Stroke

A stroke, or cerebrovascular accident, occurs when blood flow to the brain is interrupted by the obstruction or rupture of an artery. This interruption prevents oxygen and nutrients from reaching the tissues and causes cell death, resulting in permanent brain damage.

There are two types of cerebrovascular accidents based on their origin:

• Hemorrhagic stroke (brain hemorrhage): The blood flow is stopped because a cerebral artery breaks and bleeding occurs. It can be of two types:
• Intracerebral hemorrhage: Blood flows inside the brain.
• Subarachnoid hemorrhage: It occurs in the space between the brain and the skull.
• Ischemic stroke (cerebral infarction): The most common form. Blood flow is stopped because an artery narrows or becomes blocked.
• Transient ischemic attack occurs when an artery is blocked but, after a short period, it is opened again, or a new blood flow pathway is created. It usually disappears without leaving sequelae.

A stroke is a medical emergency that can have fatal consequences for the body, being one of the leading causes of disability and mortality in adults.

Symptoms

The symptoms of a stroke depend on the affected area and usually appear suddenly and abruptly, though sometimes they may go unnoticed. The most common symptoms are:

• Severe and sudden headache without an apparent cause.
• Numbness (sensation alteration) or weakness in the face, arms, or legs, particularly on one side of the body.
• Confusion and difficulty speaking or understanding.
• Vision problems in one or both eyes.
• Dizziness and loss of balance or coordination.

Causes

Each type of stroke originates from a specific cause:

• Hemorrhagic stroke:
• High blood pressure.
• Excessive use of anticoagulants.
• Head trauma.
• Aneurysms.
• Weakness in arterial walls.
• Ischemic stroke:
• Progressive narrowing of the arteries due to the buildup of fat and cholesterol deposits on arterial walls.
• Blood clot in a cerebral artery (thrombotic stroke).
• Blood clot from another blood vessel in the body that detaches and moves to a cerebral artery (embolic stroke or cerebral embolism).
• Air bubble.
• Foreign substance.

Risk Factors

Several factors increase the likelihood of experiencing a stroke:

• Age: The risk increases after 55 years.
• Hypertension.
• High cholesterol.
• Diabetes.
• Family history.
• Personal history of transient ischemic attack or stroke.
• Cardiovascular diseases.
• Use of contraceptives or hormone therapies.
• Pregnancy and postpartum, due to increased blood pressure.
• Smoking.
• Overweight or obesity.
• Sedentary lifestyle.
• Alcoholism.
• Use of illicit stimulants.

Complications

The consequences of a stroke depend on the duration the brain goes without receiving oxygen and which part of the brain is affected. On one hand, the risk of a second stroke increases in the weeks following the first one. On the other hand, severe losses in motor, cognitive, and emotional capabilities can occur:

• Partial or total paralysis of muscles.
• Loss of memory and reasoning ability.
• Vision problems.
• Difficulty controlling emotions.
• Depression.
• Pain.
• Numbness.

In many cases, these sequelae may improve or even disappear over the following weeks or months. However, if treatment is not administered on time, they may be irreversible or lead to death.

Prevention

A stroke can be prevented by avoiding risk factors and promoting a healthy lifestyle:

• Avoid tobacco and drugs.
• Limit alcohol consumption.
• Follow a healthy, low-sodium and low-fat diet rich in vegetables and whole grains.
• Exercise regularly.
• Maintain a healthy weight.
• Control blood pressure and diabetes.

What doctor treats a stroke?

A stroke is assessed and treated by specialists in neurology and neurosurgery, also within cardiovascular risk units, emergency departments, and cardiovascular surgery.