What is a Stroke?

Stroke is a syndrome caused by a disruption in blood flow to a part of the brain. It occurs when the blood vessel either ruptures or becomes blocked. A stroke deprives the neurons and other brain cells of glucose and oxygen, which leads to cell death. The longer the brain is deprived of oxygen and nutrients, the higher the likelihood of permanent damage to the brain.

Types of Stroke

Broadly, there are two types of strokes: ischemic (85% of all strokes) and hemorrhagic (15% of all strokes).

Ischemic Stroke

An ischemic stroke is caused by interruption in blood flow due to sudden blockage of a brain artery.

Hemorrhagic Stroke

A hemorrhagic stroke is caused by rupture of a brain artery leading to bleeding into the brain or into the spaces around the brain.

Interruption of normal blood flow prevents the brain from receiving adequate nutrients (e.g., glucose and oxygen) necessary for survival. Bleeding into the brain causes compression and damage from swelling.

Stroke results in permanent death of one region of the brain – it is a form of permanent brain damage. The effects of a stroke depend on the location and severity of damage. Most commonly, a stroke is associated with weakness on one side of body, difficulty with speech or understanding speech and loss of vision. Stroke can also result in cognitive difficulty (e.g., problems with speech, memory and concentration), loss of sensation or imbalance.

A trans ischemic attack is the mildest form of ischemic stroke. It is a short-lived stroke lasting typically less than 30 minutes. A transient ischemic attack is often a warning sign for a future major ischemic stroke.

A stroke can be a life-altering event, or a fatal event. In Canada, approximately one in six patients with stroke will die in the first 30 days. Stroke survivors may face great limitation in ability, necessitating alternate methods and assistance for carrying out everyday activities. It is common for older adults who have suffered stroke to require long-term care. However, almost every stroke survivor can recover some function. Treatments for acute ischemic stroke vary, but include: clot-busting drugs or advanced endovascular treatment in appropriately selected patients. In order to improve functional recovery, patients may be offered physiotherapy, occupational therapy, speech-language therapy and adjusted living (in the case of paralysis).

The best treatment for stroke is prevention.

The likelihood of having a stroke can be greatly reduced by controlling blood pressure. Other modifiable risk factors for stroke include smoking, high alcohol intake, poor diet, high cholesterol and substance abuse. It is important to concurrently maximize physical activity, healthy diet and good sleeping habits.