Treatment of acute portal vein thrombosis by nontraditional anticoagulation

Portal vein thrombosis

Portal vein thrombosis is an important cause of portal hypertension. PVT occurs in association with cirrhosis or as a result of malignant invasion by hepatocellular carcinoma or even in the absence of associated liver disease. With the current research into its genesis, majority now have an underlying prothrombotic state detectable. Endothelial activation and stagnant portal blood flow also contribute to formation of the thrombus. Acute non-cirrhotic PVT, chronic PVT (EHPVO), and portal vein thrombosis in cirrhosis are the three main variants of portal vein thrombosis with varying etiological factors and variability in presentation and management. Procoagulant state should be actively investigated. Anticoagulation is the mainstay of therapy for acute non-cirrhotic PVT, with supporting evidence for its use in cirrhotic population as well. Chronic PVT (EHPVO) on the other hand requires the management of portal hypertension as such and with role for anticoagulation in the setting of underlying prothrombotic state, however data is awaited in those with no underlying prothrombotic states. TIPS and liver transplant may be feasible even in the setting of PVT however proper selection of candidates and type of surgery is warranted. Thrombolysis and thrombectomy have some role. TARE is a new modality for management of HCC with portal vein invasion.

Progress in treatment of nontumoral portal vein thrombosis in liver cirrhosis

Portal vein thrombosis (PVT) is not uncommon in patients with liver cirrhosis, and it increases the risk of gastroesophageal hemorrhage. At present, pharmacological treatment is the preferred selection of management of PVT. Studies have shown that anticoagulation therapy does not increase the risk of gastrointestinal bleeding. Therefore, patients having indications should be given anticoagulation therapy as early as possible. When patients fail to respond to anticoagulation therapy, interventional therapy or surgery may be considered. This article reviews the recent knowledge about the treatment of PVT and discusses the progress in treatment of nontumoral PVT in liver cirrhosis.

How I treat splanchnic vein thrombosis

Antithrombotic treatment of splanchnic vein thrombosis (SVT) is a clinical challenge. Depending on the site of thrombosis, patients are at risk of developing liver insufficiency, portal hypertension, or bowel infarction and may experience recurrence in both the splanchnic veins and other vein segments. To prevent recurrence, anticoagulant therapy should be started as soon as possible after diagnosis and is often continued for an indefinite period of time. However, active bleeding is not infrequent at the time of SVT diagnosis, and major risk factors for bleeding, such as esophageal varices or a low platelet count, are frequently present in these patients. In real-world clinical practice, a proportion of SVT patients are left untreated because the risks associated with anticoagulant therapy are felt to exceed its benefits. However, the majority of patients receive anticoagulant drugs, with heterogeneous timing of initiation, drug choice, and dosages. Evidence to drive treatment decisions is limited because no randomized controlled trials have been carried out in these patients. This review provides practical guidance for the use of anticoagulant drugs in patients presenting with SVT, including symptomatic as well as incidentally detected events.

Elevated serum erythropoietin in a patient with polycythaemia vera presenting with Budd-Chiari syndrome

Polycythaemia vera (PV) is a clonal disorder of bone marrow stem cells characterised by erythrocytosis. Diagnosis of PV requires exclusion of secondary causes of polycythaemia. It has been held that an elevated erythropoietin (Epo) level strongly indicates secondary erythrocytosis and excludes PV diagnosis, to the extent that the reduced serum Epo level is currently listed as a minor criterion in the WHO classification scheme for PV. However, patients with PV who co-present with Budd-Chiari syndrome have been documented with elevated serum Epo levels. For these patients, identification of the Janus kinase 2 (JAK2) V617F point mutation along with the transient nature of the Epo elevation provides certainty of PV diagnosis, as illustrated by the proband. In this case report, the patient's positive response to cytoreductive therapy (hydroxyurea 500 mg daily) and phlebotomy (750 mL over three phlebotomies) further supports validity of PV diagnosis with elevated Epo. The patient remains on rivaroxaban (Xarelto) for treatment of her portal vein thrombosis.

Optimizing risk stratification in portal vein thrombosis after splenectomy and its primary prophylaxis with antithrombin III concentrates and danaparoid sodium in liver cirrhosis with portal hypertension

BACKGROUND

Decreased antithrombin III (ATIII) activity and large splenic vein diameter (SVD) are risk factors for portal vein thrombosis (PVT) after splenectomy in liver cirrhosis with portal hypertension. Antithrombin III concentrates can prevent PVT. This study was designed to stratify risks for PVT after splenectomy in cirrhotic patients and to develop prophylactic protocols for PVT.

STUDY DESIGN

In 53 patients (testing cohort), the cutoff level of preoperative ATIII activity (≤60%) was evaluated for administration of ATIII concentrates. Antithrombin III activity and SVD were re-evaluated as criteria for prophylaxis of PVT. In 57 patients (validation cohort), the risk stratification of PVT and prophylactic protocols were validated.

RESULTS

In the testing cohort, 10 (19%) of 53 patients had PVT. Risk level of PVT was stratified and prophylactic protocols were developed. Patients at low risk (ATIII activity ≥70% and SVD <10 mm) were not treated; those at high risk (ATIII activity <70% or SVD ≥10 mm) received ATIII concentrates (1,500 U/day) for 3 days; and those at highest risk (SVD ≥15 mm) received ATIII concentrates for 3 days, followed by danaparoid sodium (2,500 U/day) for 14 days and warfarin. In the validation cohort, 0 of 14 low-risk and 2 of 32 high-risk patients had PVT. Although 8 of 11 patients at highest risk had temporary PVT, it disappeared within 3 months postoperatively. Finally, only 2 (3.5%) of 57 patients had PVT.

CONCLUSIONS

Risk stratification of PVT after splenectomy and prophylaxis with ATIII concentrates and danaparoid sodium dramatically reduced the incidence of PVT.