What Happens During a Stroke?

A stroke is loss of blood flow to part of the brain. It happens when a blood clot blocks an artery in the brain or when a bleed from a blood vessel in the head creates pressure in the brain.

In either case, brain cells die, and the brain is damaged temporarily or permanently. Depending on the area of brain deprived of oxygen, a person may experience loss of memory, movement, speech or other disabilities. If blood flow is restored or pressure is relieved quickly through medical treatment, the brain may fully recover.

Learn more as neurointerventionalist John Terry, MD, discusses “What is a Stroke?”

Click play to watch the video or read the transcript.

What is a stroke?

Well stroke is primarily a process that has to do with problems in the brain or spinal cord that arise from blood vessel issues, and specifically loss of blood flow to part of the brain or spinal cord. And that can happen in two fundamentally different ways. The first is that a blood clot can form in the blood vessel that plugs it off so that flow doesn't happen and therefore the part of the brain or spinal cord where the blood was going to go doesn't get blood and it starts not functioning properly. And if this goes on for more than minutes to hours, you can end up getting permanent damage to the tissue. The other form of stroke involves a blood vessel that breaks and bleeds. That blood creates a pool in the brain, and that can cause damage. Plus that blood was destined to go to some part of the brain, and it's obviously not going there if it's leaking out.

 

Stroke is among the top five causes of death and a leading reason for disability in Americans, according to the American Stroke Association. Close to 800,000 people in the U.S. have a stroke each year, and there are nearly seven million stroke survivors in the U.S.

If blood flow is restored or pressure is relieved quickly through medical treatment, the brain may fully recover.

Two Types of Stroke: Ischemic and HemorrhagicWhat Happens During a Stroke? - In Content

Ischemic stroke. This type of stroke occurs when a blood clot blocks the flow of blood to the brain. The clot may have traveled from another part of the body (called an embolus) or formed inside an artery that supplies blood to the brain (called a thrombus).

Strokes that result from a blood clot make up about 87 percent of all strokes, according to the American Stroke Association. Medications that dissolve a clot can prevent severe damage if given quickly after stroke symptoms appear.

Hemorrhagic stroke. When a blood vessel in the brain breaks or leaks due to weakness in the vessel wall, blood flows into or around the brain and creates swelling and pressure. This bleeding (or hemorrhage) damages brain cells and tissue.

Strokes from bleeding make up about 13 percent of all strokes, says the American Stroke Association, but they are the most deadly, causing about 40 percent of stroke deaths, according to the National Stroke Association.

“When a loved one or a family member has a stroke, knowing which type is really important for the physician because the treatment and the care is really different,” says neurointerventionalist Bryan Ludwig, MD, Premier Health Neuroscience Institute. Dr. Ludwig answers “Are there different kinds of stroke?”

Click play to watch the video or read the transcript.

Are there different kinds of stroke?

So there are two different types of stroke categories, one being the bleeding type stroke or what we call a hemorrhagic stroke. The second one being a blood flow stroke or an ischemic is the medical term, ischemic stroke. Those two categories encompass what most people talk about when they say the word stroke. And so it's important to remember that when a loved one or when a family member has a stroke, knowing which type is really important for the physician because the treatment and the care is really different.

 

Effects of Stroke

Stroke affects the brain in different ways, depending on the part of the brain that is deprived of oxygen or put under pressure by excessive bleeding. The amount of time that passes before the stroke is treated also impacts the extent of damage to the brain.

A small stroke or one that is treated quickly may cause only minor problems such as temporary weakness of an arm or leg. A more serious stroke may cause permanent paralysis on one side of the body or loss of speech or memory. Some people recover completely from strokes, but the National Stroke Association says more than two-thirds of survivors will have some type of disability.

Schedule an appointment

To find a neurologist or primary care provider, call (866) 608-FIND(866) 608-FIND or complete the form below to receive a call from our call center to schedule an appointment.