Long-term Anticoagulation Therapy in Prevention of Stroke

Long-term anticoagulation continues to be used and investigated as a means to prevent new or recurrent stroke. The best-established indications for long-term anticoagulation are cardiac abnormalities capable of producing intracardiac thrombi that may embolize into the brain or systemic circulation. The firmest cardiac indications are mechanical prosthetic heart valves, mitral stenosis with atrial fibrillation, and atrial fibrillation with additional features placing them at increased risk for stroke. These and other "major" cardiac potential sources of emboli should be considered as anticoagulation candidates unless the estimated risk of bleeding is prohibitive. A number of noncardiac potential causes of stroke are generally managed with long-term anticoagulation. These include arterial dissections, cerebral venous sinus thrombosis, the antiphospholipid antibody syndrome, and congenital and acquired coagulopathies. Recent randomized studies do not support the use of long-term anticoagulation for the prevention of recurrent stroke in patients with noncardioembolic stroke that is not due to the previously outlined disorders. Whether long-term anticoagulation is beneficial in the specific population of patients with major documented intracranial atherosclerotic stenosis is currently under investigation.