Review Article Haematologic Disorders and Cerebral Venous Thrombosis

This review focuses on the several coagulation disorders (the so called hypercoagulable states) that are associated with cerebral venous thrombosis. Hypercoagulable states likely explain the high percentage of cases of cryptogenic cerebral infarction in young people. The most common of the hereditary defects appear to be deficiency of antithrombin III, protein C or protein S, activated protein C resistance and prothrombin 20211A mutation. In a large majority of cases activated protein C resistance is due to the presence of factor V Leiden. Antiphospholipid antibodies (lupus anticoagulant and anticardiolipin antibodies) represent an acquired disorder of coagulation. Rare defects include heparin cofactor II (HC II), plasminogen or tissue plasminogen activator deficiency (TPA), elevated plasminogen activator inhibitor-1 (PAI-1) and dysfibrinogenemia. Hyperhomocystinemia is responsible for both arterial and venous thrombosis. A work-up to identify one of the recognizable hypercoagulable states is indicated, especially in younger patients with stroke. Laboratory evaluation for hypercoagulable states may also often be indicated in those patients who do not have other obvious risk factors for their stroke. If from clinical history, family history and/or laboratory studies, a patient is felt to have a hypercoagulable state, the decision for long term chronic anticoagulation needs to be individualized. If a hereditary hypercoagulable state is found, it also may be appropriate to recommend screening of other family members.