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What is a Stroke

A stroke is a serious condition that occurs when the blood supply is cut off to part of the brain. The blood carries oxygen and essential nutrients to the brain via the arteries, and if these become blocked, blood supply and therefore oxygen is restricted. As a result, brain cells become damaged and start to die.² This damage is called cerebral infarction, and the dead tissue is known as an infarct. Since the brain controls all of the body’s functions, brain damage from a stroke can affect any number of the stroke patient’s bodily functions, depending on whereabouts in the brain the damage occurs.¹ In addition to physical processes, the brain also controls mental processes, and so a stroke can lead to adverse effects on the way you think, learn, feel and communicate.¹ In the most severe cases, a stroke can result in death.³

There are three main types of brain strokes:

Ischaemic stroke: This occurs when arteries leading to the brain become blocked by blood clots, or narrowed due to plaque build up within the artery walls. Around 85% of all strokes are ischaemic.³ An ischaemic stroke can be caused by:

• A cerebral thrombosis, which is when a blood clot forms in one of the main carotid arteries leading to the brain
• A cerebral embolism, when a clot, air bubble, or fat globule forms in a blood vessel elsewhere in the body and is then carried to the brain via the bloodstream
• A lacunar stroke, which is when a blockage occurs in the tiny blood vessels deep within the brain tissue¹

Haemorrhagic stroke: This occurs when a blood vessel in the brain becomes weakened and bursts, leaking blood into the brain.^{2, 3} Although only about fifteen percent of all strokes are haemorrhagic they account for more than 30% of all stroke-related deaths.³ A haemorrhagic stroke can be caused by:

• An intracerebral haemorrhage, caused by a blood vessel bursting inside the brain
• A subarachnoid haemorrhage, which is when a blood vessel on the brain’s surface bleeds into the space between the brain and the skull¹

Transient ischaemic attack (TIA): Also called a ‘mini-stroke’, this is when the blood supply is temporarily interrupted to the brain, usually because a tiny blood vessel in the brain is blocked by a clot. Because the blockage is so small the affected part of the brain is only without oxygen for a short time, either because the blood clot breaks up quickly, or because blood vessels nearby are able to compensate. TIAs are often a warning sign that a more serious stroke is likely to happen in the future. You should seek urgent medical advice if you have a mini stroke.^{2, 6}

Disease Information

• Angina
• Depression
• Diabetes (Type 2)
• Heart Attacks
• Heart Failure
• High Blood Pressure
• Osteoporosis (Postmenopausal)
• Stroke