, and post-operative PVT are more common in pre-transplant PVT patients, especially in grade 3 or 4 PVT. Prophylactic anticoagulation can be considered to reduce re-thrombosis and improve survival.

Liver transplantation in patients with non-neoplastic portal vein thrombosis: 20 years of experience in a single center

BACKGROUND

The Yerdel classification is widely used for describing the severity of portal vein thrombosis (PVT) in liver transplant (LT) candidates, but might not accurately predict transplant outcome.

METHODS

We retrospectively analyzed data regarding 97 adult patients with PVT who underwent LT, investigating whether the complexity of portal reconstruction could better correlate with transplant outcome than the site and extent of the thrombosis.

RESULTS

79/97 (80%) patients underwent thrombectomy and anatomical anastomosis (TAA), 18/97 (20%) patients underwent non-anatomical physiological reconstructions (non-TAA). PVT Yerdel grade was 1-2 in 72/97 (74%) patients, and 3-4 in 25/97 (26%) patients. Univariate analysis revealed higher 30-day mortality, 90-day mortality, 1-year mortality, and a higher rate of severe early complications in the non-TAA group than in the TAA group (p = .018, .001, .014, .009, respectively). In the model adjusted for PVT Yerdel grade, non-TAA remained independently associated with higher 30-day, 90-day, and 1-year mortality (p = .021, .007, and .015, respectively). The portal vein re-thrombosis and overall patient and graft survival rates were similar.

DISCUSSION

In our experience, the complexity of portal reconstruction better correlated with transplant outcome than the Yerdel classification, which did not even appear to be a reliable predictor of the surgical complexity and technique.

Evolution of Nonmalignant Portal Vein Thrombosis in Liver Cirrhosis: A Pictorial Review

Portal vein thrombosis (PVT) is a common complication in liver cirrhosis, especially in advanced cirrhosis. It may be related to a higher risk of liver-related events and liver function deterioration. Imaging examinations can not only provide an accurate diagnosis of PVT, such as the extent of thrombus involvement and the degree of lumen occupied, but also identify the nature of thrombus (i.e., benign/malignant and acute/chronic). Evolution of PVT, mainly including development, recanalization, progression, stability, and recurrence, could also be assessed based on the imaging examinations. This article briefly reviews the pathophysiology, diagnosis, classification, and evolution of PVT with an emphasis on their computed tomography imaging features.

Transjugular intrahepatic portosystemic shunts in portal vein thrombosis: A review

The presence of portal vein thrombosis (PVT) has previously been considered a contraindication to the insertion of transjugular intrahepatic portosystemic shunts (TIPSS). However, patients with PVT may have portal hypertension complications and may thus benefit from TIPSS to reduce portal venous pressure. There is an increasing body of literature that discusses the techniques and outcomes of TIPSS in PVT. This review summarizes the techniques, indications and outcomes of TIPSS in PVT in published case reports, case series and comparative trials, especially regarding the reduction in portal hypertensive complications such as variceal bleeding. A comprehensive literature search was conducted using MEDLINE and PubMed databases. Manuscripts published in English between 1 January 1990 and 1 March 2021 were used. Abstracts were screened and data from potentially relevant articles analyzed. TIPSS in PVT has been reported with high levels of technical success, short-term portal vein recanalization and long-term PV patency and TIPSS patency outcomes. Several comparative studies, including randomized controlled trials, have shown favorable outcomes of TIPSS compared with non-TIPSS treatment of PVT complications. Outcomes of TIPSS with PVT appear similar to those in TIPSS without PVT. However, TIPSS may be more technically difficult in the presence of PVT, and such procedures should be performed in expert high-volume centers to mitigate the risk of procedural complications. The presence of PVT should no longer be considered a contraindication to TIPSS. TIPSS for PVT has been acknowledged as a therapeutic strategy in recent international guidelines, although further studies are needed before recommendations can be strengthened. KEY POINTS: Portal vein thrombosis (PVT) is no longer a contraindication to the insertion of transjugular intrahepatic portosystemic shunts (TIPSS) TIPSS often leads to the spontaneous dissolution of PVT, but can be combined with mechanical or pharmacological thrombectomy TIPSS reduces portal hypertensive complications of PVT, such as variceal bleeding, and can also facilitate liver transplantation where PVT may otherwise interfere with vascular anastomoses Studies have shown favorable long-term outcomes of TIPSS compared with TIPSS without PVT; as well as compared with non-TIPSS treatment of PVT complications TIPSS in PVT should be performed in high-volume specialist centers due to technical difficulties.

Current knowledge and management of portal vein thrombosis in cirrhosis

Portal vein thrombosis (PVT) is an increasingly recognised complication of cirrhosis whose incidence increases in parallel with the severity of cirrhosis. Several risk factors have been associated with the occurrence and progression of PVT. Although the negative effect of complete PVT on the surgical outcome of liver transplant recipients is clear, its impact on cirrhosis progression remains uncertain. Treatment options include anticoagulants and interventional thrombolytic therapies, which are chosen almost on a case-by-case basis depending on the characteristics of the patient and the thrombus. In this manuscript, we review current knowledge regarding the epidemiology, risk factors, diagnosis and classification, natural history, clinical consequences and treatment of non-neoplastic PVT in cirrhosis.

Nontumoral Portal Vein Thrombosis: A Challenging Consequence of Liver Cirrhosis

Nontumoral portal vein thrombosis (PVT) is an increasingly recognized complication in patients with cirrhosis. Substantial evidence shows that portal flow stasis, complex thrombophilic disorders, and exogenous factors leading to endothelial dysfunction have emerged as key factors in the pathogenesis of PVT. The contribution of PVT to hepatic decompensation and mortality in cirrhosis is debatable; however, the presence of an advanced PVT increases operative complexity and decreases survival after transplantation. The therapeutic decision for PVT is often determined by the duration and extent of thrombosis, the presence of symptoms, and liver transplant eligibility. Evidence from several cohorts has demonstrated that anticoagulation treatment with vitamin K antagonist or low molecular weight heparin can achieve recanalization of the portal vein, which is associated with a reduction in portal hypertension-related events and improved survival in cirrhotic patients with PVT. Consequently, interest in direct oral anticoagulants for PVT is increasing, but clinical data in cirrhosis are limited. Although the most feared consequence of anticoagulation is bleeding, most studies indicate that anticoagulation therapy for PVT in cirrhosis appears relatively safe. Interestingly, the data showed that transjugular intrahepatic portosystemic shunt represents an effective adjunctive therapy for PVT in cirrhotic patients with symptomatic portal hypertension if anticoagulation is ineffective. Insufficient evidence regarding the optimal timing, modality, and duration of therapy makes nontumoral PVT a challenging consequence of cirrhosis. In this review, we summarize the current literature and provide a potential algorithm for the management of PVT in patients with cirrhosis.

Placement of a transjugular intrahepatic portosystemic shunt in addition to recanalization of acute and chronic portomesenteric vein occlusions - a retrospective evaluation

Background

Portomesenteric vein thrombosis may be life-threatening due to bowel ischemia caused by venous stasis, or variceal bleeding caused by portal hypertension.

Purpose

To evaluate the effectiveness and safety of recanalization combined with transjugular intrahepatic portosystemic shunt in acute and chronic portomesenteric vein thrombosis in patients with and without liver cirrhosis.

Material and Methods

21 consecutive patients (5 women, 16 men; mean 48 years) with portomesenteric vein thrombosis (8 acute, 13 chronic) treated at the Interventional Radiology department between March 2014 and September 2018 were retrospectively reviewed. The main portal vein was completely obliterated and the portomesenteric vein thrombosis extended into the superior mesenteric vein in all patients. The portomesenteric vein thromboses were recanalized transhepatically, a transjugular intrahepatic portosystemic shunt was inserted, thrombectomy was performed in acute portomesenteric vein thrombosis, and angioplasty with or without additional stenting was performed in chronic portomesenteric vein thrombosis.

Results

Recanalization was successful in 8/8 patients (100%) with acute portomesenteric vein thrombosis, and in 11/13 patients (85%) with chronic portomesenteric vein thrombosis. In 12 patients, blood flow was restored in one session. Several sessions were more frequently needed in patients with acute portomesenteric vein thrombosis compared to those with chronic portomesenteric vein thrombosis (p = 0.003). Re-occlusion occurred and was recanalized in 10/19 patients and was more frequent in patients with chronic (n = 8/11) than on those with acute (n = 2/8) portomesenteric vein thrombosis (p = 0.04). Adverse events occurred in five patients. There was no 30-day mortality.

Conclusion

Recanalization and insertion of a transjugular intrahepatic portosystemic shunt is safe and effective in patients with acute and chronic portomesenteric vein thrombosis with or without cirrhosis. Recanalization was more likely to stay patent in acute compared with chronic portomesenteric vein thrombosis.

Multivisceral transplant as an option to transplant cirrhotic patients with severe portal vein thrombosis

Non-tumoral portal vein thrombosis (PVT) is a critical complication in the patient with advanced cirrhosis awaiting liver transplantation (LT). With the evolution of liver transplant (LT) technique, PVT has morphed from an absolute contraindication to a relative contraindication, depending on the grade of the thrombus. The Yerdel classification is one system of grading PVT severity. Patients with Yerdel class 1-3 PVT can undergo LT at centers with experience in complex portal vein (PV) dissection, thrombectomy, and reconstruction. Class 4 PVT, however, is even more complex and may require heroic techniques such as cavoportal hemitransposition, PV arterialization or multivisceral transplant (MVT). Some centers use a MVT back-up approach for patients with Yerdel class 4 PVT. In these patients, all organs with PV outflow are procured simultaneously as a cluster graft from a deceased donor (liver, pancreas, intestine±stomach). If physiologic PV inflow is established intraoperatively, the recipient undergoes LT. Otherwise the MVT graft is transplanted. MVT establishes physiologic PV flow, but transplantation of the intestine confers significant lifelong risks including rejection, graft-versus host disease and post-transplant lymphoma. Yerdel class 1-4 PVT patients undergoing successful LT have 5-year survival similar to non-PVT patients, while patients requiring full MVT experience somewhat higher mortality because of the complexity of the surgery and medical management.

A prospective, multicentre study in acute non-cirrhotic, non-malignant portal vein thrombosis: comparison of medical and interventional treatment

BACKGROUND

To evaluate medical versus interventional treatment (transjugular thrombus fragmentation, local thrombolysis with or without stent implantation) in patients with acute non-cirrhotic, non-malignant portal vein thrombosis (PVT).

METHODS

This prospective, observational study enrolled 65 patients with acute (<28 days since begin of symptoms, no cavernoma) PVT in nine centres. Thirty patients received medical treatment and 35 patients received interventional treatment. PVT was graded into grade 1: short thrombosis and incomplete occlusion of the vessel lumen and grade 2: extended thrombosis or complete occlusion. Treatment response was classified as partial or complete, if thrombosis was reduced by one grade or to <25% of the vessel diameter respectively.

RESULTS

Partial and complete response rates were 7% and 30% in the medical compared to 17% and 54% (P < 0.001) in the interventional treatment group. In the multivariate analysis, interventional treatment showed a strong positive (OR 4.32, P < 0.016) and a myeloproliferative aetiology a negative (OR 0.09, P = 0.006) prediction of complete response. Complications were rare in the medical group and consisted of septicaemia and upper gastrointestinal bleeding of unknown origin in one patient each. Interventional treatment was accompanied by mild and self-limiting bleeding complications in nine patients, moderate intra-abdominal bleeding requiring transfusions (2 units) in one patient and peritoneal bleeding requiring surgical rescue in one patient. Four patients in each group developed intestinal gangrene requiring surgery. One patient died 52 days after unsuccessful interventional treatment.

CONCLUSIONS

Compared to medical treatment alone, interventional treatment doubled response rates at the cost of increased bleeding complications.

Current management of portal vein thrombosis in liver transplantation

Nontumoral portal vein thrombosis (PVT) is present at liver transplantation (LT) in 5-26% of cirrhotic patients, and is known to affect post LT outcomes. Up to 31% of patients who are found to have PVT at the time of LT, would have had PVT at the time of initial listing, but others develop PVT during the waiting period. Adequate screening and treatment of the PVT on the waiting list for LT is thus essential so that a portoportal anastomoses can be performed at the time of LT. Early PVT (Yerdel Grade I/II) can be usually managed by thrombectomy, whereas Grade III PVT may require a jump graft from the superior mesenteric vein to the graft PV. Complete portomesenteric thrombosis is a huge challenge, and sometimes a cause for denying a LT in these patients, with multivisceral transplant being the only alternative. The presence of spontaneous, or previously surgically created portosytemic shunts like the leinorenal shunt, may serve as a good inflow option (renoportal anastomosis) in these patients to establish a physiological reconstruction. Although challenging, good outcomes are possible in patients with complex PVT if the appropriate surgical technique is chosen to ensure portal inflow and resolution of PHT post LT.

Danaparoid sodium-based anticoagulation therapy for portal vein thrombosis in cirrhosis patients

Background

Portal vein thrombosis (PVT) is a common complication of cirrhosis. However, in patients with PVT and cirrhosis, there is no clear evidence supporting effective treatment modalities. In this study, we examined the effectiveness and safety of anticoagulation therapy using danaparoid sodium for PVT in patients with cirrhosis.

Methods

This retrospective study assessed 52 cirrhotic patients with PVT treated with danaparoid sodium for 2 weeks between November 2008 and September 2018. The primary outcome measure was the post-treatment status of PVT assessed by reduction in thrombus volume and safety of the therapeutic intervention. PVT status was evaluated with contrast-enhanced computed tomography (CECT). All patients received 1250 units of danaparoid sodium twice daily by intravenous injection for 14 days. Patients on antithrombin III (AT-III) combination therapy were additionally administered 1500 units of AT-III on days 1–5 and days 8–12. Effectiveness was evaluated by CECT from between days 13 and 18. The secondary outcome measure was the prognosis of PVT.

Results

All patients showed reduction in PVT volume without complications. Return of plasma AT-III level to > 70% during the treatment period contributes to ≥75% reduction of PVT volume. The prognosis in PVT patients depends on hepatic reserve capacity. When limited to Child-Pugh B and C liver cirrhosis patients, a ≥ 75% reduction of PVT volume improved the prognosis.

Conclusions

Danaparoid sodium-based anticoagulation therapy was effective and safe for PVT in patients with cirrhosis. Return of plasma AT-III level to the normal range during the treatment period contributes to reduction of PVT volume. A reduction of ≥75% in PVT volume may improve the prognosis of Child-Pugh B and C decompensated cirrhosis patients with PVT.

Novel classification of non-malignant portal vein thrombosis: A guide to surgical decision-making during liver transplantation

Non-tumoral portal vein thrombosis (PVT) is present at liver transplantation in 5% to 26% of cirrhotic patients, and the prevalence of complex PVT as defined here (grade 4 Yerdel, and grade 3,4 Jamieson and Charco) has been reported in 0% to 2.2%. Adequate portal inflow is mandatory to ensure graft and patient survival after liver transplantation. With time, the proposed classifications of non-tumoral chronic PVT have evolved from being anatomy-based, to also incorporating functional parameters. However, none of the currently proposed classifications are directed towards decision-making, regarding the choice of inflow to the graft during transplantation and the outcomes thereof. The present scoping review i) addresses the limits of the currently available classifications in terms of surgical decisiveness, ii) clarifies the concept of physiological or non-physiological portal inflow reconstruction, and subsequently, iii) proposes a new classification of non-tumoral PVT in candidates for liver transplantation; to help tailor the surgical strategy to an individual patient, in order to provide portal inflow to the graft together with control of prehepatic portal hypertension whenever feasible.

High-density lipoprotein cholesterol for the prediction of mortality in cirrhosis with portal vein thrombosis: a retrospective study

BACKGROUND

Lipid profiles disorders frequently occur in patients with chronic liver diseases, and the mortality of cirrhosis complicated with portal vein thrombosis (PVT) remains high. Research identifying simple and objective prognosis indicators for cirrhotic PVT has been limited. The aim of the present study was to investigate the association between lipid profiles and liver function, which may help predict the 1-year mortality in non-malignant cirrhosis with PVT.

METHODS

A retrospective cohort of 117 subjects with non-malignant cirrhotic PVT was conducted. The primary indicators of lipid profiles included triglyceride, cholesterol, high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol. Correlations of lipid profiles with liver function tests, the Child-Turcotte-Pugh (CTP) score and the model for end-stage liver disease (MELD) score were investigated. The relationship between lipid profiles and 1-year mortality was assessed using the area under the receiver operating characteristic curves (AUROC). Logistic regression models were established to confirm the association between HDL-C and mortality.

RESULTS

The level of HDL-C was significantly decreased in non-survivors (p < 0.01) and patients with more severe liver damage stages (CTP p < 0.001; MELD p < 0.001). There was no significant difference in the HDL-C level among patients with different severities of PVT (p = 0.498). The level of HDL-C was positively correlated with albumin (p < 0.001, R = 0.438) and platelet (p = 0.022, R = 0.212) levels. The level of HDL-C was negatively correlated with bilirubin (p < 0.001, R = - 0.319), C-reactive protein (p < 0.001, R = - 0.342), the aspartate aminotransferase to alanine aminotransferase ratio (p < 0.0.1, R = - 0.237), the CTP score (p < 0.001, R = - 0.397) and the MELD score (p < 0.001, R = - 0.406). The 1-year mortality rate was 12.8%. The AUROC of HDL-C for the prediction of 1-year mortality in this population was 0.744 (p < 0.01, 95%CI 0.609-0.879). The level of HDL-C was independently associated with mortality by multivariate logistic regression models.

CONCLUSIONS

The HDL-C level significantly decreases with the deterioration of liver function, which may serve as a potential indicator for the prognosis of non-malignant cirrhotic patients with PVT.

Systematic review with meta-analysis: portal vein recanalisation and transjugular intrahepatic portosystemic shunt for portal vein thrombosis

BACKGROUND

Transjugular intrahepatic portosystemic shunt has been increasingly used in patients with portal vein thrombosis to obtain patency, but evidenced-based decisions are challenging.

AIM

To evaluate published data on efficacy and safety of endovascular therapy in portal vein thrombosis.

METHODS

Systematic search of PubMed, ISI, Scopus, and Embase for studies (in English, until October 2017) reporting feasibility, safety, 12-month portal vein recanalisation, transjugular intrahepatic portosystemic shunt patency, and survival in patients with benign portal vein thrombosis undergoing endovascular treatment. An independent extraction of articles using predefined data fields and quality indicators was used; pooled analyses based on random-effects models; heterogeneity assessment by Cochran's Q, I² statistic, subgroup analyses, and meta-regression.

RESULTS

Thirteen studies including 399 patients (92% cirrhosis; portal vein thrombosis: complete 46%, chronic 87%, cavernous transformation 17%, superior mesenteric vein involvement 55%) were included. Transjugular intrahepatic portosystemic shunt was technically feasible in 95% (95% CI: 89%-98%) with heterogeneity (I²  = 57%, P < 0.001) explained by cavernous transformation. Major complications occurred in 10% (95% CI: 6.0%-18.0%; I²  = 52%, P = 0.55). Additional catheter-directed thrombolysis was associated with more complications compared to transjugular intrahepatic portosystemic shunt alone or plus thrombectomy (17.6% vs 3.3%). Twelve-month portal vein recanalisation was 79% (95% CI: 67%-88%; I²  = 78%, P < 0.01). Shunt patency at 12 months was 84% (95% CI: 76%-90%; I²  = 62%, P < 0.01). Overall 12-month survival rate was 89%, with no heterogeneity.

CONCLUSIONS

Transjugular intrahepatic portosystemic shunt for portal vein thrombosis recanalisation was highly feasible, effective, and safe. Cavernous transformation was the main determinant of technical failure. Additional catheter-directed thrombolysis was associated with higher risk of severe complications.

The role of transjugular intrahepatic portosystemic shunt in the management of portal vein thrombosis: a systematic review and meta-analysis

BACKGROUND

The role of transjugular intrahepatic portosystemic shunt (TIPS) in the management of portal vein thrombosis (PVT) remains controversial. This study aimed to conduct a systematic review and meta-analysis to evaluate the role of TIPS for the management of PVT in adult patients with liver disease.

PATIENTS AND METHODS

Multiple databases were searched through April 2017. Data were gathered to estimate the rates of technical success, portal vein recanalization, portal patency, hepatic encephalopathy, and mean change in portal pressure gradient in patients with PVT who underwent TIPS. Estimates were pooled across studies using the random effects model.

RESULTS

Eighteen studies were included in the analysis. The pooled technical success rate was 86.7% [95% confidence interval (CI)=78.6-92.1%]. Rate of portal vein recanalization was 84.4% (95% CI=78.4-89.0%). The rate of complete recanalization was 73.7% (95% CI=64.3-81.3%). Portal patency was 86.9% (95% CI=79.7-91.8%). Mean change in portal pressure gradient was 14.5 mmHg (95% CI=11.3-17.7 mmHg). Hepatic encephalopathy was 25.3% (95% CI=19.2-32.6%). The number of major adverse events reported across studies was low. The majority of the analyses were not associated with substantial heterogeneity.

CONCLUSION

The use of TIPS in the management of PVT is feasible and effective in achieving a significant and sustainable reduction in clot burden with a low risk of major complications. TIPS should be considered as a viable treatment option in patients with PVT. Given the limited amount of randomized comparative studies reported, additional trials are warranted to assess the safety and efficacy of TIPS as a treatment modality in PVT, in comparison to other treatment options, such as anticoagulation.

New Techniques and Devices in Transjugular Intrahepatic Portosystemic Shunt Placement

Recently, new techniques and devices in transjugular intrahepatic portosystemic shunt (TIPS) placement have emerged that can improve upon the standard procedure. Ultrasound guidance during TIPS with intracardiac echocardiography (ICE), placement of controlled expansion (CX) stents, and portal vein recanalization (PVR) via transsplenic access are three techniques with new data supporting their implementation. ICE guidance can improve the technical success of difficult cases, decrease procedure time, and decrease complications such as capsular puncture, hemobilia, and hepatic artery injury. CX stents offer the operator better control over the final portosystemic gradient, which is particularly useful in patients with a high risk of post-TIPS hepatic encephalopathy. Finally, transsplenic access provides a stable, antegrade route for PVR, which can be used to optimize transplant candidacy as well as treat the sequelae of portal hypertension in patients with portal vein thrombosis. This article will describe the benefits, technical parameters, and patient selection criteria for each of these new techniques.

Portal Vein Thrombosis in Patients With Cirrhosis Undergoing Elective Transjugular Intrahepatic Portosystemic Shunt: Risk Factors, Warfarin Efficacy, and Clinical Outcomes

Portal vein thrombosis (PVT) is a common complication in cirrhosis. The aim of this study was to determine risk factors for PVT, assess the efficacy of anticoagulant therapy, and evaluate the effects of PVT on patients with cirrhosis undergoing elective transjugular intrahepatic portosystemic shunt (TIPSS). A total of 101 patients with cirrhosis undergoing elective TIPSS were prospectively studied. After TIPSS, all patients received preventive therapy for PVT and were followed up at 3, 6, 12, and 24 months. Clinical outcomes were compared between patients who developed PVT after TIPSS and those who did not. Multivariate analysis showed that white blood cell count (relative risk [RR]: 0.377; 95% confidence interval [CI]: 0.132-0.579; P = .001), Child-Turcotte-Pugh score (RR: 1.547; 95% CI: 1.029-2.365; P = .032), and ascites (RR: 1.264; 95% CI: 1.019-1.742; P = .040) were independent predictors for PVT. Warfarin treatment within 12 months achieved significantly higher rates of complete recanalization than aspirin or clopidogrel in patients with PVT (54.5% vs 31.3%; P = .013), although adverse events were similar between the 2 groups ( P > .05). Patients without PVT had significantly lower 2-year cumulative rates of variceal rebleeding (15.9% vs 36.6%; P = .023), shunt dysfunction (27.0% vs 46.8%; P = .039), hepatic encephalopathy (24.1% vs 42.6%; P = .045), and hepatocellular carcinoma (11.4% vs 31.2%; P = .024) and markedly higher 2-year cumulative survival rates (89.8% vs 72.9%; P = .041) than those with PVT. The PVT is associated with poorer clinical outcomes in TIPSS-treated patients, and warfarin is both safe and more effective in recanalizing PVT than aspirin or clopidogrel.

Analysis of the MELD Score Impact in the Outcome of Endovascular Portal Vein Reconstruction

INTRODUCTION

Endovascular therapy represents a less invasive alternative to open surgery for reconstruction of the portal vein (PV) and the spleno-mesenteric venous confluence to treat Portal hypertension. The objective of this study is to determine if the Model for End-Stage Liver Disease (MELD) score is a useful method to evaluate the risk of morbidity and mortality during endovascular approaches.

MATERIAL AND METHODS

Patients that underwent endovascular reconstruction of the PV or spleno-mesenteric confluence were identified retrospectively. Data were collected from November 2011 to August 2016. The MELD score was calculated using international normalized ratio, serum billirubin and creatinine. Patients were grouped into moderate (≤ 15) and high (> 15) MELD. Associations of the MELD score on the postprocedural morbidity, mortality and vessels patency were assessed by two-sided Fisher's exact test.

RESULTS

Seventeen patients were identified; MELD score distribution was: ≤ 15 in 10 patients (59%) and > 15 in 7 (41%). Even distribution of severe PV thrombosis was treated in both groups, performing predominately jugular access in the high MELD score group (OR 0.10; 95%; CI 0.014-0.89; p = 0.052) in contrast to a percutaneous transhepatic access in the moderate MELD score group. Analysis comparing moderate and high MELD scores was not able to demonstrate differences in mortality, morbidity or patency rates.

CONCLUSION

MELD score did not prove to be a useful method to evaluate risk of morbidity and mortality; however a high score should not contraindicate endovascular approaches. In our experience a high technical success, good patency rates and low complication rates were observed.

Outcomes of transjugular intrahepatic portosystemic shunt creation for flow-enabled dissolution of spleno-mesenterico-portal venous thrombosis

PURPOSE

To evaluate the outcomes of transjugular intrahepatic portosystemic shunt (TIPS) for flow-enabled clearance of portal (PVT), splenic (SVT) and/or superior mesenteric (MVT) vein thrombosis.

PATIENTS AND METHODS

In this single-center study, 12 patients underwent TIPS using Viatorr covered stent-grafts (W.L. Gore & Associates, Flagstaff, AZ, USA) from 2008-2014 for PVT as a primary (n=8) or secondary (n=4) indication. TIPS were not accompanied by pharmacomechanical clot disruption; rather, shunts served to increase portal blood flow to allow flow-mediated physiologic clot dissolution. Pre- and post-TIPS cross-sectional imaging were used to assess clot location, size, and clearance, defined by resolution (vessel patency with no clot), reduction (decrease in clot size), stability (no change in clot size), or extension (increase in clot size).

RESULTS

The cohort included 5 men and 7 women (median age 63 years, range 45-73 years, median MELD score 15) with 30 non-occlusive and asymptomatic thrombi spanning main or intrahepatic PVT (n=15/30, 50%), SVT (n=6/30, 20%), and MVT (n=9/30, 30%). TIPS were generally created with 10mm covered stent-grafts; mean final portosystemic pressure gradient was 8mmHg. At mean 190 days post-TIPS, 58% (n=7/12) had clot resolution, 33% (n=4/12) had clot reduction, and 8% (n=1/12) had stable clot; there were no cases of clot extension. Resolution rate was 67% for PVT (10/15), SVT (4/6), and MVT (6/9). Two of 12 (17%) patients underwent successful liver transplant post-TIPS.

CONCLUSION

TIPS prompts dissolution of or decrease in PVT, SVT, and MVT in cirrhotic patients. This may be a useful approach notwithstanding omission of pharmacomechanical methods.

Transjugular intrahepatic portosystemic shunt for portal vein thrombosis with variceal bleeding in liver cirrhosis: outcomes and predictors in a prospective cohort study

BACKGROUND & AIMS

The role of transjugular intrahepatic portosystemic shunt (TIPS) for the secondary prophylaxis of variceal bleeding in cirrhotic patients with portal vein thrombosis (PVT) remains obscure. This prospective cohort study aimed to assess the risk factors associated with TIPS technical success, outcome and prognosis in cirrhotic patients with PVT and a history of variceal bleeding.

METHODS

Between May 2009 and April 2011, 51 cirrhotic patients with PVT who attempted TIPS procedures for the prevention of variceal rebleeding were enrolled.

RESULTS

TIPS success rate was 84% (43/51). An increased degree of thrombosis within the portal trunk and portal vein branches was inversely associated with TIPS success. Median follow-up time was 40.07 months (range: 0.02-56.87). The cumulative risk of rebleeding was significantly different between TIPS success and failure group (P = 0.002). The univariate analysis also demonstrated that TIPS failure was the only significant predictor associated with rebleeding (hazard ratio [HR] = 4.174, 95% confidence interval [CI]: 1.558-11.186). In TIPS success group, the cumulative rates free of shunt dysfunction at the 6th and 12th month were 79% and 76% respectively. Absence of total superior mesenteric vein (SMV) thrombosis was the only independent predictor (HR = 0.189, 95% CI: 0.047-0.755). In TIPS success group, the 1- and 3-year cumulative survival rates were 77% and 62% respectively. Albumin level was the only independent predictor (HR = 0.877, 95% CI: 0.779-0.986).

CONCLUSION

Successful TIPS insertions could effectively prevent from rebleeding in cirrhotic patients with PVT and variceal bleeding. Degree of PVT and SMV thrombosis was associated with TIPS failure and shunt dysfunction respectively.

Clinical outcome comparison between TIPS and EBL in patients with cirrhosis and portal vein thrombosis

The aim of this study is to compare the clinical outcomes of transjugular intrahepatic portosystemic shunt (TIPS) and endoscopic band ligation (EBL) in patients with cirrhosis and portal vein thrombosis (PVT). We retrospectively reviewed the January to September 2010 data from our database and included 25 patients with cirrhosis and PVT who underwent successful TIPS creation. We selected another 25 patients who underwent EBL matching for age, sex, and Child-Pugh-Turcotte class. The outcome measures included changes in the PVT status before and after the treatments, the rebleeding rate, and the overall survival. The mean follow-up was 25.1 ± 8.7 months in the EBL group and 25.6 ± 8.5 months in the TIPS group (P = 0.85). After treatments, the PVT severity improved in 40% and worsened in 25% of patients who did not undergo TIPS, compared with 87% and none of the patients who underwent TIPS (P < 0.001). Previous splenectomy (OR 0.13, 95% CI 0.02-0.76, P = 0.024) and patency status of TIPS (OR 20.8, 95% CI 3.0-141.8, P = 0.002) were the independent factors associated with PVT disappearance. The 1- and 2-year rebleeding rates were, respectively, 44.6% and 59.0% in the EBL group, and 12.5% and 25.2% in the TIPS group (P = 0.002). The 1- and 2-year survival rates were, respectively, 95.7% and 85.2% in the EBL group, and 96% and 78.7% in the TIPS group (P = 0.203). The MELD score was the only independent predictive factor for survival (HR 1.73, 95% CI 1.27-2.37, P = 0.001). Compared with EBL, TIPS contributed to PVT improvement and reduced the risk of rebleeding without providing a survival benefit for patients with PVT.

Pretransplant Portal Vein Recanalization-Transjugular Intrahepatic Portosystemic Shunt in Patients With Complete Obliterative Portal Vein Thrombosis

BACKGROUND

Chronic, obliterative portal vein (PV) thrombosis (PVT) represents a relative contraindication to liver transplantation (LT) in some centers. When PV thromboembolectomy is not feasible, alternative techniques (portacaval hemitransposition, portal arterialization, multivisceral transplantation) are associated with suboptimal outcomes. In cases where a chronically thrombosed PV has become obliterated, we developed PV recanalization (PVR)-transjugular intrahepatic portosystemic shunt (TIPS) to potentiate LT. We evaluated the impact of PVR-TIPS on liver function, transplant eligibility, and long-term outcomes after LT.

METHODS

Forty-four patients with chronic obliterative main PVT were identified during our institutional LT selection committee. After joint imaging review by transplant surgery/radiology, these patients underwent PVR-TIPS to potentiate transplant eligibility. Patients were followed by hepatology/transplant until LT, and ultimately in posttransplant clinic. The TIPS venography and serial ultrasound/MRI were used subsequently to document PV patency.

RESULTS

The main PV (MPV) was completely thrombosed in 17 of 44 (39%) patients; near complete (>95%) occlusion was noted in 27 of 44 (61%) patients. Direct transhepatic and transsplenic punctures were required in 11 of 43 (26%) and 3 of 43 (7%) cases, respectively. Technical success was 43 of 44 (98%) cases. At PVR-TIPS completion, persistence of MPV thrombus was noted in 33 of 43 (77%) cases. One-month TIPS venography demonstrated complete resolution of MPV thrombosis in 22 of 29 (76%) without anticoagulation. Thirty-six patients were listed for transplantation; 18 (50%) have been transplanted. Eighty-nine percent MPV patency rate and 82% survival were achieved at 5 years.

CONCLUSIONS

The PVR-TIPS may be considered for patients with obliterative PVT who are otherwise appropriate candidates for LT. The high rate of MPV patency post-TIPS placement suggests flow reestablishment as the dominant mechanism of thrombus resolution.

Is Post-TIPS Anticoagulation Therapy Necessary in Patients with Cirrhosis and Portal Vein Thrombosis? A Randomized Controlled Trial

Purpose To determine whether posttransjugular intrahepatic portosystemic shunt (TIPS) placement anticoagulation therapy could benefit patients with cirrhosis and portal vein thrombosis (PVT) from the perspective of a change in portal vein patency status and clinical outcomes. Materials and Methods The study was approved by the institutional review board, and informed consent was obtained from each patient. From October 2012 to February 2014, patients with cirrhosis and PVT who underwent TIPS placement were randomly assigned to the anticoagulation therapy or control group. All patients were followed at 1, 3, 6, and 12 months after the TIPS procedure. Outcome measures were a change of portal vein patency status and clinical measures including gastrointestinal rebleeding, shunt dysfunction, hepatic encephalopathy, and survival. Student t test, χ(2) test, Fisher exact test, Mann-Whitney U test, and logistical regression were applied where appropriate. Results A total of 64 patients were enrolled in the study, with 31 allocated to the anticoagulation group and 33 allocated to the control group. Overall, thrombi were improved in 61 patients (96.8%) after the procedure. PVT recanalization (ie, complete disappearance; reconstruction of cavernous transformation) was achieved in 26 patients (83.9%) in the anticoagulation therapy group and in 23 (71.8%) patients in tthe control group (P = .252). The presence of a superior mesenteric vein thrombus may help predict recanalization failure (unadjusted relative risk = 0.243; 95% confidence interval: 0.070, 0.843; P = .026). Clinical outcomes were also similar between the two groups. Conclusion Anticoagulation therapy may not be necessary in certain patients with PVT because TIPS placement alone can achieve a high persistent recanalization rate. (©) RSNA, 2015.

Therapy Algorithm for Portal Vein Thrombosis in Liver Cirrhosis: The Internist's Point of View

BACKGROUND

Treatment of non-malignant portal vein thrombosis (PVT) in patients with cirrhosis has been neglected in the past because of the fear of bleeding complications when using anticoagulation and due to the technical difficulties associated with the implantation of the transjugular intrahepatic portosystemic shunt (TIPS). However, PVT has a negative impact on outcome and compromises liver transplantation, warranting treatment by using anticoagulation and TIPS.

METHODS

This review considers studies on the treatment of PVT in cirrhosis published in the last 10 years. Unfortunately, many of these studies are limited by their retrospective design and a small sample size.

RESULTS

Anticoagulation using low-molecular-weight heparin (LMWH) or vitamin K antagonists is effective in the treatment of patients with limited and recent PVT, resulting in a recanalization in up to 50% of the patients. TIPS (plus local measures) results in a recanalization of up to 100% and reduces the rebleeding rate considerably in patients with recent or chronic PVT.

CONCLUSION

Based on the presently limited knowledge, a therapy algorithm is suggested favouring the TIPS as a first-line treatment for PVT in patients with symptomatic portal hypertension. Patients with thus far asymptomatic portal hypertension may first receive anticoagulation, preferably using LMWH. If these patients have a condition where anticoagulation is not promising (complete, extended, chronic PVT) or ineffective, or if they are candidates for liver transplantation, the TIPS may be implanted without delay.

Portal vein thrombosis in cirrhosis: Controversies and latest developments

Portal vein thrombosis (PVT) is encountered in liver cirrhosis, particularly in advanced disease. It has been a feared complication of cirrhosis, attributed to significant worsening of liver disease, poorer clinical outcomes and potential inoperability at liver transplantation; also catastrophic events such as acute intestinal ischaemia. Optimal management of PVT has not yet been addressed in any consensus publication. We review current literature on PVT in cirrhosis; its prevalence, pathophysiology, diagnosis, impact on the natural history of cirrhosis and liver transplantation, and management. Studies were identified by a search strategy using MEDLINE and Google Scholar. The incidence of PVT increases with increasing severity of liver disease: less than 1% in well-compensated cirrhosis, 7.4%-16% in advanced cirrhosis. Prevalence in patients undergoing liver transplantation is 5%-16%. PVT frequently regresses instead of uniform thrombus progression. PVT is not associated with increased risk of mortality. Optimal management has not been addressed in any consensus publication. We propose areas for future research to address unresolved clinical questions.

Portal vein thrombosis

Portal vein thrombosis (PVT) is a rare event in the general medical setting that commonly complicates cirrhosis with portal hypertension, and can also occur with liver tumors. The diagnosis is often incidental when a thrombus is found in the portal vein on imaging tests. However, PVT may also present with clinical symptoms and can progress to life-threatening complications of ischemic hepatitis, liver failure, and/or small intestinal infarction. This article reviews the pathophysiology of this disorder, with a major focus on PVT in patients with cirrhosis, and presents detailed guidelines on optimal diagnostic and therapeutic strategies.

Interventional treatment for portal venous occlusion after liver transplantation: long-term follow-up results

Portal vein (PV) occlusion after liver transplant is an uncommon clinical situation, and percutaneous interventional treatment for this condition has not been widely described. The aim of this study was to evaluate the long-term treatment effect of interventional treatment for PV occlusion after liver transplantation (LT). Follow-up data of 13 patients who received interventional treatment for PV occlusion after LT between July 2007 and April 2013 were analyzed. Of these, 10 patients had portal hypertension-related signs and symptoms. Percutaneous balloon angioplasty and stent placement were performed, with percutaneous thrombolysis treatment as appropriate. Embolization therapy was required for significant collateral circulation. Technical and clinical success, complications, and patency of PV were analyzed. Both technical and clinical success was achieved in 11 of the 13 patients (84.6%). Direct portogram showed limited PV occlusion in 7 patients and extensive PV occlusion in 4 patients. The former underwent balloon angioplasty followed by stent placement, while the latter underwent balloon angioplasty followed by stent placement and additional percutaneous thrombolysis treatment. Embolization therapy for collateral circulation was performed in all 4 patients with extensive PV occlusion and 1 patient with limited PV occlusion. All stents remained patency during the follow-up (28.5 ± 6.8 months). No portal hypertension-related symptoms reoccurred during follow-up. In conclusion, interventional treatment for PV occlusion after LT showed a high success rate and good long-term results. Comprehensive interventional treatment should be used for extensive PV occlusion.

Rational classification of portal vein thrombosis and its clinical significance

Portal vein thrombosis (PVT) is commonly classified into acute (symptom duration <60 days and absence of portal carvernoma and portal hypertension) and chronic types. However, the rationality of this classification has received little attention. In this study, 60 patients (40 men and 20 women) with PVT were examined using contrast-enhanced computed tomography (CT). The percentage of vein occlusion, including portal vein (PV) and superior mesenteric vein (SMV), was measured on CT image. Of 60 patients, 17 (28.3%) met the criterion of acute PVT. Symptoms occurred more frequently in patients with superior mesenteric vein thrombosis (SMVT) compared to those without SMVT (p<0.001). However, there was no significant difference in PV occlusion between patients with and without symptoms. The frequency of cavernous transformation was significantly higher in patients with complete PVT than those with partial PVT (p<0.001). Complications of portal hypertension were significantly associated with cirrhosis (p<0.001) rather than with the severity of PVT and presence of cavernoma. These results suggest that the severity of PVT is only associated with the formation of portal cavernoma but unrelated to the onset of symptoms and the development of portal hypertension. We classified PVT into complete and partial types, and each was subclassified into with and without portal cavernoma. In conclusion, neither symptom duration nor cavernous transformation can clearly distinguish between acute and chronic PVT. The new classification system can determine the pathological alterations of PVT, patency of portal vein and outcome of treatment in a longitudinal study.

Management of portal vein thrombosis in liver cirrhosis

Portal vein thrombosis (PVT) is a fairly common complication of liver cirrhosis. Importantly, occlusive PVT might influence the prognosis of patients with cirrhosis. Evidence from a randomized controlled trial has shown that anticoagulation can prevent the occurrence of PVT in patients with cirrhosis without prior PVT. Evidence from several case series has also demonstrated that anticoagulation can achieve portal vein recanalization in patients with cirrhosis and PVT. Early initiation of anticoagulation therapy and absence of previous portal hypertensive bleeding might be positively associated with a high rate of portal vein recanalization after anticoagulation. However, the possibility of spontaneous resolution of partial PVT questions the necessity of anticoagulation for the treatment of partial PVT. In addition, a relatively low recanalization rate of complete PVT after anticoagulation therapy suggests its limited usefulness in patients with complete PVT. Successful insertion of a transjugular intrahepatic portosystemic shunt (TIPS) not only recanalizes the thrombosed portal vein, but also relieves the symptomatic portal hypertension. However, the technical difficulty of TIPS potentially limits its widespread application, and the risk and benefits should be fully balanced. Notably, current recommendations regarding the management of PVT in liver cirrhosis are insufficient owing to low-quality evidence.

Portal vein thrombosis and liver transplantation: implications for waiting list period, surgical approach, early and late follow-up

Portal vein thrombosis (PVT) is a well-known and relatively common complication of liver cirrhosis. In the past, PVT was considered as a contraindication for liver transplantation (LT). To characterize prevalence, risk factors, perioperative management and outcome of PVT in the setting of LT, the English literature published between 1991 and 2011 was reviewed. Of 6807 articles, 280 were selected, and 39 experiences were analyzed in detail (methodology, type and duration of treatments, peri-operative management, strategy to avoid recurrence, strengths and weaknesses, Oxford evidence level, citations). 3/39 studies were prospective; 9/39 were based on prospectively recorded databases; no studies of 1, 2a, 3a level of evidence were present; 5/39 were recognized as level 2b, 23/39 as level 3b, and 8/39 as level 4. High complication rate has been reported with consequent effect on graft and patient survival. Overall, PVT presents today good results similar to those obtained in patients without PVT undergoing LT even if they require a higher transfusion number and a longer ICU/hospital stay. Reported cases were retrospectively stratified according to Yerdel classification. Grade 1-2 patients (76%) do well with eversion thromboendovenectomy, resection of damaged vein and porto-portal anastomosis. Results of patients with grade 3-4 (24%) are inferior, however data on outcome in this subsets are fragmented and do not allow a reliable analysis. Moreover, results obtained in grade 3-4 cases are better in transplant centers with large specific experience. The small number of reports suggests caution. The role of anticoagulant treatment is still debated. Although in cirrhotics with PVT LT remains a demanding procedure, PVT should not be considered a contraindication anymore.

Hepatic Artery Embolization prior to En Bloc Resection of an Encased Common Hepatic Artery in Adenocarcinoma of the Head of the Pancreas

A 64-year-old female patient with adenocarcinoma of the head of the pancreas with encasement of the common hepatic artery and portal vein stenosis was reexplored after six cycles of gemcitabine (1000 mg/m(2)). Prior to surgery, the patient underwent balloon dilation and stenting of the portal vein in addition to successful coil embolisation of the common hepatic artery, proper hepatic artery, and proximal gastroduodenal artery. After embolisation, a pylorus-preserving pancreaticoduodenectomy was performed with resection of the common hepatic artery and portal vein confluens. Pathological examination showed a moderately differentiated pT3N0 (Stage IIa, TNM 7th edition) tumor with negative section margins. We show with this case that in selected cases of periampullary cancer with encasement of the common hepatic artery, it is technically feasible to perform pancreaticoduodenectomy with hepatic artery resection and negative surgical margins. Nevertheless, the oncological benefit of extended arterial resections remains controversial.

Transjugular intrahepatic portosystemic shunt for maintenance of portal venous patency in liver transplant candidates

Maintenance of portal venous patency is vital to liver transplant candidates, as the presence of portal vein thrombosis (PVT) adversely impacts clinical outcomes by increasing surgical complexity and decreasing postoperative survival. By enhancing portal venous blood flow, transjugular intrahepatic portosystemic shunt (TIPS) creation may enable clearance of PVT and preservation of portal venous patency in cirrhotic patients. Herein, we describe four cases in which TIPS produced and sustained an open portal venous system in liver transplant candidates with partial PVT. All patients demonstrated rapid and effective flow-enabled clearance of clot and intermediate to long-term preservation of portal venous flow. On this basis, we propose that maintenance of portal venous patency in liver transplant candidates with partial PVT represents a developing indication for TIPS.

Efficacy of transjugular intrahepatic portosystemic shunt to prevent total portal vein thrombosis in cirrhotic patients awaiting for liver transplantation

INTRODUCTION

Complete portal vein thrombosis (PVT) may complicate orthotopic liver transplantation (OLT), increasing its technical difficulty and the transfusion requirements and as well as affecting survival in some cases. Transjugular intrahepatic portosystemic shunt (TIPS) prevents total portal vein occlusion in patients with partial PVT.

OBJECTIVE

We aimed to assess the efficacy and safety of TIPS to prevent total portal vein occlusion among patients listed for OLT.

PATIENTS AND METHODS

We analyzed the clinical records of 15 consecutive patients with partial PVT who underwent TIPS before OLT. The control group consisted of 8 transplanted patients without TIPS but partial PVT diagnosed before OLT. Portal vein patency at surgery, ischemia time, and transfusion requirements during OLT, and survival thereafter were compared between both groups. The main complications were also compared: mortality after TIPS (from TIPS placement to OLT), intraoperative technical complications, and technical complications during the 6 months after OLT.

RESULTS

Clinical characteristics at the time of OLT were similar between the groups. No relevant complications were observed after TIPS; all patients underwent transplantation. One- and 5-year actuarial survival rates were similar in both groups (92% and 85% in TIPS-group versus 100 and 75% in the control group, respectively). No differences in transfusion requirement, duration of ischemia, and frequency of technical complications during and after OLT were observed between the groups. The portal vein was patent at surgery in all TIPS patients and 4 of 8 (50%) in the control group (P = .008).

CONCLUSION

TIPS may prevent PVT in liver transplantation candidates with partial PVT.