Emergent Stroke Therapy Procedures
Emergent Stroke Therapy
is the third leading cause of death in the United States behind high
blood pressure and cancer. Every 45 seconds someone in the United States
has a stroke and every three minutes someone dies from a stroke. In the
U.S. alone, an estimated 600,000 individuals will suffer a new or
recurrent stroke each year --160,000 will die. More than one million
American stroke survivors struggle with serious disabilities, including
loss of speech and/or language problems, weakness or paralysis, loss of
balance or coordination, and confusion and memory loss. All are common
impairments in the aftermath of a stroke.
Once it was believed
that little could be done to treat stroke. Now we know that if a stroke
victim receives emergency care within the first three to six hours of
the first symptom, the disabling, long-term effects of stroke may be
avoided or greatly reduced. Unfortunately, many people do not recognize
the warning signs of stroke or do not know that immediate emergency care
can greatly improve their chance of recovery.
Studies show that
the average person waits 13 hours after experiencing the first symptoms
of stroke before seeking medical care, and 42 percent of patients wait
as long as 24 hours. It is critical to recognize the symptoms of stroke
and seek immediate emergency attention. What causes stroke?
A stroke occurs when a blood vessel carrying oxygen and nutrients
to the brain is blocked by a clot or bursts, causing the brain to
starve. If deprived of oxygen for even a short period of time, the brain
nerve cells will start to die. Once the brain cells die from a lack of
oxygen, the part of the body that section of the brain controls is
affected through paralysis, language, motor skills, or vision.
There are two types of stroke:
- Blood clots that block the artery are ischemic (is-KEM-ik) strokes
and the most common type, causing between 70-80 percent of all strokes.
- Second type is when a blood vessel ruptures, it causes a bleeding or
hemorrhagic (hem-o-RAJ-ik) stroke. Such strokes are usually the result
of a ruptured blood vessel or an aneurysm (a weakened area of a blood
vessel that bulges or balloons out).
Sometimes, abnormal tangles of blood vessels in the brain, called
arteriovenous malformations (AVM) can rupture and cause a hemorrhagic
stroke. Approximately 20 percent of strokes are hemorrhagic. This is the
most common type of stroke in young people.
are also "mini-strokes" known as TIA's "Transient Ischemic Attacks."
People who have one TIA are likely to have another one. TIAs cause brief
stroke symptoms that go away after a few minutes or hours. People often
ignore these symptoms, but they are an early warning sign, and 35
percent of those who experience a TIA will have a full blown stroke if
left untreated. TIAs should be taken as seriously as stroke. What are the symptoms of stroke?
The most common symptoms of stroke are:
- Sudden numbness or weakness in the face, arm and/or leg, especially on one side of the body.
- Sudden confusion, trouble speaking or understanding speech
- Sudden trouble seeing, including double vision, blurred vision or partial blindness, in one or both eyes
- Trouble walking, dizziness, loss of balance or coordination
- Sudden severe, headache with no known cause
If you experience any of these symptoms, even if they go away quickly, seek immediate emergency help.
Every minute counts!
Although starved of oxygen, brain tissue does not die in the
minutes following a stroke. If blocked blood vessels can be opened
within three to six hours, the chances of recovery are greatly improved.
What are the risk factors for stroke?
People who are at higher-than-average risk for stroke include those who have:
High blood pressure, or hypertension, puts stress on the walls of
blood vessels and can lead to strokes from blood clots or hemorrhage.
Half or more of all stroke victims have uncontrolled high blood
pressure. Fortunately, this risk factor for stroke can be controlled.
Eating a balanced diet, maintaining a healthy weight and exercising
regularly can help control high blood pressure. Medications that lower
blood pressure also may be prescribed.
High cholesterol can lead to blockage in the carotid artery that
takes blood from the neck to the brain. A piece of this plaque can break
off and travel to the brain causing a stroke.
Approximately 15 percent of all stroke victims have a common heart
rhythm disorder called atrial fibrillation, that causes the upper
chambers of the heart (the atria) quiver instead of beating which allows
the blood to pool and clot. If a clot breaks off and enters the
blood stream to the brain, a stroke will occur
When the carotid arteries, the major blood vessels that supply
blood to the brain, become clogged with atherosclerotic plaque, the risk
for stroke goes up.
- Personal history of stroke or TIA
People who have already suffered a stroke or TIA are at increased
risk of having another. Modifying risk factors for stroke,
including lifestyle changes (e.g. exercise, stop
smoking), medications and/or other treatments can reduce this risk.
Smoking, excessive alcohol consumption and being overweight are all
significant risk factors for stroke. High cholesterol can lead to
blockage in the carotid artery that takes blood from the neck to the
brain. A piece of this plaque can break off and travel to the brain
causing a stroke.
The risk of stroke goes up with age, with two-thirds of all strokes
occurring in individuals 65 years or older. Twenty-eight percent of
stroke occur in people under the age of 65. Males have a slightly higher
risk than females although more women die from them. African
Americans are at a much higher risk in part because they are at
increased risk for obesity, high blood pressure and diabetes which
increase the risk for stroke.
- Family history of stroke or TIA
If others in your family have suffered stroke, you may be at higher
risk. Regular physical exams, lifestyle changes and medical treatments
may reduce this risk.
People with diabetes are at increased risk for stroke, although
keeping diabetes under control with diet and/or medication may help to
decrease the risk.
Sickle cell anemia makes red blood cells less able to carry
blood to the body's tissues and organs, as well as stick to the walls of
the blood vessels which can block arteries to the brain causing a
Elevated homocysteine levels in the blood have been identified as a
risk factor for heart attack and stroke that may be as important as
high cholesterol. Homocysteine is a by-product of the process that
metabolizes methionine, an amino acid essential in human nutrition.
Stroke Prevention - Carotid Stenting - Carotid Artery Screening
As vascular experts, interventional radiologists treat
atherosclerosis, or "hardening of the arteries," throughout the body.
In some patients, atherosclerosis, specifically in the carotid artery in
the neck, can lead to ischemic stroke. Plaque in the carotid artery may
result in a stroke by either decreasing blood flow to the brain or by
breaking loose and floating into a smaller vessel, depriving a portion
of the brain of blood flow. In patients at high risk of having a stroke,
the narrowed section of the artery may be reopened by an interventional
radiologist through angioplasty and reinforced with a stent, thereby
preventing the stroke from occurring. Vascular stents are typically made
of woven, laser-cut or welded metal that permits the device to be
compressed onto a catheter and delivered directly into the hardened
artery. In addition to diagnosing and treating those at risk for stroke,
interventional radiologists can use their expertise in imaging,
angioplasty, and stenting to treat those having an acute stroke.
Patients can also take action to prevent stroke by:
- Quitting smoking
- Controlling high blood pressure
- Lowering cholesterol levels
- Maintaining a healthy weight
- Utilizing appropriate medications such as aspirin and prescription drugs such as anticoagulants
- Treating carotid artery disease
- Treating unruptured cerebral aneurysms or arteriovenous malformations
If the stroke is due to a blood clot, a clot-busting drug, tPA (tissue plasminogen activator) can
be given intravenously to break up or reduce the size of blood clots to
the brain. This technique must be performed within three hours from the
onset of symptoms.
When therapy cannot be initiated within three hours or when treatment
with tPA during the first three hours is not sufficient to dissolve the
blood clot, interventional radiologists (IR) that specialize in
neurological procedures can provide intra-arterial thrombolysis
Using x-ray guidance, an IR will insert a catheter through a nick in
the skin at the groin and advance it through the femoral artery in the
leg all the way to the tiny arteries in the brain where they place the
clot-busting drug directly on the clot or to break up the clot
When given locally this way, the tPA can be administered up to six hours after
the onset of stroke symptoms. In many cases, the ambulance drivers will
take a stroke victim past the three-hour window directly to the
interventional radiology suite for assessment for this direct
thrombolytic therapy. Often, a significantly disabled stroke patient who
receives this treatment can return to normal life with minimal or no
after effects from the stroke.
The interventional radiologist will also assess what caused the clot,
such as a clogged carotid or other artery, and can correct the
underlying problem to prevent future strokes from occurring.
Unfortunately, many hospitals in this country do not have stroke teams
that can rapidly assess patients and provide treatment within the
three-hour window. Interventional radiologists are actively involved in
creating more stroke teams across the country. Stroke teams generally
consist of emergency room physicians, neurologists and interventional
Before tPa therapy
After tPa therapy
neuroradiologists can also treat ruptured aneurysms inside the brain
causing hemorrhage into the subarachnoid space, which can cause stroke
or death. During the embolization technique, an interventional
neuroradiologist inserts a catheter through a nick in the skin of the
groin and advances it to the site of the ruptured blood vessel. An
embolizing agent (a substance that clots or closes off the bleeding
blood vessel) is injected under X-ray guidance. Most commonly, tiny
metal coils are used to embolize and block the abnormal blood vessel or
aneurysm. The catheter is withdrawn and the coils remain to provide the
occlusion. The same technique can be used to treat aneurysms and AVMs
before they rupture. Surgery had been the primary treatment available
until the platinum coil device was approved by the FDA in 1995.