Stroke

What is a Stroke?

A stroke is an abrupt or sudden interruption affecting the arteries leading to and within the brain. When a stroke occurs, the blood supply to a part of the brain is either blocked by a clot or ruptures, which deprives the brain of oxygen and nutrients, and causes brain cells to die. Strokes are a type of cardiovascular disease.

What are the symptoms of a stroke?

There are many clues and symptoms of stroke to look out for. If the following signs occur, seek immediate medical health and note when the symptoms started:

• Trouble speaking and understanding or confusion
• Paralysis or numbness of the face, arm or leg
• Trouble with seeing in one or both eyes
• Headache which is sudden and severe, followed by vomiting and dizziness
• Trouble walking

What causes strokes?

High blood pressure (hypertension) is the most important known risk factor for stroke. High blood pressure can damage blood vessel walls and over time, this may lead to a stroke.

A stroke can occur in two main ways. It can either be caused by a blocked artery or the bursting of a blood vessel.

What are the different type of strokes?

There are three different types of strokes including:

Ischaemic Stroke

Approximately four out of five strokes are ischaemic. This occurs when the arteries to the brain become narrowed or blocked, severely reducing blood flow to the brain. The two common ischaemic strokes are:

• Thrombotic stroke which occurs when a blood clot forms in one of the arteries that supplies blood to the brain. A clot may form by fatty deposits or plaque, which builds up in the arteries, also known as atherosclerosis, and cause reduced blood flow.
• Embolic stroke which occurs when a blood clot forms outside of the brain and is then carried through the bloodstream and lodges in a narrower brain artery. These clots are commonly formed in the heart.

Haemorrhagic Stroke

Around one in every five strokes is haemorrhagic. A haemorrhagic stroke occurs when a blood vessel in the brain ruptures, causing blood to leak into the brain. The two common types of haemorrhagic stroke include:

• Intracerebral haemorrhage which can be caused by longstanding high blood pressure, trauma, vascular malformations or use of blood-thinning medications.
• Subarachnoid haemorrhage, commonly caused by an aneurysm, which is a weak or thin spot on a blood vessel wall.

Transient ischaemic attack

A transient ischaemic attack (TIA) or “mini stroke” has the same symptoms as a stroke but these disappear within 24 hours. The causes are similar to that of a stroke and a TIA should be regarded as a warning sign, as approximately one in five people who have a TIA will have a major stroke within the next three months.

How are strokes diagnosed?

To determine the possible type of stroke, and the area of the brain most affected, doctors may need to run the following diagnostic tests:

• Physical examination
• Blood tests
• CT scan
• MRI
• Carotid ultrasound
• Cerebral angiogram
• Echocardiogram

How is a stroke treated? What treatments are available?

Treatment will depend on the type of stroke experienced as differentiated below.

Ischaemic stroke treatment

To treat an ischaemic stroke, doctors need to restore blood flow to the brain quickly. Doctors may do this through:

• Medication e.g. aspirin, intravenous injection of tissue plasminogen activator
• Medications delivered directly to the brain
• Mechanical clot removal
• Carotid endarterectomy
• Angioplasty and stents

Haemorrhagic stroke treatment

Treatment of a haemorrhagic stroke focuses on controlling the bleeding and reducing pressure in the brain. Doctors may need to do the following:

• Surgical blood vessel repair
• Surgical clipping
• Coiling (endovascular embolization)
• Surgical AVM removal
• Intracranial bypass
• Stereotactic radiosurgery

Stroke recovery and rehabilitation

Every patient’s recovery differs and depends on the condition. Treatment may include:

• Seeing a neurologist (doctor trained in brain conditions)
• Seeing a rehabilitation doctor
• Nurse
• Dietician
• Physical therapist
• Occupational therapist
• Recreational therapist
• Speech therapist
• Social worker
• Case manager
• Psychologist

How can you prevent a stroke from happening?

A stroke can happen to anyone. Certain unchangeable factors like age, gender and family history can lead to an increased risk of stroke, however lifestyle modifications can prevent the likelihood of stroke from occurring. These include:

• Manage high blood pressure
• Manage high blood cholesterol
• Quit smoking
• Manage weight
• Eat a healthy diet
• Exercise regularly, starting with daily walking
• Drink alcohol in moderation