What is a stroke?

A stroke, also called a cerebrovascular accident (CVA) or brain attack, occurs when an area of the brain is damaged following interruption to its blood supply. This results in deterioration of the mental and physical functions controlled by that particular area of the brain.

What is the cause?

There are three main causes:

• thrombosis: a clot forming in the artery to the area

• embolus: a small clot from elsewhere blocking the artery

• haemorrhage: bleeding into the brain (unlike the others, where the artery is blocked). The risk factors for stroke are:

• high blood pressure

• high cholesterol

• diabetes

• smoking

• heart disease

• abnormal rhythms of the heart such as atrial fibrillation (AF)

What are the symptoms?

The symptoms depend on the area of the brain affected and the cause. A haemorrhage usually has a sudden onset and a less favourable outlook. Sometimes a stroke is mild and the effects pass off in a day or so.

Symptoms include:

• unconsciousness

• confusion

• loss of power of speech

• loss of movement of part of the body (e.g. on one side of the body)

• double or blurred vision

• difficulty understanding questions

• headache

• dizziness

• difficulty walking or using arms

• numbness or a weak feeling on one side of the body (face, arm or leg).

How can strokes be prevented?

The risk factors need to be checked, especially high blood pressure and cholesterol, which must be kept under control. Other things to do are avoid smoking, avoid excessive alcohol intake, eat a low-fat healthy diet, keep to an ideal weight and have regular exercise. If you have been found to have hardening of the arteries to the brain, you may be advised to have tablets to prevent blood clots (thrombosis) forming. Aspirin can do this, and only a small dose is needed. Special blood-thinning tablets called anticoagulants (commonly warfarin) may also be prescribed by your physician to help prevent clots.

Reference

Murtagh's Patient education. 6th Edition