Causes of a Stroke

Causes of a Stroke or mini stroke are innumerable in number as enlisted below.

1) Arterial strokes (caused by damage or blockage to the artery supplying the brain)

2) Venous Strokes (due to blockage, or damage to the veins or dural venous sinuses of the brain etc)

1) Arterial strokes:

A) Thrombosis related:

a) Thickening of the wall of the artery due to a process called atherosclerosis;

• Chronic high blood pressure (hypertension or HTN)
• Diabetes mellitus
• High triglycerides
• High cholesterol (the bad cholesterol e.g. LDL) etc

b) Trauma to the artery (e.g. Carotid artery dissection, vertebral artery dissection etc)

c) Inflammatory or infectious process resulting in thrombosis & narrowing of arteries- vasculitis process e.g. lupus, herpes zoster, neurosyphilis, lyme, fungal, TB (tuberculous) arteriris related.

d) Toxin related e.g. hyper homocytinemia etc

B) Embolism related:

a) Originating from the heart (due to valvular damage, muscle wall damage, cardiac arrhythmias related etc)

b) Originating from another artery (ascending aorta, arch of aorta, carotid arteries, vertebral, basilar cerebral branches of these arteries)

c) Paradoxical embolism: Clot arising from the veins usually DVT (deep venous thrombosis of the legs) that reaches the brain circulation through a hole in the heart (e.g. patent formen ovale)

Venous Strokes:

Hypercoagulable states (these states can cause either arterial or venous strokes);

• Hormonal - estrogen excess (e.g. birth pills)
• Protein C or S deficiency
• Antithrombin iii deficiency
• Factor V Leiden mutation
• Antiphospholipid syndromes (lupus anticoagulant, anticardiolipin antiobodies)

Many of the above actors can result in a hemorrhagic or bleeding stroke (e.g. HTN, vasculiis etc) too. In addition to the above there are some specific conditions

• Rupture of berry aneurysm (saccuar aneurysm)
• AVM (arteriovenous malformations)
• Cavernous hemangioma
• Venous angioma
• Bleeding disorders

- Clotting factor deficiencies
- Platelet dysfunction
- Anticoagulant usage (e.g. warfarin)

Some Other causes of a stroke include;

• Sickle cell anemia
• Fibromuscular dysplasia
• Moyamoya disease etc

A neurologist is frequently involved in the care of stroke & mini stroke patients.