Portal vein thrombosis: an overview of current treatment options

Portal vein thrombosis (PVT) is a splanchnic vascular disorder characterised by a recent or chronic thrombotic occlusion of the portal venous system. Its aetiology is miscellaneous, and its management is demanding since PVT can play a critical role as far as morbidity and mortality are concerned. Indeed, PVT can develop as a complication of portal hypertension (PH), in association or not with advanced chronic liver disease, and aggravate its clinical consequences such as variceal bleeding and ascites. Furthermore, a diagnosis of PVT in a non-cirrhotic context can potentially reveal a previously unknown hypercoagulable condition, requiring further diagnostic steps and specific treatment in addition to anticoagulation. In addition to established therapeutic approaches, new strategies, including newer pharmacological treatments and interdisciplinary invasive procedures, gain more attention and have been increasingly introduced into clinical practice. This review aims at discussing the current knowledge in terms of treatment options for PVT.

Transarterial embolization of acute iatrogenic hemorrhages: predictive factors for mortality and outcome

OBJECTIVE

Iatrogenic hemorrhages occur in 0.5-16% of medical procedures. A retrospective study was conducted to analyze technical and clinical outcome of transarterial embolization (TAE) used for acute iatrogenic hemorrhage and to identify factors predicting outcome.

METHODS

All patients undergoing TAE for acute iatrogenic bleeding from 2006 to 2013 were retrospectively analyzed. Primary end points were technical and clinical success or failure and 30 day mortality.

RESULTS

A total of 153 patients underwent 182 TAEs. Factors associated with clinical failure were lower blood hemoglobin concentration, use of higher number of units of red blood cell concentrate, TAE performed at night or weekend, embolization of more than one vessel, shock state before digital subtraction angiography (DSA), and intensive care before TAE. In multivariate analysis, independent factors for clinical success were hemoglobin concentration, number of units of red blood cell concentrate, and TAE of more than one vessel. Technical failure was associated with female gender, failure to detect signs of bleeding in DSA, TAE of more than one vessel, and shock state before DSA. Bleeding related to anticoagulation medication resulted in a significantly higher mortality rate compared with bleeding due to the remaining causes (30% vs 15%, p < 0.05).

CONCLUSION

Despite excellent technical success, the mortality rate was significant. The only factors affecting clinical success were bleeding intensity and extent of injury. Bleeding attributed to anticoagulation is related to high mortality and therefore requires special attention.

ADVANCES IN KNOWLEDGE

This study gives insights into morbidity and mortality of iatrogenic bleedings and the technical and clinical success rates of TAE in a large study population.

Reversal agents for direct oral anticoagulants: considerations for hospital physicians and intensivists

Direct oral anticoagulants (DOACs) include dabigatran etexilate, a direct thrombin inhibitor, and specific inhibitors of activated coagulation factor X (FXa; e.g. apixaban, betrixaban, edoxaban, rivaroxaban). DOACs are associated with lower rates of major and fatal bleeding events compared with warfarin. Clinicians may need to achieve rapid reversal of anticoagulation effects of the DOACs in an emergency setting. Idarucizumab and andexanet alfa, which reverse the anticoagulant effects of dabigatran and FXa inhibitors, respectively, are DOAC reversal agents available in the US. Other reversal agents (e.g. ciraparantag for heparins, DOACs) are in development. Alternative nonspecific agents (e.g. fresh frozen plasma, prothrombin complex concentrate) are available. Nonspecific prohemostatic agents can counteract the anticoagulant action of DOACs in emergency situations, when specific reversal agents are unavailable. However, specific reversal agents are efficacious and safe and should be preferred when available. In this review, we discuss practical issues in the initiation of DOAC therapy, situations where reversal may be needed, coagulation assays, reversal agents, and post-reversal complications in the context of published evidence and guidelines.

Position paper of the Italian Society of Internal Medicine (SIMI) on prophylaxis and treatment of venous thromboembolism in patients with cancer

Cancer patients are at high risk of developing thrombotic events, including venous thromboembolism (VTE) [deep venous thrombosis (DVT) and pulmonary embolism (PE)], and arterial thrombosis. DVT and PE represent the second leading cause of death in cancer patients; moreover, the development of thromboembolic events in cancer patients is linked to a greater need of hospitalization and frequency of side effects during treatment, in particular bleeding, and to an increased risk of recurrence during and following antithrombotic therapy. The thromboembolic risk may be different in different subgroups of cancer population, being highest in patients with metastatic disease, patients with pancreas, stomach, kidney or primary brain cancer, or during therapeutic interventions or surgery. This document focuses on several relevant topics including the epidemiology and pathogenesis of cancer-associated VTE, the current and future strategies of primary prevention and anticoagulant treatment, and the management of bleeding complications. The main literature data are discussed in detail, including, when available, evidence from randomized clinical trials and meta-analyses, international guidelines statements, the results of recently published trials comparing direct oral anticoagulants to low molecular weight heparin, and the design and aims of ongoing trials on prevention/treatment of cancer-associated VTE.

Evaluation of combined idarucizumab and prothrombin complex concentrate treatment for bleeding related to dabigatran in a lethal porcine model of double trauma

BACKGROUND

Idarucizumab (IDA) is approved for emergency reversal of dabigatran; prothrombin complex concentrates (PCCs) are recommended in the absence of specific antidote. The combined effects of IDA and PCC in trauma-related bleeding are unknown. The efficacy and safety of combined IDA + PCC were assessed in a lethal porcine model of double trauma under dabigatran anticoagulation.

STUDY DESIGN AND METHODS

Male pigs (n = 28) received oral dabigatran etexilate (30 mg/kg bid) for 3 days; a non-dabigatran control group (n = 7) received placebo. On Day 4, dabigatran-treated animals were randomized 1:1:1:1 to receive placebo + placebo (dabigatran-treated control), IDA + PCC (60 mg/kg + 50 IU/kg), PCC + IDA, or IDA + IDA. Trauma was induced at t = 0 (bilateral femur fractures and blunt liver injury) and t = 60 minutes (second blunt liver injury). Study treatment was administered 15 minutes after each trauma. Animals were monitored for 5 hours or until death.

RESULTS

Total blood loss in IDA + PCC, PCC + IDA, and IDA + IDA was 1673 ± 370, 1981 ± 361, and 1417 ± 135 mL, respectively, with 100% survival at 5 hours. Blood loss in dabigatran-treated controls was 4427 ± 162 mL with 100% mortality. With IDA + IDA, plasma coagulation parameters and thrombin generation were similar to non-dabigatran control group levels after the second dose and remained stable over time. In the IDA + PCC and PCC + IDA groups, thrombin generation and d-dimer levels after the second dose were higher than with IDA + IDA. No thromboembolic complications were found.

CONCLUSION

IDA and PCC are effective in treating trauma-related bleeding with dabigatran anticoagulation. IDA is preferable for emergency reversal of dabigatran, but PCC may be valuable when the anticoagulant is unknown.

International clinical practice guidelines including guidance for direct oral anticoagulants in the treatment and prophylaxis of venous thromboembolism in patients with cancer

Venous thromboembolism (VTE) is the second leading cause of death in patients with cancer. These patients are at an increased risk of developing VTE and are more likely to have a recurrence of VTE and bleeding while taking anticoagulants. Management of VTE in patients with cancer is a major therapeutic challenge and remains suboptimal worldwide. In 2013, the International Initiative on Thrombosis and Cancer (ITAC-CME), established to reduce the global burden of VTE in patients with cancer, published international guidelines for the treatment and prophylaxis of VTE and central venous catheter-associated thrombosis. The rapid global adoption of direct oral anticoagulants for management of VTE in patients with cancer is an emerging treatment trend that needs to be addressed based on the current level of evidence. In this Review, we provide an update of the ITAC-CME consensus recommendations based on a systematic review of the literature ranked according to the Grading of Recommendations Assessment, Development, and Evaluation scale. These guidelines aim to address in-hospital and outpatient cancer-associated VTE in specific subgroups of patients with cancer.

Idarucizumab: A Review as a Reversal Agent for Dabigatran

Idarucizumab (Praxbind(®)), a humanized monoclonal antibody, is a specific reversal agent for the direct oral thrombin inhibitor dabigatran, available as its prodrug dabigatran etexilate (Pradaxa(®)). Idarucizumab is approved in several countries (including the USA, the EU, Canada and Australia) for use in adult patients on dabigatran when the reversal of its anticoagulant effects is required for emergency surgery/procedures or in the event of life-threatening or uncontrolled bleeding. In the ongoing pivotal RE-VERSE AD trial in these populations (n = 90), intravenous idarucizumab 5 g reversed dabigatran-induced prolongation of dilute thrombin time (dTT) and ecarin clotting time (ECT) within minutes. The median maximum percentage reversal was 100 % for both assays (primary endpoint). Idarucizumab normalized dTT and ECT in 88-98 % of patients who had elevated levels at baseline. After idarucizumab administration, bleeding stopped in 97 % of evaluable patients in the bleeding cohort within 24 h (median time to cessation of bleeding was 11.4 h), and the rate of normal intraoperative haemostasis was 92 % in the surgical cohort. Idarucizumab was generally well tolerated. In conclusion, idarucizumab is a unique and specific treatment option for the reversal of the anticoagulant effects of dabigatran in adult patients requiring emergency procedures or in the event of life-threatening or uncontrolled bleeding.

Using Direct Oral Anticoagulants in Patients with Atrial Fibrillation: Assessment, Monitoring and Treatment Reversal

It is essential to prevent thromboembolic events in atrial fibrillation. The risks of thromboembolic and haemorrhagic events must be carefully assessed and weighed against one another, both in routine situations and in relation to invasive procedures. Vitamin K antagonists, until recently the first-line treatment for prophylaxis against thromboembolic events in patients with atrial fibrillation, have various drawbacks. Direct-acting oral anticoagulants overcome these limitations and are efficacious and safe. The recent developments of tests to monitor anticoagulant levels, and of target-specific reversal agents for these newer drugs, has facilitated their use in several situations, including emergencies. For these reasons, the European Society of Cardiology and other scientific societies now recommend direct-acting oral anticoagulants as first-line treatment for preventing thromboembolic events in atrial fibrillation.