A cerebrovascular accident (CVA) is caused by a problem with blood circulation to the brain, resulting in brain tissue suffering from a lack of oxygen and nutrients. 

There are two main causes of stroke, depending on the type:

 

1. Ischemic stroke (80-85% of cases)

Ischemic stroke occurs when the blood supply to part of the brain is blocked. This can be caused by :

- Thrombosis:

Formation of a blood clot (thrombus) in a narrowed cerebral artery, often due to atherosclerosis (deposition of fatty plaques on artery walls).

- Embolism:

A clot or fragment of fatty plaque, formed in another part of the body (often the heart or a large artery), migrates to the brain and obstructs an artery. This is common in people with atrial fibrillation or heart disease.

- Reduced overall blood flow:

A significant drop in blood flow can occur during severe hypotension (shock, cardiac arrest or dehydration).

 

2. Hemorrhagic stroke (15-20% of cases)

Hemorrhagic stroke is caused by a rupture of a blood vessel in the brain, resulting in cerebral hemorrhage. Causes include:

- Hypertension:

The main cause. High blood pressure weakens blood vessel walls, promoting rupture.

- Cerebral aneurysms:

Abnormal dilatations of a blood vessel that can rupture and cause hemorrhage.

- Vascular malformations (AVMs)

: congenital malformations of the cerebral vessels can lead to spontaneous rupture.

- Coagulation disorders or anticoagulant drugs:

These can increase the risk of hemorrhage if the vessels are fragile.

- Head trauma:

A head injury can cause cerebral hemorrhage.

 

Risk factors common to both types of stroke:

Certain conditions increase the risk of stroke, whatever the cause:

1. Hypertension (the main factor).

2. Smoking.

3. Diabetes.

4. High cholesterol and atherosclerosis.

5. Obesity and sedentary lifestyle.

6. Excessive consumption of alcohol or drugs (cocaine, amphetamines).

7. Cardiac disorders: atrial fibrillation, heart failure.

8. Family or personal history of stroke or cardiovascular disease.

 

The symptoms of a stroke appear suddenly and depend on the area of the brain affected:

Main signs:

1. Sudden paralysis or weakness on one side of the body

- Difficulty moving one or both arms or legs on the same side.

- Feeling of heaviness or total loss of muscle strength.

2. Numbness or loss of sensation

- A tingling sensation or numbness on one half of the face, arm or leg.

3. Facial deviation (facial asymmetry)

- One side of the face may appear sunken (e.g. drooping mouth or cheek).

4. Speech disorders

- Difficulty speaking clearly (dysarthria).

- Incoherent or incomprehensible speech.

- Sudden inability to find words or understand what is being said.

5. Vision disorders

- Sudden loss of vision in one or both eyes.

- Blurred, double vision or sudden decrease in visual field.

6. Vertigo and balance disorders

- Feeling of imbalance, inability to walk upright or dizziness.

- Sudden loss of coordination or unexplained falls.

7. Sudden intense headache

- Mainly in hemorrhagic strokes.

- Sometimes described as the “worst headache of one's life”, often accompanied by nausea, vomiting or stiff neck.

8. Mental confusion

- Difficulty understanding what is going on, or inability to follow a conversation.

 

Other important points:

- Symptoms can be transient (disappearing within minutes or hours), especially in the case of a transient ischemic attack (TIA), which is a warning sign of a more serious future stroke.

- Prompt treatment is crucial: the earlier treatment is started, the lower the risk of permanent after-effects.

 

In all cases: persistent or transient symptoms, or when in doubt, call 15, because a stroke is a VITAL EMERGENCY.

FAST treatment is essential to start therapy and limit brain damage.