Stroke

What is a stroke?

A stroke is a life-threatening, medical emergency that happens when there is a loss of blood flow to part of the brain. When a stroke occurs, it causes a portion of your brain cells to die.

There are two types of strokes: ischemic stroke and hemorrhagic stroke. Ischemic strokes are the most common and are caused by a blood clot in the brain. When the blood flow is blocked, your brain does not get enough oxygen. With a hemorrhagic stroke, a blood vessel breaks in the brain causing bleeding and increased pressure within the brain.

Some hemorrhagic strokes are caused by a cerebral aneurysm or weakened blood vessel in the brain that bursts. Others are caused by an arteriovenous malformation (AVM). The blood vessels in an AVM are weak and not normal, causing blood to flow away from healthy brain tissue.

The brain damage from a stroke can be temporary or permanent. The sooner that you receive treatment after a stroke, the better the chance of returning blood flow to your brain and reducing damage.

Symptoms of a stroke

The signs and symptoms of a stroke can depend on the type of stroke and part of the brain affected. They can occur quickly or develop over hours, even days. Symptoms may include any of the following:

• Sudden weakness or numbness of the face, arm or leg on one side of your body
• Sudden trouble seeing in one or both eyes
• Trouble talking or understanding what others are saying
• Sudden severe headache with no known cause
• Sudden unexplained dizziness
• Falling or unstable walking

The B.E. F.A.S.T. test is a quick and easy way to determine if someone is having a stroke.

B – Balance: Ask the person to walk in a straight line. Is there a loss of balance or coordination? Is the person dizzy or having trouble walking?

E – Eye (Vision) Changes: Ask the person if they have blurred vision, double vision or loss of vision in one or both eyes.

F – Face: Ask the person to smile. Does one side of the face droop?

A – Arms: Ask the person to raise both arms. Does one arm drift downward?

S – Speech: Ask the person to repeat a simple phrase. Is their speech slurred or strange?

T – Time: If you observe any of these signs, call 9-1-1 right away. Early treatment is critical.

Another condition that is similar to a stroke is called a transient ischemic attack (TIA). A TIA is a "mini stroke" that can have symptoms similar to those listed above. Symptoms may only last a few minutes up to an hour, but a TIA increases your risk of having a stroke later. If you are diagnosed with a TIA in an emergency room, it is important to schedule immediate follow-up with your doctor to manage and discuss ongoing symptoms and risk factors.

How is a stroke diagnosed?

Immediate medical care is critical if experiencing signs and symptoms of a stroke. Your doctor will diagnose a stroke based on your health history, physical exam and diagnostic tests. These tests may include:

Computed tomography (CT) brain scan. A CT scan is similar to an x-ray. Detailed pictures from the scan of your brain can tell your doctor if you have had a stroke from a bleed. This test is often done right after a suspected stroke.

Magnetic resonance imaging (MRI). A MRI uses magnets and radio waves to create pictures of your brain. This test can be used instead of, or in addition to, a CT scan.

Blood tests will give your doctor information about how quickly your blood is clotting and your blood glucose (sugar) levels. Controlling how quickly your blood clots and your blood glucose level is necessary to prevent further damage. These tests also help determine if certain medications can treat your stroke. 

Additional imaging tests may help your doctor determine the best treatment plan:

Cerebral angiogram. This test inserts a thin, flexible tube through an artery in your groin. The tube travels through your major arteries and into your carotid artery to get a clear view of the arteries in your neck and brain.

Carotid ultrasound. This test uses sound waves to create pictures of the inside of the carotid arteries in your neck to see how well your blood is flowing.

How is a stroke treated?

Treatment depends on whether you had an ischemic or hemorrhagic stroke, how much time has passed since symptoms started and whether you have other medical conditions. Immediate treatment options include the use of blood-thinning (clot buster) medicine, surgery or other procedures. Treatment depends on the type of stroke.

Ischemic stroke treatment

The main treatment for an ischemic stroke is a medicine called tissue plasminogen activator (tPA). It breaks up the blood clots that block blood flow to your brain.  It must be given within three hours after stroke symptoms have started.

A thrombectomy may be performed to remove the clot from the blood vessel and return blood flow to the brain. A surgeon will use a thin tube to insert a balloon into the artery (angioplasty) or a small mesh tube (stenting) that makes space for blood to flow to the brain.

Hemorrhagic stroke treatment

When a blood vessel in the brain has ruptured or burst, known as an aneurysm, a doctor may perform various procedures or surgery. Clips, like tiny clamps, can be placed at the location of the aneurysm in the brain to stop and prevent further bleeding. This is known as aneurysm clipping.

Coil embolization is a procedure where a coil is pushed through a flexible tube in the artery and into the aneurysm. This coil causes a blood clot to form and prevent further bleeding.

Life after a stroke

After experiencing a stroke, you may have temporary or lifelong side effects. The following are the most common side effects of a stroke:

• Weakness or paralysis on one side of the body
• Problems with speech and language
• Poor balance or clumsy movement
• Trouble swallowing
• Problems with bladder or bowel control
• Problems with speaking, thinking or memory
• Loss of vision or hearing
• Numbness

In addition to the physical changes, brain injury and loss of function after a stroke can lead to mood and behavior changes, as well as trouble controlling your emotions. It can take weeks, months or even years to recover from a stroke. Stroke rehabilitation and regular follow-up with your doctor are important parts of the recovery process. Rehabilitation helps build strength, coordination and endurance. It also helps you learn how to live independently with the side effects of a stroke. It may include physical therapy, occupational therapy and speech therapy.

Your health care team will develop a treatment plan to address your physical and mental needs. Your doctor will also help you take important steps to help prevent a stroke in the future. Your follow-up care may also include a team of specialists, such as a neurologist or vascular surgeon, depending on the type and cause of your stroke.

Risk factors and stroke prevention

Many stroke risk factors can be treated or controlled. These include:

• Smoking
• Being overweight
• Being inactive
• High cholesterol
• High blood pressure
• Diabetes

Some risk factors are specific to the type of stroke. Blood clots can come from:

• Coronary heart disease (plaque buildup in heart vessels)
• Atrial fibrillation (irregular heartbeat)
• Heart valve disease
• Carotid artery disease (plaque buildup in blood vessels of the neck)

Your age, family history, race and ethnicity or unhealthy lifestyle habits can also increase your risk of a stroke. Your family doctor can help you manage the conditions that increase your risk and provide guidance on making lifestyle changes to reduce the risk of a stroke.