Stroke

Patient Information Series

What is Stroke?

Stroke is due to sudden damage to a part of the brain leading to loss of function. The effects depend on which part and how much of the brain is involved and include paralysis of a part of the body and/or face, disturbance of speech, vision, balance, or swallowing and bowel/bladder incontinence. Severe cases may result in unconsciousness and death. Recovery may be partial or complete. When the effects are transient with full recovery within 24hours this is termed a Transient Ischaemic Attack (TIA) or mini-stroke.

What is the cause?

The two commonest causes are a sudden blockage to the blood supply to the brain by a clot (ischaemic stroke) and bleeding within the brain (haemorrhagic stroke). The clot usually arises from a diseased, furred carotid artery (from atherosclerosis) or the heart especially when its rhythm is irregular.

How is the diagnosis made?

The doctor would take a history and examine the patient. However a brain scan in the form of a CT or MRI scan is essential to confirm the diagnosis and differentiate between ischaemic and haemorrhagic stroke.

How is Stroke treated?

This should ideally be in a specialist stroke unit. Management is by a multi-disciplinary approach involving the doctor, nurse, physiotherapist, speech therapist, dietician, occupational therapist and social worker. Early rehabilitation is imperative to restore some degree of independence to the patient. Stroke clubs and the Stroke Association are invaluable for support and education.

What are the Risk Factors for Stroke?

These include:

Hypertension
Smoking
Diabetes
Obesity
High blood cholesterol
Excessive alcohol
High salt and fat diet
Lack of exercise

Prevention

Prevention is by controlling, modifying or avoiding the above risk factors.
Irregular heart rhythms (atrial fibrillation) may require anticoagulation with warfarin to prevent clot formation within the heart.
Low dose aspirin is beneficial in preventing a further stroke.
Patients with severe narrowing of the carotid artery(>70%), diagnosed by Doppler ultrasonography and/or angiography benefit from surgery (carotid endarterectomy). Balloon dilatation (angioplasty) is under trial.