Stroke, Demystified

Stroke kills 140,000 Americans each year and is the leading cause of serious and long-term disability. Stroke can affect all people, regardless of age or gender.

Despite the prevalence and seriousness of stroke, however, many Americans are not aware of what exactly a stroke is — or the steps they can take to prevent one. Here are answers to the most common questions about this common disease.

What is a stroke?

A stroke occurs when the blood flow to the brain is obstructed, depriving brain tissue of oxygen and nutrients.

A stroke can occur anywhere in the brain, including the spinal cord. The severity depends on its location and size.

Dr. Babak Navi, Associate Professor of Neurology and Neuroscience at Weill Cornell Medicine and Medical Director of the Weill Cornell Stroke Center, explained that “within minutes of a stroke, there is irreversible brain injury as brain cells begin to die. Time is brain, literally. Therefore, it is critical to call 911 to get access to life-saving treatments that are only available in a hospital.”

Ischemic stroke: About 85 percent of strokes are ischemic strokes, which are caused by a blood clot interrupting blood flow to a region of the brain.

There are two types of ischemic stroke:

• Embolic strokes are caused when a blood clot is formed elsewhere in the body and travels to arteries in the brain.
• Thrombotic strokes are caused when a blood clot occurs in the brain itself.

Hemorrhagic stroke: This less common type of stroke occurs when a blood vessel in the brain leaks or ruptures, causing bleeding in or around the brain. There are two main categories of hemorrhagic stroke:

• Intracerebral hemorrhage is bleeding within the brain.
• Subarachnoid hemorrhage is bleeding within the space between the brain and the membranes surrounding it (the subarachnoid space). 

“A stroke, particularly those that resolve spontaneously (TIAs), can be a harbinger of a second stroke, which can often be more severe or damaging than the first,” warned Dr. Navi. “Therefore, it’s important to get treatment as soon as possible so that a second stroke can be prevented.”

What are the signs of stroke?

The most common symptoms or signs of stroke include:

     ●         Speech impairments

     ●         Numbness or weakness of one side

Less common symptoms include:

     ●         Imbalance (trouble walking)

     ●         Dizziness or vertigo (young people tend to experience these)

     ●         Vision changes

     ●         Sudden severe headache

     ●         Confusion or reduced consciousness

Call 911 immediately if you experience these symptoms or any new, unexplained neurological condition.

How should I get help for a stroke? 

Dr. Navi cautioned, “You shouldn’t first visit your primary care doctor or other health care professional. You shouldn’t sleep on it. Symptoms may be mild in the beginning, but they can progress very quickly. Don’t ignore them.”

If you have a new, unexplained neurological condition, call 911 immediately.

He suggested stating directly that you believe it could be a stroke or “brain attack.” Be sure to clearly explain that you or your loved one was normal one moment and could not speak, move, or balance the next.

Mobile stroke unit: Weill Cornell Medicine has several mobile stroke units, which have been shown to reduce the treatment time for a stroke by about 30 minutes. “Because the patient bypasses travel to the hospital and is seen immediately by a stroke specialist,” asserted Dr. Navi, “the mobile stroke unit is expected to lead to better long-term neurological outcomes.” 

Monday through Friday, Weill Cornell Medicine mobile stroke units treat suspected stroke patients throughout New York City. A stroke nurse, radiology technician, and two paramedics work on the ambulance, and a stroke neurologist evaluates patients remotely through telemedicine. An exam and CT scan are performed on the ambulance and, if appropriate, treatment is administered immediately.

How is stroke treated?

When a stroke patient arrives at a hospital for treatment, he or she is evaluated by a team of stroke specialists to determine the stroke’s type and location.

Tissue plasminogen activator (tPA) is the only FDA-approved treatment for ischemic stroke. (It is not used for hemorrhagic stroke.) Unfortunately, tPA is given to a minority of stroke patients because they don’t get to the hospital on time or cannot have it.

“tPA is a clot buster or blood thinner,” said Dr. Navi. “The key is doing things quickly, but also safely. The goal ‘door to needle time’ is 60 minutes. We have been meeting that for 90 percent of our patients. We tend to do so within 40 minutes. We’re getting faster every year.”

Additional imaging or treatment may be needed to restore blood flow through the blocked artery and minimize the effects of the stroke. After treatment, the patient is taken to an intensive care unit to be monitored for brain swelling, infections, and blood clots.

Again, seeking immediate medical attention is critical. After a stroke, parts of the brain begin to swell, which can cause a severe increase in pressure within the brain or even lead to a second brain injury. This can be more damaging than the stroke itself.

What happens after treatment?

After receiving treatment for a stroke, stroke specialists develop a personalized strategy for preventing a second stroke. This may include medications or lifestyle changes.

A stroke can cause physical and mental disabilities, making it harder to live independently. The care team at Weill Cornell Medicine helps stroke patients access the services and resources needed to pursue an active and rewarding life, including social services, cognitive behavioral therapy, and physical therapy. 

How can stroke be prevented?

You can prevent a stroke by achieving and maintaining good cardiovascular health. To do this, it is important to:

     ●         Maintain a healthy weight

     ●         Get 30 minutes or more of moderate activity daily

     ●         Quit smoking

     ●         See your primary care doctor regularly to check for diabetes and high blood pressure

     ●         Eat a healthy diet

     ●         Limit alcohol consumption (one to two  drinks per day)

Learn more about The Stroke Center at Weill Cornell Medicine and read a stroke survivor’s story about receiving treatment at Weill Cornell Medicine.