Phase 2 Acute And Subacute Phase - Treating Ischemic Stroke: Stroke

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Phase 2: Acute and subacute phase

The acute and subacute phase therapy will begin after the thrombolytic treatment has ended, or if your doctors decide not to use thrombolytic treatment. Phase 2 therapy can last several days, until you receive a confirmed, precise clinical diagnosis and begin therapy to prevent another stroke.

During phase 2, MRI images of your brain may be taken to look for further damage from the stroke. If you did not seek medical help during the hyperacute phase, doctors will go directly to acute phase therapy and try to determine whether an artery is blocked and, if so, where and why. Intravenous antithrombotic, or anticoagulant, medication is often used during phase 2 therapy to prevent further clotting. If you've had an embolic stroke, you may also undergo echocardiography, heart monitoring, and various laboratory tests. These can help the doctor predict your risk of developing a blood clot in the heart.

Thrombolytic medication is not an option during phase 2 therapy because of the risk of hemorrhage. An area of the brain already damaged by a stroke can hemorrhage drastically beyond the area already affected by the clot.

Antithrombotic (anticoagulant) therapy

Antithrombotic drugs (also known as anticoagulants or blood thinners) help prevent the formation of blood clots. In the acute phase, doctors typically use heparin — delivered intravenously or by injection — for this purpose. Oral anticoagulant therapy, such as warfarin (Coumadin), may be used later, in the preventive phase.

Doctors consider using intravenous heparin when clot-dissolving (thrombolytic) therapy is not given or, in selected cases, immediately after intra-arterial thrombolysis in order to keep the blood vessel open. Intravenous heparin is most often used in treating stroke or TIA caused by a narrowing in a major artery, such as the carotid artery, the middle cerebral artery, the distal vertebral artery, or the basilar artery, where further clotting and embolization are likely to occur.

Doctors also consider using this drug to treat embolic stroke if thrombolytic therapy is not given, particularly when the embolic clot is thought to still be in the brain artery before it dissolves naturally. Because there hasn't been a large clinical study of heparin in which the precise cause of the stroke or TIA was documented, proof of its effectiveness is lacking. Therefore, doctors must evaluate each situation on a case-by-case basis. It may be useful when the cause of stroke or TIA is a clot blocking a major artery in the neck or at the base of the brain that could expand and cause more damage, although some physicians are not convinced that it helps.

Last updated:	September 05, 2008