Nonsurgical Procedures Open Blocked Arteries to Prevent and Treat Stroke
Stroke 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 United States alone, an estimated 600,000 individuals will have 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.
Pop-up blockers will need to be disabled to view the animations.
For more 3D Medical Animations click here.
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’s nerve cells will start to die. Once the brain cells die from a lack of oxygen, the part of the body that that section of the brain controls is affected – paralysis or loss of language skills, motor skills or vision.
There are two types of stroke:
- Blood clots that block the artery are ischemic strokes and the most common type, causing between 70-80 percent of all strokes.
- When a blood vessel ruptures, it causes a bleeding or hemorrhagic stroke. Such strokes can also be the result of 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.
There are also "mini-strokes" known as TIAs (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.
A leading cause of stroke and TIA is carotid artery disease (CAD). In CAD, a substance called plaque builds up over time in the carotid arteries, the large blood vessels on either side of the neck that supply blood to the head and brain. The buildup of plaque is a silent disease, until small particles break away and are carried to smaller arteries, where they block the flow of blood. The nature and severity of symptoms depend on how large an area of the brain is affected and whether the blood supply to the brain is completely or partially blocked.
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. 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. 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.
- Heart disease. 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) to 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.
- Atherosclerosis. 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 had a stroke or TIA are at increased risk of having another. Modifying risk factors for stroke, including lifestyle changes (e.g., exercising, stopping smoking), medications and/or other treatments can reduce this risk.
- Lifestyle risk factors. 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.
- Age, gender and race. 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 strokes 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.
- Diabetes. 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. Sickle-cell anemia makes red blood cells less able to carry blood to the body's tissues and organs, and causes them to stick to the walls of the blood vessels, which can block arteries to the brain causing a stroke.
- Hyperhomocysteinemia. 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.
Reprinted with permission of the Society of Interventional Radiology © 2004, www.SIRweb.org. All rights reserved.