A Brief Overview of Stroke

Stroke is a leading cause of disability in the United States. It occurs when blood flow to part of your brain is blocked by a clot or burst blood vessel. Your brain needs a continuous supply of oxygen and nutrients, so it’s important to get treatment as soon as possible.

What Is Stroke?

A stroke occurs when blood stops flowing to part of your brain after a clot forms or a blood vessel ruptures. This can result in lasting damage to your brain cells and loss of function in that part of your body. Stroke may cause paralysis, speech problems and difficulty thinking clearly.

What Causes a Stroke?

Stroke is caused by a blockage or rupture in an artery in the brain. A stroke occurs when blood flow to an area of the brain stops. This can be caused by a clot that blocks an artery, a burst blood vessel (hemorrhagic stroke), or bleeding into the brain (intracerebral hemorrhage).

Stroke symptoms vary depending on where the stroke occurs in the brain and how serious it is. Some people have no signs or symptoms at all, while others experience sudden weakness or paralysis, loss of consciousness and difficulty speaking or understanding speech.

Stroke can also result from a ruptured brain aneurysm. The symptoms of this type of stroke are similar to those for other types of strokes but may include headache or vomiting. In general, if you experience any sudden signs or symptoms that indicate stroke — such as weakness of your face, arm or leg; sudden confusion; vision problems; trouble speaking; or sudden severe headache with no known cause.

Warning Signs of a Stroke

Stroke warning signs include:

• Sudden numbness or weakness of face, arm or leg on one side of the body
• Sudden confusion, trouble speaking or understanding
• Sudden trouble seeing in one or both eyes
• Sudden trouble walking, dizziness, loss of balance or coordination
• Sudden severe headache with no known cause

Leading Causes of Stroke

High blood pressure. High blood pressure increases your risk for stroke. When you have high blood pressure, your heart has to work harder to pump blood around the body. In some cases, the force of the blood can cause the walls of an artery to stretch and bulge. This is called an aneurysm. If the wall breaks or leaks, a clot may form in that spot. The clot can block blood flow through the artery and cause a stroke.

Atrial fibrillation (irregular heartbeat). Atrial fibrillation is a common heart condition that affects about 2 percent of people 65 years and older. It causes an irregular heartbeat that can lead to blood clots forming in an abnormal place in the heart’s upper chambers (atria). Blood clots then break off and travel into other parts of your body — most often, your brain. This causes a stroke.

Heart disease. Heart disease is another leading cause of stroke because it can increase your risk for having abnormal heart rhythms (arrhythmias), particularly atrial fibrillation, which can lead to blood clots forming in an abnormal place in the heart’s upper chambers (atria).

1. Hypertension (High Blood Pressure)

Hypertension (high blood pressure) is an important risk factor for stroke.

Stroke is the third leading cause of death in the United States, and the leading cause of disability among adults. Each year, more than 795,000 Americans have a new or recurrent stroke and about 140,000 die from it.

High blood pressure is a major risk factor for heart disease and stroke. It’s estimated that one out of every three American adults has high blood pressure, but only half of them know it. High blood pressure increases the risk for heart disease, heart failure and kidney disease.

The good news is that high blood pressure can be controlled through lifestyle changes and medication if necessary.

2. High Cholesterol

High cholesterol is a risk factor for heart disease, which can lead to heart attack and stroke.

High cholesterol can lead to plaque buildup in your arteries, which narrows the passageways for blood. When this happens, it’s harder for your heart to pump blood through your body. This can cause chest pain (angina) or a heart attack if the blockage becomes severe enough.

If a blood clot forms because of plaque buildup in an artery leading to your brain (the carotid artery), it can travel through the bloodstream and lodge in an artery in your brain. This is known as an embolism, or cerebral embolism. A cerebral embolism, also known as a stroke or cerebrovascular accident (CVA), occurs when an artery carrying oxygen-rich blood to the brain becomes blocked by a clot or ruptures.

3. Diabetes

Diabetes is the leading cause of stroke and a major risk factor for heart disease. The American Heart Association recommends screening for diabetes at least once every three years in people who are ages 45 or older and at least once every two years in people who have other cardiovascular risk factors, such as high blood pressure, high cholesterol levels and being overweight.

Diabetes occurs when your body can’t properly produce or use insulin, which can lead to high blood sugar levels over time. High blood sugar levels can damage your blood vessels, including those in your brain. When the lining of these blood vessels breaks down, it’s called a stroke.

The risk of having a stroke increases with age, but it also increases if you have diabetes. If you have diabetes and don’t take care of yourself (by controlling your blood sugar levels), you may be more likely to have a stroke than someone without diabetes.

4. Obesity

Obesity increases the risk of stroke in several ways. It can lead to high blood pressure, high cholesterol levels, diabetes and heart disease — all risk factors for stroke.

Obese people also tend to have more fat around their waist than normal-weight people do. This extra fat puts more stress on the blood vessels supplying the heart, increasing the risk of developing coronary artery disease (CAD). As CAD progresses it can cause narrowing of the arteries that bring blood to your heart muscle and decrease your ability to exercise. This may make you feel tired more easily and reduce your ability to perform simple daily tasks like climbing stairs or carrying groceries up a flight of stairs.

5. Smoking

Smoking is the leading cause of stroke, accounting for about 27 percent of strokes. Stroke is a medical emergency and can lead to permanent brain damage.

A stroke occurs when blood flow to part of the brain stops. This causes brain cells to die from lack of oxygen (infarction) or from bleeding (hemorrhage). A stroke can occur in one area or several areas of the brain at the same time.

Smoking increases your risk for stroke by causing heart disease and increasing your blood pressure. Smoking also makes it more difficult for your heart to pump blood around your body. If you have high blood pressure and smoke, this combination puts you at even higher risk for a stroke.

Smoking also increases your risk for having a heart attack, which can cause you to have a stroke while you’re recovering from surgery or during an operation.

Management Tips for the Leading Causes of Stroke

Get treatment for high blood pressure. If you have high blood pressure, it’s important to take your medications as prescribed by your doctor and follow up with your doctor regularly. High blood pressure can lead to other health problems, such as heart disease, kidney disease and heart failure.

Stop smoking if you smoke cigarettes. Smoking damages the lining of blood vessels and increases your risk for stroke and heart attacks by 50 percent compared with nonsmokers’ risks. Quitting smoking lowers this risk significantly — within 20 years after quitting smoking, a person’s risk of dying from smoking-related diseases is the same as that of someone who has never smoked. Talk to your doctor about strategies to help you quit smoking.

What are the treatment for Stroke

Stroke treatment is designed to restore blood flow to the brain, which can help prevent permanent damage. Stroke treatment may include medication, surgery and rehabilitation.

Treatment times depend on how severe your stroke was and what parts of your brain were affected.

Medications

The first step in treating stroke is giving you medicine to dissolve blood clots. You might receive medications called thrombolytics (alteplase, reteplase) or antiplatelet drugs (aspirin). These drugs must be given within hours of the stroke to be effective.

These medicines can cause bleeding inside the brain — a risk that increases with age. They are not approved for use in people older than 80 years old or those who have certain medical conditions such as kidney failure, uncontrolled high blood pressure or heart disease.

Surgery

If you have an aneurysm (an abnormal bulge in an artery wall), surgery may be necessary to repair it before more damage occurs from bleeding into the brain. This procedure is called clipping or coiling (inserting coils into the artery).

Types of Stroke

Ischemic stroke. This is the most common type of stroke, accounting for about 87% of strokes. Ischemic stroke occurs when a clot blocks an artery in the brain, reducing or cutting off blood flow to the brain. This deprives brain cells of oxygen-rich blood they need to survive. Blood clots that form in the body, such as those found in atrial fibrillation (a type of irregular heart rhythm), can break loose and travel through arteries to reach the brain. Blood clots may also be caused by underlying medical conditions such as atrial fibrillation, heart valve disease, hypertension (high blood pressure), or diabetes mellitus (diabetes).

Hemorrhagic stroke. Hemorrhagic strokes account for about 13% of all strokes, according to the National Stroke Association (NSA). A hemorrhagic stroke occurs when a weakened vessel in your brain bursts open, leaking blood into surrounding tissue. Bleeding from this type of stroke may cause immediate symptoms such as swelling or bleeding within your brain tissue and/or on its surface (lacunar infarction).

Stroke Clinical Trials

Stroke clinical trials are research studies that look at new ways to prevent, find and treat stroke. Clinical trials are one way we learn about treatments and new ways to prevent diseases like stroke. In clinical trials, treatments being studied in patients may be new drugs, vaccines, or other therapies.