What Is a Stroke?
A stroke occurs when there is low oxygen or low blood flow to an area of the brain, which may result from a blood clot causing a blockage of blood flow (ischemic stroke), a leak in a blood vessel, or a burst blood vessel (hemorrhagic stroke). Blood carries oxygen to the brain, and when blood flow is diminished, part of the brain can become permanently damaged.
What Are Symptoms of Stroke?
Stroke patients who arrive at the emergency room within three hours of the onset of the first symptoms tend to be healthier three months after stroke than those who received delayed care.
Symptoms of stroke are usually sudden and may include:
- Numbness, weakness, or paralysis, especially on one side of the body or only an upper or lower extremity on one side
- Facial droop or facial numbness
- Confusion, difficulty speaking or inability to get words out, or difficulty understanding speech
- Vision problems in one or both eyes
- Problems walking, dizziness, loss of balance or coordination
- Severe headache
The American Heart Association and the American Stroke Association suggest you know the signs of a stroke and remember to act F.A.S.T.:
- Face Drooping: Does one side of the face droop or is it numb? Ask the person to smile.
- Arm Weakness: Is one arm weak or numb? Ask the person to raise both arms. Does one arm drift downward? Weakness or numbness usually appears on one side of the body.
- Speech: Is speech slurred, are they unable to speak, or are they hard to understand? Ask the person to repeat a simple sentence such as, "The sky is blue." Is the sentence repeated correctly?
- Time to call 911: If the person shows any of these symptoms, even if the symptoms go away, call 9-1-1 and get them to the hospital immediately.
What Causes Stroke?
The most common cause of stroke is a blocked artery in the brain due to a blood clot (thrombosis).
Risk factors for stroke include:
How Is Stroke Diagnosed?
A doctor will perform a physical exam and a detailed neurological exam and ask about your medical history and when stroke symptoms started. The time of onset of the stroke, exactly when it started if known, will help determine treatments.
Tests used to diagnose stroke include:
- Blood tests
- Complete blood count (CBC)
- Platelet count
- Glucose (sugar) levels
- Blood clotting tests
- Computerized tomography (CT) scan
- Magnetic resonance imaging (MRI)
- Cerebral angiogram
- Brain perfusion scan
- Electroencephalogram (EEG)
- Electrocardiogram (EKG)
- Evoked Response test
- Blood flow testing
- B-mode imaging
- Doppler testing
- Duplex scanning
- Lumbar puncture (spinal tap)
What Is the Treatment for Stroke?
The most common treatment for acute stroke is use of blood thinners. Alteplase (Activase), also referred to as tPA (tissue plasminogen activator) is a “clotbuster” drug used in emergency settings.
There are also invasive treatments which commonly include removing the clot from the blood vessel, which is done through an artery (endovascular treatments). These treatments consist of small catheters threaded through the arteries into the brain in the area of the clot. The clot is removed by suction or clot “retrievers.” These treatments are performed by highly trained neuro-interventionalist physicians in hospitals that are stroke centers.
Blood thinners are also used to prevent or decrease the risk of stroke in conditions such as heart disease, atrial fibrillation, heart valve disorders, hypercoagulable states, and previous cerebral vascular disease.
Neuroprotective agents are a new type of intervention being investigated that may help protect against potential stroke in certain patients. Neuroprotective drugs may help preserve brain structure and function. To date there are no approved neuroprotective medications, however, a number of different types of medications are under investigation and in clinical trials such as:
- Free-radical scavengers and antioxidants
- NMDA-receptor antagonists
- Inflammatory cascade inhibitors
- Different ion channel blockers/modulators
What Are Complications of Stroke?
Complications of stroke include:
- Blood clots
- Loss of muscle movement or control in one part of the body
- Pain, numbness, tingling or other strange sensations
- Muscle spasms
- Problems talking/understanding speech
- Difficulty reading and writing
- Difficulty swallowing
- Memory loss
- Cognitive problems such as difficulty thinking, reasoning, and understanding
- Inability to care for oneself
- Cerebral edema (brain swelling)
- Bladder/incontinence problems
- Chronic/severe headaches
How Do You Prevent Stroke?
Stroke may be prevented in some cases by healthy lifestyle modifications, such as:
- Eating a healthy diet, high in fiber and low in fat (plant-based diets may provide additional benefit)
- Maintaining a healthy weight/lose weight if you are overweight or obese
- Exercising regularly
- Not smoking
- Limiting alcohol intake
- Controlling blood pressure
- Controlling diabetes
- Checking cholesterol levels regularly
- Treating heart disease
- Taking prescribed medications for heart disease, high cholesterol, high blood pressure, or diabetes as directed
- Practicing stress reduction techniques such as meditation and yoga
U.S. Centers for Disease Control