Massive Stroke: Types, Recovery, and Long-Term Effects

Strokes, which affect around 795,000 Americans per year, occur when the brain is deprived of oxygen. This can happen either due to a blood clot that blocks blood flow (an ischemic stroke) or a ruptured blood vessel in the brain (a hemorrhagic stroke).

Strokes vary in their location and severity. A "massive" stroke is one that results in significant disability or even death.

Here's what to know about the different types of massive strokes and their potential long-term effects.

Patient sleeping while his wife sits next to him looking concerned
ImagesBazaar / Getty Images

Stroke Versus Massive Stroke

Any type of stroke can be severe enough to be considered massive. Some, however, are more likely than others to result in significant disabilities or death. The outcome depends on several factors, including:

  • The type of stroke
  • Which part of the brain is affected
  • How long it takes to get medical help

When administered within three hours of the first symptoms of an ischemic stroke, a drug called tPA (tissue plasminogen activator) can help dissolve the blood clot quickly and limit the amount of damage and disability.

Some doctors use the National Institutes of Health Stroke Scale to calculate a stroke "score." The score is based on an evaluation of a number of functional abilities or deficits in the patient. The higher the score, the more severe the stroke.


There are a few categories of strokes that are more likely to result in significant disability, coma, or death. Some are "sub-types" of an ischemic stroke. Ischemic stroke is the most common type, accounting for 87% of all strokes.

Ischemic Strokes

Ischemic strokes occur when a blood clot interrupts blood flow to the brain. Sub-types of ischemic strokes that are considered massive include:

Bilateral watershed stroke: Watershed strokes affect areas of the brain that are referred to as the "watershed areas." These areas receive their blood supply from the tiniest end branches of blood vessels. They require adequate blood pressure and blood volume to ensure that enough blood flows through them at all times.

Because of this, watershed areas on both sides of the brain are at high risk of developing ischemia, or lack of blood flow during certain conditions.

Advanced carotid stenosis (clogging of the neck arteries) on both sides of the neck is one of the risk factors for this type of stroke. Watershed strokes produce severe disability because they impact movement on both sides of the body.

Ischemia can occur during times of extremely low blood pressure, often caused by extreme blood loss, dehydration, heart attack, or sepsis.

Large thrombotic stroke: Thrombotic strokes are caused by large blood clots that form in an artery that feeds blood to the brain.

Middle cerebral artery stroke is an example of a severe thrombotic stroke. The swelling causes a rapid increase in pressure throughout the entire brain. This high pressure leads to:

  • Global brain dysfunction
  • Impaired consciousness
  • Brain herniation (significant pressure and pushing on the brain)
  • Death

Large embolic stroke: An embolic stroke occurs when a blood clot that forms in another area of the body (such as the heart or large arteries of the upper chest and neck) travels to the brain. The most severe embolic strokes are due to a clot that travels from the heart to the brain.

Large blood clots are especially dangerous because they can completely stop blood from flowing through the largest, and thus most important, blood vessels in the brain.

Hemorrhagic Strokes

Hemorrhagic strokes occur when an artery in the brain bursts, releasing blood into the brain. The blood increases the pressure inside the skull (called intracranial pressure) causing major damage to surrounding tissue. Hemorrhagic strokes account for 13% of strokes.

There are three types of hemorrhagic stroke, depending on where the bleeding occurs:

  • Subarachnoid hemorrhage (also called subdural hemorrhage) involves the rupture of a vessel on the surface of the brain. Blood seeps into the space between the brain and an area of tissue called the arachnoid layer, which surrounds the brain.
  • Parenchymal or intracerebral hemorrhage occurs when the bleeding goes directly into the brain tissue.
  • Intraventricular hemorrhage involves bleeding into or around the chambers (ventricles) that contain the cerebrospinal fluid that surrounds the brain and spinal cord.

Hemorrhagic strokes are extremely dangerous because the blood in the brain can sometimes lead to further complications such as:

  • Hydrocephalus, a build-up of fluid in the brain
  • Increased pressure inside the head
  • Blood vessel spasms

If not treated aggressively, these conditions can lead to severe brain damage and even death. This is why even minor episodes of bleeding in the brain require emergency evaluation.

Brainstem Stroke

The brainstem connects the brain to the spinal cord, and from there to the body. The brainstem controls many important functions, such as:

  • Breathing
  • Blood pressure
  • Heart rate

It also contains the brain's awareness center, which allows us to stay conscious. Brainstem strokes can be caused by a clot or a hemorrhage.

A brainstem stroke, even a small one, may lead to paralysis on one or both sides of the body. It can also cause changes in vision. Depending on the location of a stroke within the brainstem, it can result in long-term unconsciousness.​

Signs of a Stroke

The key signs of a stroke of any type are:

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


The most severe outcomes of a massive stroke include:


A massive stroke frequently results in complete paralysis on one side of the body, called hemiplegia. Hemiparesis, which is defined by weakness on one side of the body, is a less severe complication. A stroke that affects the left side of the brain will result in paralysis or weakness on the right side of the body, and vice versa.


Brainstem strokes in particular can cause a patient to end up in a coma, a state of unconsciousness. A stroke in the brain stem can leave someone in a “locked-in” state in which the person is paralyzed, cannot speak, and can only move the eyes up and down.

Brain Death

Sometimes severe strokes can produce so much damage to the brain that the brain becomes unable to function in a way that sustains life, which is a condition called brain death. This may occur after a very large stroke or after a stroke in a vital region of the brain, such as the brainstem.


Stroke is the number five cause of death in the United States. In some cases a stroke can be lethal instantly, or within days or weeks.

A person who has already had a stroke is at an increased risk of having another stroke, and a recurrent stroke is more likely to be fatal than the first one. Almost 25% of the strokes that occur in the United States each year are recurrent strokes.


Causes that are common to all types of stroke include:

Causes of hemorrhaghic strokes in particular include:


Recovering from a stroke can take several months or longer, and may involve the following:

  • Physical therapy: Physical therapy is intended to help people regain the ability to walk, stand, and sit. Physical therapists use exercises to restore balance and coordination.
  • Occupational therapy: Occupational therapists help stroke patients relearn skills needed to perform the activities of daily living, such as dressing, bathing, eating, and using the bathroom. Exercises as well as modifications to the home can contribute to success in this area,
  • Speech therapy: Speech therapy can help when a stroke results in difficulties forming words or understanding someone else when they are speaking.
  • Mental health counseling: It is common for people to experience depression, anxiety, and other mood changes after a stroke. Therapy, sometimes along with medication, can help ease some of these problems.

The first three months after a stroke are the most important and where the most significant improvements in regaining function are made, though gains can continue to be made for up to a year.

Therapy and medicine may help with depression or other mental health conditions following a stroke. Joining a patient support group may help you adjust to life after a stroke. Talk with your health care team about local support groups, or check with an area medical center.


Any stroke can potentially be severe. The chances of surviving a stroke or recovering completely depend on the type of stroke, the part of the brain involved, and how long it takes to get medical help.

Certain subtypes of stroke are more likely to be severe. This includes strokes that affect parts of the brain that receive blood from small blood vessels, those involving large blood clots, those that cause massive bleeding in the brain, and strokes that affect the brainstem.

Complications of a massive stroke can include paralysis, coma, and death. Recovering from a massive stroke can take months or longer.

A Word From Verywell

If you or a loved one has had one of these types of strokes, you may have a long recovery ahead, or even a long-lasting and substantial change in your abilities.

Many people do experience a degree of recovery, even from severe strokes. It may take some time for the stroke to stabilize and for you and your loved ones to gain an idea of what to expect as far as the long-term stroke outcome. Make sure to talk to your doctor about medications and lifestyle changes that can help prevent you from having another stroke.

Frequently Asked Questions

  • What causes a massive stroke?

    A stroke occurs when a blood vessel leading to the brain is either blocked by a blood clot or ruptures. When a stroke is lethal, or leaves a person severely impaired, it is considered a massive stroke.

  • What are the signs of a stroke?

    Signs that someone may be having a stroke include sudden drooping of one side of the face, slurred speech, weakness in one arm or leg, vision problems, trouble walking, and a severe headache with no known cause.

16 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention. Stroke.

  2. National Institute of Neurological Disorders and Stroke. Stroke: hope through research.

  3. National Library of Medicine. Thrombolytic therapy.

  4. Liberman AL, Zandieh A, Loomis C, et al. Symptomatic carotid occlusion Is frequently associated with microembolization. Stroke. 2017;48(2):394-399. doi:10.1161/STROKEAHA.116.015375

  5. Elsadek A, Gaber A, Afifi H, Farag S, Salaheldien N. Microemboli versus hypoperfusion as an etiology of acute ischemic stroke in Egyptian patients with watershed zone infarction. Egypt J Neurol Psychiatr Neurosurg. 2019;55(1):2. doi:10.1186%2Fs41983-018-0045-8

  6. Verschoof MA, Groot AE, Vermeij J, Association between low blood pressure and clinical outcomes in patients with acute ischemic stroke. Stroke. 2020;51:338–341. doi:10.1161/STROKEAHA.119.027336

  7. Walcott BP, Miller JC, Kwon CS, et al. Outcomes in severe middle cerebral artery ischemic stroke. Neurocrit Care. 2014;21(1):20-6. doi:10.1016/j.ncl.2014.07.006

  8. American Stroke Association. Hemorrhagic stroke (bleeds).

  9. American Stroke Association. Brain stem stroke.

  10. Ortiz de Mendivil A, Alcalá-Galiano A, Ochoa M, Salvador E, Millán JM. Brainstem stroke: anatomy, clinical and radiological findings. Semin Ultrasound CT MR. 2013;34(2):131-41. doi:10.1053/j.sult.2013.01.004

  11. National Organization for Rare Diseases. Locked-in syndrome.

  12. American Stroke Association. About stroke.

  13. Khanevski AN, Bjerkreim AT, Novotny V, et al. Recurrent ischemic stroke: Incidence, predictors, and impact on mortality. Acta Neurol Scand. 2019;140(1):3-8. doi:10.1111/ane.13093

  14. Oza R, Rundell K, Garcellano M. Recurrent ischemic stroke: strategies for preventionAm Fam Physician. 2017;96(7):436-440

  15. Johns Hopkins Medicine. Stroke recovery timeline.

  16. American Stroke Association. Stroke symptoms.

Additional Reading

By Jose Vega MD, PhD
Jose Vega MD, PhD, is a board-certified neurologist and published researcher specializing in stroke.