Management of splanchnic vein thrombosis

Portal Vein Thrombosis in Patients Without Cirrhosis: Current Practical Approaches and Treatment Strategies

Portal vein thrombosis in non-cirrhotic individuals, although uncommon, is an increasingly explored condition that affects mainly young people, consequently representing a significant disease burden. Reports primarily including western European populations have recently shed light regarding the pathophysiology, risk factors, natural history, treatment, and prognosis of this entity. Underlying predisposing conditions are documented in ~70% of cases, encompassing local risk factors, inherited and acquired thrombophilia, cancer, and systemic inflammatory conditions. Non-cirrhotic portal vein thrombosis can cause significant portal hypertension in the acute setting, but, more frequently, significant portal hypertension-related complications arise when the condition becomes chronic and portosystemic collaterals develop, increasing the risk for variceal bleeding and ascites. The diagnostic approach to screen for underlying thrombophilia remains a challenge, and recommendations in this regard, although scarce and backed by scarce evidence, have changed notably in the last years, leaning toward a universal screen in patients who develop this condition without a clear provoking factor. Recently, studies have shown that long-term anticoagulation may be appropriate even in the absence of clear provoking factors or underlying thrombophilia. Future studies should address which patients may benefit from this approach, which patients may not need it, and what the most appropriate strategies are to approach patients who do not recover portal vein patency with anticoagulation to further prevent portal hypertension-related complications.

Incidence and Management of Splanchnic Vein Thrombosis in Pancreatic Diseases

Splanchnic vein thrombosis (SVT) in pancreatic disease has a 20%-30% incidence rate, leading to increased mortality and complication rates. Therefore, the aim of this review is to summarize recent evidence about the incidence, risk factors, and management of pancreatic cancer, pancreatic cystic neoplasm-, and pancreatitis-related SVT. Doppler ultrasound should be the first imaging choice, followed by contrast-enhanced computed tomography or magnetic resonance imaging. Data regarding SVT treatment in acute pancreatitis and pancreatic cancer are scarce; however, for venous thromboembolism treatment, direct oral anticoagulants and low molecular weight heparin have been effective. Further trials must investigate the length of anticoagulant treatment and the need for interventional radiological procedures.

Porto-sinusoidal vascular liver disorder with portal hypertension: Natural history and long-term outcome

BACKGROUND & AIMS

Current knowledge of the natural history of patients with porto-sinusoidal vascular disorder (PSVD) is derived from small studies. The aim of the present study was to determine the natural history of PSVD and prognostic factors in a large multicenter cohort of patients.

METHODS

We performed a retrospective study on patients with PSVD and signs of portal hypertension (PH) prospectively registered in 27 centers.

RESULTS

A total of 587 patients were included, median age of 47 years and 38% were women. Four-hundred and one patients had an associated condition, which was graded as severe in 157. Median follow-up was 68 months. At diagnosis, 64% of patients were asymptomatic while 36% had a PH-related complication: PH-related bleeding in 112 patients, ascites in 117, and hepatic encephalopathy in 11. In those not presenting with bleeding, the incidence of first bleeding was 15% at 5 years, with a 5-year rebleeding rate of 18%. The 5-year cumulative incidence of new or worsening ascites was 18% and of developing portal vein thrombosis was 16%. Fifty (8.5%) patients received a liver transplantation and 109 (19%) died, including 55 non-liver-related deaths. Transplant-free survival was 97% and 83% at 1 and 5 years, respectively. Variables independently associated with transplant-free survival were age, ascites, serum bilirubin, albumin and creatinine levels at diagnosis and severe associated conditions. This allowed for the creation of a nomogram that accurately predicted prognosis.

CONCLUSIONS

The prognosis of PSVD is strongly determined by the severity of the associated underlying conditions and parameters of liver and renal function.

IMPACT AND IMPLICATIONS

Porto-sinusoidal vascular liver disorder (PSVD) is a rare entity that usually affects young people, frequently causes severe complications of portal hypertension, and may reduce life expectancy. To date, there is scarce information regarding its clinical manifestations, natural history and prognostic factors. The present study, including the largest number of patients with PSVD reported so far, shows that overall, when managed at centers of expertise, the prognosis of patients with PSVD is good, with LT-free survival rates of 83% and 72% at 5 and 10 years, respectively. Presence and severity of an underlying associated condition, presence of ascites, age and bilirubin, albumin and creatinine levels were associated with poor prognosis. These results are important to know for hepatologists. A final model combining these parameters enabled development of a nomogram that predicts prognosis with good discrimination and calibration capacity and can be easily applied in clinical practice.

Abdominal surgery in patients with chronic noncirrhotic extrahepatic portal vein obstruction: A multicenter retrospective study

BACKGROUND AND AIMS

In patients with noncirrhotic chronic extrahepatic portal vein obstruction (EHPVO), data on the morbimortality of abdominal surgery are scarce.

APPROACH AND RESULTS

We retrospectively analyzed the charts of 76 patients (78 interventions) with EHPVO undergoing abdominal surgery within the Vascular Disease Interest Group network. Fourteen percent of the patients had ≥1 major bleeding (unrelated to portal hypertension) and 21% had ≥1 Dindo-Clavien grade ≥3 postoperative complications within 1 month after surgery. Fifteen percent had ≥1 portal hypertension-related complication within 3 months after surgery. Three patients died within 12 months after surgery. An unfavorable outcome (ie, ≥1 abovementioned complication or death) occurred in 37% of the patients and was associated with a history of ascites and with nonwall, noncholecystectomy surgical intervention: 17% of the patients with none of these features had an unfavorable outcome, versus 48% and 100% when one or both features were present, respectively. We then compared 63/76 patients with EHPVO with 126 matched (2:1) control patients without EHPVO but with similar surgical interventions. As compared with control patients, the incidence of major bleeding ( p <0.001) and portal hypertension-related complication ( p <0.001) was significantly higher in patients with EHPVO, but not that of grade ≥3 postoperative complications nor of death. The incidence of unfavorable postoperative outcomes was significantly higher in patients with EHPVO than in those without (33% vs. 18%, p =0.01).

CONCLUSIONS

Patients with EHPVO are at high risk of major perioperative or postoperative bleeding and postoperative complications, especially in those with ascites or undergoing surgery other than wall surgery or cholecystectomy.

Thrombotic, Cardiovascular, and Microvascular Complications of Myeloproliferative Neoplasms and Clonal Hematopoiesis (CHIP): A Narrative Review

The most common causes of morbidity and mortality in the myeloproliferative neoplasms (MPNs), with the exception of myelofibrosis, are venous and arterial thrombosis, as well as more recently discovered cardiovascular disease (CVD). Clonal hematopoiesis of indeterminate potential (CHIP) is the subclinical finding in an individual of somatic mutations that are also found in clinically overt MPNs and other myeloid malignancies. The prevalence of "silent" CHIP increases with age. CHIP can transform into a clinically overt MPN at an estimated rate of 0.5 to 1% per year. It is likely, therefore, but not proven, that many, if not all, MPN patients had antecedent CHIP, possibly for many years. Moreover, both individuals with asymptomatic CHIP, as well as clinically diagnosed patients with MPN, can develop thrombotic complications. An unexpected and remarkable discovery during the last few years is that even CHIP (as well as MPNs) are significant, independent risk factors for CVD. This review discusses up-to-date information on the types of thrombotic and cardiovascular complications that are found in CHIP and MPN patients. A systemic inflammatory state (that is often subclinical) is most likely to be a major mediator of adverse reciprocal bone marrow-cardiovascular interplay that may fuel the development of progression of MPNs, including its thrombotic and vascular complications, as well as the worsening of cardiovascular disease, possibly in a "vicious cycle". Translating this to clinical practice for hematologists and oncologists who treat MPN patients, attention should now be paid to ensuring that cardiovascular risk factors are controlled and minimized, either by the patient's cardiologist or primary care physician or by the hematologist/oncologist herself or himself. This review is intended to cover the clinical aspects of thrombosis and cardiovascular complications in the MPN, accompanied by pathobiological comments.

GSDMD-Dependent Neutrophil Extracellular Traps Mediate Portal Vein Thrombosis and Associated Fibrosis in Cirrhosis

Portal vein thrombosis (PVT) is a challenging and controversial complication of cirrhosis. Experimental models that reproduce cirrhotic PVT and effective pharmacological therapies are limited. We aimed to investigate the nature course and mechanisms of PVT in cirrhosis. A novel PVT model was developed via two-step total portal vein ligation in healthy and thioacetamide (TAA)-cirrhotic rats. Circulating and liver-infiltrating neutrophils were isolated from individuals with cirrhosis to examine neutrophil extracellular traps (NETs) and explore their unique characteristics and implications in PVT-associated fibrosis in cirrhosis. We further validated macrophage-myofibroblast transition (MMT) via multiplex immunofluorescence and single-cell sequencing. In the experimental model, cirrhosis promoted PVT development and portal vein intimal thickening. Interestingly, cirrhosis promoted spontaneous resolution of PVT due to instability of thrombus structure, along with pulmonary and intrahepatic clots. NETs-MMT mediate cirrhotic PVT and PVT-associated fibrosis, including fibrotic thrombus remodeling and increased hepatic collagen deposition. Mechanistically, caspase-4-dependent activation of neutrophils and GSDMD mediated the formation of NETs. The extracellular DNA of NETs promoted TGF-β1/Smad3-driven MMT. Inhibiting GSDMD with disulfiram suppressed cirrhotic PVT and prevented associated fibrosis. The cirrhotic PVT model reflected the following three main characteristics of cirrhotic PVT: spontaneous resolution, immunothrombosis, and intimal fibrosis. Targeting NETs with GSDMD inhibitors may serve as a new therapeutic concept to treat cirrhotic PVT.

[Coagulation disorders in liver cirrhosis - Diagnostics and management]

Patients with liver cirrhosis often exhibit complex alterations in their hemostatic system that can be associated with both bleeding and thrombotic complications. While prophylactic correction of abnormal coagulation parameters should be avoided, an individualized approach is recommended prior to invasive procedures, whereby specific preventive measures to stabilize hemostasis should be based on the periprocedural bleeding risk. While the haemostatic system of patients with compensated cirrhosis is often in a rebalanced haemostatic state due to a parallel decline in both pro- and anti-haemostatic factors, a decompensation of liver cirrhosis can lead to destabilization of this fragile equilibrium. Since conventional coagulation tests do not adequately capture the complex changes in the hemostatic system in cirrhosis, functional analysis methods such as viscoelastic tests or thrombin generation assays can be used for evaluating the coagulation status. This review describes the underlying pathophysiological changes in the hemostatic system in liver cirrhosis, provides an overview of diagnostic methods and discusses therapeutic measures in case of bleeding and thrombotic complications.

[Portosinusoidal vascular disorder: A paradigm shift]

The term portosinusoidal vascular disorder (PSVD) refers to a clinical-pathological entity that encompasses those patients with intrahepatic vascular damage without cirrhosis at risk of developing severe complications of portal hypertension. Numerous systemic diseases, genetic disorders, and toxic agents have been associated with this pathology, making its diagnosis an important clinical challenge. The recent description of uniform diagnostic criteria and a better understanding of its pathophysiology will allow for better identification of patients, even in early stages of the disease. Although there is currently no effective etiological treatment available, early diagnosis allows for the development of preventive strategies for some severe complications of portal hypertension.

Transjugular Intrahepatic Portosystemic Shunt in Nonmalignant Noncirrhotic Portal Vein Thrombosis and Portosinusoidal Vascular Disorder

Transjugular intrahepatic portosystemic shunt (TIPS) emerges as a key treatment for portal hypertension (PH) complications. While international guidelines provide clear indications for its use in cirrhosis, empirical knowledge is notably scarcer in non-cirrhotic PH, particularly in nonmalignant noncirrhotic portal vein thrombosis (NNPVT) and in patients with portosinusoidal vascular disorder (PSVD). Patients afflicted by these rare diseases exhibit distinct clinical profiles compared to their cirrhotic counterparts, often characterized by a younger age, predominantly preserved hepatic functionality even in cases of severe PH, and a higher propensity for extensive splanchnic thrombosis, which intricately complicates TIPS placement, posing unique challenges for its creation. The objective of this review is to synthesize existing literature on the effectiveness, safety, specific indications, and clinical outcomes of TIPS in adult patients with NNPVT or PSVD, focusing also on the technical challenges of TIPS insertion in the presence of portal cavernoma.

[Splanchnic vein thrombosis]

Splanchnic vein thrombosis includes Budd-Chiari syndrome and portal vein thrombosis. These diseases share common features: (i) they are rare diseases and (ii) they can lead to portal hypertension and its complications. Budd-Chiari syndrome and portal vein thrombosis in the absence of underlying liver disease share many risk factors, the most common being myeloproliferative neoplasms. A rapid and comprehensive workup for thrombosis risk factors is necessary in these patients. Long-term anticoagulation is indicated in most patients. Portal vein thrombosis can also develop in patients with cirrhosis, and is associated with a worse course of cirrhosis. Indications for anticoagulation in patients with cirrhosis are increasing. Transjugular intrahepatic portosystemic shunt is a second-line procedure in this setting. Because of the rarity of these diseases, high-level evidence studies are rare. However, collaborative studies have provided a better understanding of their natural history and allowed to improve the management of these patients. This review focuses on the causes, diagnosis, and management of patients with Budd-Chiari syndrome, patients with portal vein thrombosis without underlying liver disease, and patients with cirrhosis and portal vein thrombosis.

Management of a complex transjugular intrahepatic portosystemic shunt dysfunction with endotipsitis through rotational thrombectomy

Transjugular intrahepatic portosystemic shunting (TIPS) is an established strategy for the management of complications of portal hypertension. Endoprosthetic infection ("endotipsitis") is a rare but serious and difficult-to-treat complication of TIPS placement. Here we report the occurrence of an infected thrombus complicating TIPS placement in a patient with extra-hepatic portal vein obstruction, recurrent variceal bleeding and portal biliopathy accompanied by recurrent cholangitis. Infected thrombotic material within TIPS could be removed only by employing rotational thrombectomy. This procedure revealed the presence of a biliary fistula which carried pathogens in the systemic circulation. The multiple episodes of sepsis did no longer recur following exclusion of the biliary fistula. This case highlights the possibility to use rotational thrombectomy for the management of complex cases of TIPS dysfunction.

A narrative review of acute pancreatitis-induced splanchnic vein thrombosis: from pathogenesis to clinical management

Acute pancreatitis-induced splanchnic vein thrombosis (APISVT) is an important sequela complication of acute pancreatitis, which may cause poor prognosis, such as severe gastrointestinal hemorrhage, bowel ischemic necrosis and liver failure. However, its mechanism remains uncertain, and there is not a general consensus on the management. In this study, we reviewed the latest academic publications in APISVT, and discussed its pathogenesis, clinical presentation, adverse outcome and treatment, especially focused on the role of anticoagulant therapy. It was indicated that anticoagulation therapy can significantly elevate thrombus recanalization and reduce the incidence of complications and mortality with no increase of bleeding. Actually, as most of these studies were retrospective analyses and prospective studies included small samples, the conclusion remains controversial. Thus, well-designed randomized controlled trials are urged to verify the effectiveness and safety of anticoagulation therapy for APISVT.

Effect of Direct Oral Anticoagulants in Patients with Splanchnic Vein Thrombosis: A Systematic Reviews and Meta-Analysis

BACKGROUND

Since several studies have examined the use of direct oral anticoagulants (DOACs) in treating patients with splanchnic vein thrombosis (SVT), we conducted a meta-analyses to assess the safety and efficacy of DOACs compared to vitamin K antagonists (VKAs) in this population.

METHODS

We conducted a comprehensive search using the PubMed, Embase, and Cochrane Library databases until June 2024. We used odds ratios (ORs) and 95% confidence intervals (CIs) as the effect measures to compare DOACs with VKAs.

RESULTS

A total of 9 observational studies were included. The pooled analysis revealed that a trend towards higher complete recanalization rates with DOACs (71.4%) compared to VKAs (55.3%), though not statistically significant (OR 1.95; 95%CI 0.70 to 5.44). For SVT extension, a significant effect was observed favoring DOACs (OR 0.12; 95%CI 0.03 to 0.54). No significant differences were found in other efficacy outcomes or safety outcomes, except for major bleeding, which was significantly lower with DOACs (OR 0.27; 95%CI 0.13 to 0.56).

CONCLUSION

DOACs are superior to VKAs in SVT extension and major bleeding, suggesting that DOACs may be a favorable treatment option in the treatment of SVT.

Insights into acute mesenteric ischaemia: an up-to-date, evidence-based review from a mesenteric stroke centre unit

Radiologists play a central role in the diagnostic and prognostic evaluation of patients with acute mesenteric ischaemia (AMI). Unfortunately, more than half of AMI patients undergo imaging with no prior suspicion of AMI, making identifying this disease even more difficult. A confirmed diagnosis of AMI is ideally made with dynamic contrast-enhanced CT but the diagnosis may be made on portal-venous phase images in appropriate clinical settings. AMI is diagnosed on CT based on the identification of vascular impairment and bowel ischaemic injury with no other cause. Moreover, radiologists must evaluate the probability of bowel necrosis, which will influence the treatment options.AMI is usually separated into different entities: arterial, venous, non-occlusive and ischaemic colitis. Arterial AMI can be occlusive or stenotic, the dominant causes being atherothrombosis, embolism and isolated superior mesenteric artery (SMA) dissection. The main finding in the bowel is decreased wall enhancement, and necrosis can be suspected when dilatation >25 mm is identified. Venous AMI is related to superior mesenteric vein (SMV) thrombosis as a result of a thrombophilic state (acquired or inherited), local injury (cancer, inflammation or trauma) or underlying SMV insufficiency. The dominant features in the bowel are hypoattenuating wall thickening with submucosal oedema. Decreased enhancement of the involved bowel suggests necrosis. Non-occlusive mesenteric ischaemia (NOMI) is related to impaired SMA flow following global hypoperfusion associated with low-flow states. There are numerous findings in the bowel characterised by diffuse extension. An absence of bowel enhancement and a thin bowel wall suggest necrosis in NOMI. Finally, ischaemic colitis is a sub-entity of arterial AMI and reflects localised colon ischaemia-reperfusion injury. The main CT finding is a thickened colon wall with fat stranding, which seems to be unrelated to SMA or inferior mesenteric artery lesions. A precise identification and description of vascular lesions, bowel involvement and features associated with transmural necrosis is needed to determine patient treatment and outcome.

Direct oral anticoagulants for the treatment of splanchnic vein thrombosis: A state of art

Splanchnic vein thrombosis (SVT) is a manifestation of venous thromboembolism in an unusual site. Portal, mesenteric, and splenic veins are the most common vessels involved in SVT which occurs mainly in patients with liver cirrhosis, although non-cirrhotic patients could be affected as well. Thrombosis of hepatic veins, also known as Budd-Chiari syndrome, is another manifestation of SVT. Prompt diagnosis and intervention are mandatory in order to increase the recalization rate and reduce the risk of thrombus progression and hypertensive complications. Traditional anticoagulation with heparin and vitamin-K antagonists is the treatment of choice in these cases. However, recent studies have shown promising results on the efficacy and safety of direct oral anticoagulants (DOACs) in this setting. Available results are mainly based on retrospective studies with small sample size, but first clinical trials have been published in the last years. This manuscript aims to provide an updated overview of the current evidence regarding the role of DOACs for SVT in both cirrhotic and non-cirrhotic patients.

Molecular Mechanisms Underlying Vascular Liver Diseases: Focus on Thrombosis

Vascular liver disorders (VLDs) comprise a wide spectrum of clinical-pathological entities that primarily affect the hepatic vascular system of both cirrhotic and non-cirrhotic patients. VLDs more frequently involve the portal and the hepatic veins, as well as liver sinusoids, resulting in an imbalance of liver homeostasis with serious consequences, such as the development of portal hypertension and liver fibrosis. Surprisingly, many VLDs are characterized by a prothrombotic phenotype. The molecular mechanisms that cause thrombosis in VLD are only partially explained by the alteration in the Virchow's triad (hypercoagulability, blood stasis, and endothelial damage) and nowadays their pathogenesis is incompletely described and understood. Studies about this topic have been hampered by the low incidence of VLDs in the general population and by the absence of suitable animal models. Recently, the role of coagulation imbalance in liver disease has been postulated as one of the main mechanisms linked to fibrogenesis, so a novel interest in vascular alterations of the liver has been renewed. This review provides a detailed analysis of the current knowledge of molecular mechanisms of VLD. We also focus on the promising role of anticoagulation as a strategy to prevent liver complications and to improve the outcome of these patients.

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.

Pathological and genomic features of myeloproliferative neoplasms associated with splanchnic vein thrombosis in a single-center cohort

Here, we reviewed clinical-morphological data and investigated mutational profiles by NGS in a single-center series of 58 consecutive MPN-SVT patients admitted to our hospital between January 1979 and November 2021. We identified 15.5% of PV, 13.8% of ET, 34.5% of PMF, 8.6% of SMF and 27.6% of MPN-U. Most cases (84.5%) carried JAK2V617F mutation, while seven patients were characterized by other molecular markers, namely MPL in four and CALR mutations in three cases. NGS was performed in 54 (93.1%) cases: the most frequent additional mutations were found in TET2 (27.8%) and DNMT3A (16.7%) genes, whereas 25 (46.3%) patients had no additional mutation. Cases with JAK2V617F homozygosity had a higher median number of additional mutations than those with low allele burden. More importantly, all cases of leukemic evolution were characterized by a higher median number of co-mutations, and a co-mutational pattern of high-risk lesions, such as truncating mutations of ASXL1, bi-allelic TP53 loss, and CSMD1 mutations. Nevertheless, no difference was found between cases with and without additional somatic mutations regarding fibrotic progression, SVT recurrence, other thrombo-hemorrhagic complications, or death. After a median follow-up of 7.1 years, ten deaths were recorded; fibrotic progression/leukemic evolution was ascertained in one (1.7%) and six (10.3%) patients, respectively, while 22 (37.9%) patients suffered from recurrent thrombosis. In conclusion, our data underline the importance of using NGS analysis in the management of MPN-related SVT as it can support the MPN diagnosis, particularly in "triple-negative" cases, and provide additional information with potential consequences on prognosis and therapeutic strategies.

Myeloproliferative neoplasms and splanchnic vein thrombosis: Contemporary diagnostic and therapeutic strategies

Myeloproliferative neoplasms (MPNs) are the most common etiologies of primary splanchnic vein thrombosis, present in almost forty percent of patients with Budd-Chiari syndrome or portal vein thrombosis. Diagnosis of MPNs can be difficult in these patients because key characteristics, such as elevated blood cell counts and splenomegaly, are confounded by portal hypertension or bleeding complications. In recent years, diagnostic tools have improved to provide more accurate diagnosis and classification of MPNs. Although bone marrow biopsy findings remain a major diagnostic criterion, molecular markers are playing an increasing role not only in diagnosis but also in better estimating prognosis. Therefore, though screening for JAK2V617F mutation should be the starting point of the diagnostic workup performed in all patients with splanchnic vein thrombosis, a multidisciplinary approach is needed to accurately diagnose the subtype of myeloproliferative neoplasm, recommend the useful additional tests (bone marrow biopsy, search for an additional mutation using targeted next-generation sequencing), and suggest the best treatment strategy. Indeed, providing a specific expert care pathway for patients with splanchnic vein thrombosis and underlying myeloproliferative neoplasm is crucial to determine the optimal management to reduce the risk of both hematological and hepatic complications.