Adult “idiopathic” extrahepatic venous thrombosis

The etiology of extrahepatic venous obstruction (EHVO) is unknown in 50% of cases. Recently the presence of a latent myeloproliferative disorder has been reported in adults with idiopathic EHVO. We evaluated the course of these patients to establish if any putative latent myeloproliferative disorder influenced the clinical course compared to those with a known cause. Among 132 EHVO patients, 78 (59%) had a known etiology, 7 (5%) with an overt myeloproliferative disorder. The idiopathic group had 54 patients; 24 (13 men, 11 women) were diagnosed after 15 years of age, (median 38 years, range 17–70) with a median follow up of 96 months (19–372). Only 2 (8%) developed an overt myeloproliferative disorder. These 24 had a similar pattern of bleeding and onset of ascites as those with known cause. In EHVO failure to diagnose a latent myeloproliferative disorder does not influence the course of variceal bleeding, and thus has little prognostic significance.Supported by R Farini Foundation for Gastroenterology Research.     

Does the location of thrombosis determine the risk of disease recurrence in patients with proximal deep vein thrombosis?

PURPOSE: To determine if the location of deep vein thrombosis is a predictor of recurrent venous thromboembolism during the initial 3 months of anticoagulant therapy.METHODS: The study population consisted of 1,149 consecutive patients with symptomatic proximal deep vein thrombosis. In all patients, deep vein thrombosis was confirmed by Duplex ultrasound or venography and was classified as popliteal, femoral, or iliofemoral. Patients received initial treatment with unfractionated heparin, enoxaparin, or reviparin for least 4 days, as well as a coumarin derivative, with a target international normalized ratio of 2.0 to 3.0, starting on the 1st or 2nd day of treatment. All patients were followed for 3 months, and all episodes of recurrent venous thromboembolism were confirmed with objective diagnostic tests.RESULTS: The overall rate of recurrent venous thromboembolism during the initial 3 months of anticoagulant therapy was 5.5% (63/1,149). The rate of recurrence in patients with popliteal vein thrombosis was 5.1% (23/453); in patients with femoral vein thrombosis, it was 5.3% (34/645); and in patients with iliofemoral vein thrombosis, it was 11.8% (6/51). Two clinical risk factors were associated with an increased risk of recurrent venous thromboembolism: iliofemoral vein thrombosis (odds ratio [OR] = 2.4; 95% confidence interval [CI]: 0.95, 5.9), and cancer (OR = 2.6; 95% CI: 1.5, 4.4).CONCLUSIONS: Patients with extensive iliofemoral vein thrombosis who receive conventional anticoagulant therapy have a greater than twofold higher risk of developing recurrent venous thromboembolism than patients without iliac vein involvement (i.e., 11.8% vs. 5.2%). Prospective studies are needed to determine whether alternative antithrombotic strategies are warranted in such patients.     

Portal vein thrombosis: What is new?

Portal vein thrombosis (PVT) is one of the most common vascular disorders of the liver with significant morbidity and mortality. Large cohort studies have reported a global prevalence of 1%, but in some risk groups it can be up to 26%. Causes of PVT are cirrhosis, hepatobiliary malignancy, abdominal infectious or inflammatory diseases, and myeloproliferative disorders. Most patients with PVT have a general risk factor. The natural history of PVT results in portal hypertension leading to splenomegaly and the formation of portosystemic collateral blood vessels and esophageal, gastric, duodenal, and jejunal varices. Diagnosis of PVT is made by imaging, mainly Doppler ultrasonography. According to its time of development, localization, pathophysiology, and evolution, PVT should be classified in every patient. Some clinical features such as cirrhosis, hepatocellular carcinoma, and hepatic transplantation are areas of special interest and are discussed in this review. The goal of treatment of acute PVT is to reconstruct the blocked veins. Endoscopic variceal ligation is safe and highly effective in patients with variceal bleeding caused by chronic PVT. In conclusion, PVT is the most common cause of vascular disease of the liver and its prevalence has being increasing, especially among patients with an underlying liver disease. All patients should be investigated for thrombophilic conditions, and in those with cirrhosis, anticoagulation prophylaxis should be considered.     

Homocysteine and thrombosis: guilt by association?

The long-recognized connection between homocysteine and thrombosis is examined in this issue of Blood in a study conducted by Dayal and colleagues. The results challenge the proposed mechanisms by which disordered homocysteine metabolism triggers vascular disease.     

Ovarian vein thrombosis in Beh?et disease

We describe a 35-year-old Chinese woman with Beh?et disease complicated by recurrent gastrointestinal flares. During admission for acute lower abdominal pain, a computed tomographic scan of the abdomen showed thrombosis of the left ovarian vein. She was treated with increased immunosuppressant and oral anticoagulant. Although she was not compliant to oral anticoagulant with her international normalized ratio frequently subtherapeutic, her symptoms abated and the thrombosis resolved. There has been only 1 reported case of a patient with Beh?et disease presenting with postpartum ovarian vein thrombosis and pulmonary embolism and no reported case of Beh?et disease with ovarian vein thrombosis occurring outside pregnancy and the puerperium. Ovarian vein thrombosis is a rare cause of abdominal pain that should be considered in patients with Beh?et disease.     

Have we solved the problem of late thrombosis?

Late thrombosis (angiographic total occlusion associated with an acute coronary syndrome) is potentially a life-threatening complication after intracoronary radiation therapy. This review is intended to explore the pre-clinical and clinical evidence for late thrombosis, discuss the etiology, and provide guidelines for future management. Although we have gained a greater understanding of this complex entity, further research is required to curtail late thrombosis rates.     

Cytomegalovirus infection and thrombosis: a causative association?

Venous thrombosis is a well-organised complication of hospitalisation and has often been reported in the context of HIV infection. Less frequently cytomegalovirus (CMV) has been implicated in the development of thrombosis, although usually in the context of immunosuppression. We report the case of a young, immunocompetent individual who developed pulmonary emboli as a complication of CMV infection and describe the three proposed mechanisms by which this is thought to occur. The probable mechanism in our patient is discussed.     

Cardiac thrombosis as a manifestation of Behçet syndrome

Herein, we report 3 cases of Behçet syndrome that were accompanied by intracardiac thrombus. The 1st patient was a 30-year-old man who presented with dyspnea; a right atrial thrombus was identified upon transthoracic echocardiography. The 2nd patient was a 52-year-old man who was admitted for dyspnea; transthoracic echocardiography revealed an echogenic mass in the right ventricle. The 3rd patient was a 23-year-old man who was hospitalized for hemoptysis; the diagnosis of pulmonary embolism was made, and right ventricular thrombosis was found.Because these patients had no hemodynamic compromise, medical management consisting of immunosuppressive and anticoagulative therapy was adopted. This treatment resulted in complete dissolution of the thrombi.Key words: Anti-inflammatory agents, anticoagulants, Behçet syndrome/complications/drug therapy, colchicine/therapeutic use, cyclophosphamide/therapeutic use, embolism, pulmonary, pulmonary artery, thrombosis/drug therapy/epidemiology/etiologyBehçet syndrome is a multisystemic, chronic, inflammatory disorder of unknown cause. It is characterized by recurrent buccal aphthosis, genital ulcers, and uveitis with hypopyon. The mean age at which it occurs is 20 to 30 years; men are 2 to 5 times more often affected than women.¹Additional manifestations in other locations (skin, joints, gastrointestinal tract, genitourinary tract, central nervous system, cardiovascular system, and lungs) can appear and can influence the clinical course and prognosis. Although cardiac involvement during Behçet syndrome is uncommon and intracardiac thrombosis is exceptional, we report here 3 illustrative cases collected at our institution in Rabat, Morocco.     

F9 Malm?, factor IX and deep vein thrombosis

Background

We recently reported the association between the Malmö sequence variant in F9 (rs6048) and deep vein thrombosis.

Design and Methods

We aimed to study whether the association between F9 Malmö and deep vein thrombosis is explained by linkage disequilibrium with nearby single-nucleotide polymorphisms, and whether the association is explained biologically by F9 Malmö affecting factor IX antigen levels or activation of factor IX. We investigated the association of F9 Malmö and 28 nearby single-nucleotide polymorphisms with deep vein thrombosis in men from two case-control studies, LETS (n=380) and MEGA (n=1,469). We assessed the association of F9 Malmö with factor IX antigen level in male control subjects from LETS (n=191) and two subsets of MEGA (n=823 and n=484) and the association with endogenous thrombin potential in LETS control men. We studied the association between F9 Malmö and factor IX activation peptide in 1,199 healthy middle-aged men from the NPHS-II cohort.

Results

In the combined LETS and MEGA studies, the odds ratio (95% confidence interval) for the G allele of F9 Malmö, compared with the A allele, was 0.80 (0.69–0.93). One single-nucleotide polymorphism in F9, rs422187, was strongly linked to F9 Malmö (r²=0.94) and was similarly associated with deep vein thrombosis. No other single-nucleotide polymorphism or haplotype tested was more strongly associated. Factor IX antigen level, factor IX activation peptide levels and endogenous thrombin potential did not differ between F9 Malmö genotypes.

Conclusions

The F9 Malmö sequence variant was the most strongly associated with deep vein thrombosis among common single-nucleotide polymorphisms in the region. However, the biological mechanism by which F9 Malmö affects risk remains unknown.