Ischemic stroke is the most common type of stroke. Here, we break down:
What is an ischemic stroke?
Ischemic stroke vs hemorrhagic stroke: What's the difference?
Ischemic stroke symptoms
Ischemic stroke causes
Ischemic stroke treatments
Ischemic stroke recovery
What is an ischemic stroke?
An ischemic stroke occurs when there is a blockage of blood flow to part of the brain. This blockage leads to decreased blood flow and prevents the brain tissue from getting the oxygen and nutrients it requires, resulting in temporary or permanent brain injury. The blood vessel blockage in an ischemic stroke can be thrombotic (where a blood clot forms in an artery going to your brain) or embolic (where a wandering blood clot, called an embolus, is formed elsewhere in your body — usually the heart or neck — and travels up to the brain to block an artery).
Ischemic stroke vs hemorrhagic stroke: What's the difference?
In contrast to an ischemic stroke, a hemorrhagic stroke occurs when a blood vessel in the brain breaks or ruptures and there is bleeding into the brain tissue (called an intracerebral hemorrhage) or around the brain tissue (called a subarachnoid hemorrhage). While hemorrhagic strokes are less common than ischemic strokes, they can also lead to brain injury.
Ischemic stroke symptoms
The symptoms caused by an ischemic stroke will depend on which area of the brain is affected because different areas of the brain are in charge of different functions. These symptoms will typically occur suddenly and rapidly. Some of the following symptoms can be seen either alone or in combination with others. These symptoms may include:
Face weakness (facial droop)
Arm weakness (typically on one side)
Leg weakness (typically on one side)
Numbness of one-half of the body
Sudden vision loss in one eye
Slurred speech
Inability to find the right words or speak the right words
Imbalance when walking or problems with coordination
Difficulty swallowing
Ischemic stroke causes
There are many different potential causes of ischemic stroke. A workup for the common causes of stroke can be done in the hospital or in the clinic setting, and then expanded to include more rare causes of stroke if needed.
As a doctor specializing in vascular neurology and stroke at Northwestern Medicine Palos Hospital, some of the potential causes for ischemic stroke I see include:
Long-standing high blood pressure
Plaque or cholesterol buildup in the arteries, which can lead to narrowing and ultimately blockage of arteries in the neck or brain
Abnormal heart rhythms, like atrial fibrillation
Blood clots caused by cancers
Injury to the arteries leading to the brain, called a dissection
Drugs of abuse
Infection of the heart valves
Genetic disorders that make people more susceptible to certain types of strokes
Unknown cause
Ischemic stroke treatments
Brain injury during an ischemic stroke results within minutes to hours after the blood vessel blockage occurs. The goal of acute stroke treatment is to resolve the blockage as quickly as possible after it starts. There are treatments available to do this, but they are only available in a certain timeframe and at the hospital, so it is important to call 911 and go to the closest hospital as soon as you notice symptoms concerning a stroke.
IV thrombolysis
Intravenous (IV) tissue plasminogen activator, either alteplase or tenecteplase, is a clot-busting medication that is administered through an IV, and it can help dissolve blood clots and improve blood flow to the part of the brain being affected by a stroke.
If eligible, you can receive this medication up to 4.5 hours from your last known normal. The last known normal is the date and time at which you were last known to be without signs or symptoms of a stroke, or at your previous neurologic baseline. This may mean that if you wake up with stroke symptoms, your last known normal was when you went to bed the night before, if you were asymptomatic at that time.
Patients who receive IV thrombolysis need to be monitored closely in the hospital for at least 24 hours.
Mechanical thrombectomy
When someone is having a stroke that is caused by a large blood vessel being blocked in the neck or the brain, they may be a candidate for a procedure called a mechanical thrombectomy to physically remove this blood clot. In a mechanical thrombectomy, a small catheter (tube) is inserted into a large blood vessel in the wrist or groin, and the catheter is threaded through the arteries up to the brain to the area of the blockage. Then suction and a wire-cage device, called a stent retriever, is used to grab onto the clot and remove it. After this, the entire device is removed from the artery. This procedure can be done up to 24 hours from the last known normal in some patients.
Ischemic stroke recovery
After an ischemic stroke, the brain can adapt and form new networks to help restore function. However, this process takes time, and it can be difficult to predict how much function will return and over what time period. The recovery period after a stroke is typically measured in months, sometimes up to 6 to 12 months after the stroke, though some patients will see some recovery in shorter time periods.
Depending on the symptoms caused by an ischemic stroke, patients may work with a variety of professionals as part of their rehabilitation team.
Physical therapists work with patients to help improve movement and restore function, including strength, coordination, balance and walking.
Occupational therapists help patients adapt to new limitations in function and increase independence in activities of daily living, like bathing, dressing and writing.
Speech language pathologists provide therapy for those with difficulties in communication as well as swallowing.
Patients may also work with a physical medicine and rehabilitation doctor.
This team of therapists and doctors will evaluate a stroke patient’s function and create a therapy plan to help maximize their recovery. This may include ongoing intensive rehabilitation at an inpatient rehabilitation facility, outpatient rehabilitation services or services at home.
