Preserve mental capacity
In addition to improving survival and reducing disability, mechanically removing the clot causing an ischemic stroke leads to better cognitive functioning, according to research presented at the American Stroke Association’s International Stroke Conference 2016.
Ischemic strokes account for about 85% of all stroke types and are caused by a blockage of blood flow in an artery leading to brain tissue. When the blockage occurs, the brain tissue that is not getting enough blood flow will start to become permanently injured. Restoring blood flow to the brain tissue at risk of injury is the first priority in an ischemic stroke. The first treatment to try and open the vessel is the use of a medication to break the clot up. This medication is called intravenous recombinant tissue-type plasminogen activator (r-tPA) or alteplase. The earlier this medication is administered the more likely it can open the vessel before there is permanent brain tissue loss.
Endovascular Reperfusion Therapy
In some cases, the blockage may not be opened up with the use of tPA (alteplase) alone. Many strokes occur as the result of blockage of a large artery and there is more brain tissue at risk of injury. In these types of stroke, the symptoms are likely to be the even more severe. For some patients that have a large vessel occlusion, a second line therapy must be considered. This is called mechanical endovascular reperfusion therapy.
As in the use of intravenous tPA, mechanical endovascular reperfusion therapy must be provided as early as possible to provide the most benefit to those who are suffering an ischemic stroke.
This treatment may only be offered by physicians who have received advanced training in neuro endovascular treatments. Greenville Memorial Hospital is currently the only hospital in the upstate of South Carolina with the physicians and resources needed to offer this treatment.
Other Conditions May be Treated With Endovascular Therapy
About 3-5% of strokes occur as a result of a cerebral aneurysm that ruptures and bleeds into the area surrounding the brain. When this happens it is called a stroke caused by subarachnoid hemorrhage. A cerebral aneurysm occurs when the artery wall becomes weak and balloons out. This weak area has a greater risk of rupture allowing blood to leak out of the artery into the surrounding tissue.
Treatment of cerebral aneurysms may include either surgery or endovascular treatment. This is done to reduce the chances that the aneurysm will leak or rupture.
- An estimated 6 million people in the United States have an unruptured brain aneurysm, or 1 in 50 people.
- The annual rate of rupture is approximately 8 – 10 per 100,000 people or about 30,000 people in the United States suffer a brain aneurysm rupture. There is a brain aneurysm rupturing every 18 minutes. Ruptured brain aneurysms are fatal in about 40% of cases. Of those who survive, about 66% suffer some permanent neurological deficit.
- Approximately 15% of patients with aneurysmal subarachnoid hemorrhage (SAH) die before reaching the hospital. Most of the deaths from subarachnoid hemorrhage are due to rapid and massive brain injury from the initial bleeding which is not correctable by medical and surgical interventions.
- 4 out of 7 people who recover from a ruptured brain aneurysm will have disabilities.
- Brain aneurysms are most prevalent in people ages 35 – 60, but can occur in children as well. The median age when aneurysmal hemorrhagic stroke occurs is 50 years old and there are typically no warning signs. Most aneurysms develop after the age of 40.
- Women, more than men, suffer from brain aneurysms at a ratio of 3:2.
- Ruptured brain aneurysms account for 3 – 5% of all new strokes.
- Accurate early diagnosis is critical, as the initial hemorrhage may be fatal, may result in devastating neurologic outcomes, or may produce minor symptoms. Despite widespread neuroimaging availability, misdiagnosis or delays in diagnosis occurs in up to 25% of patients with subarachnoid hemorrhage (SAH) when initially presenting for medical treatment. Failure to do a scan results in 73% of these misdiagnoses. This makes SAH a low-frequency, high-risk disease.
- Subarachnoid hemorrhage (SAH) is one of the most feared causes of acute headache upon presentation to the emergency department. Headache accounts for 1 – 2% of the emergency room visits and up to 4% of visits to the primary care offices. Among all the patients who present to the emergency room with headaches, approximately 1% has subarachnoid hemorrhage. One study put the figure at 4%.
- There are almost 500,000 deaths worldwide each year caused by brain aneurysms and half the victims are younger than 50.
Early Detection and Screening
Brain aneurysms can be similar to heart attacks. Just like a person may have no warning of an impending heart attack, there almost is never a warning that a brain aneurysm is about to rupture. Fortunately, through imaging screening techniques, individuals at high risk of harboring a brain aneurysm can be identified easily with non-invasive imaging tests.
Risk factors for developing brain aneurysms include cigarette use, disorders of the body’s structural proteins (Ehlers-Danlos syndrome, Marfan syndrome), fibromuscular dysplasia, chronic hypertension, history of cerebral aneurysms in closely related family members, use of cocaine, crack or amphetamines and polycystic kidney disease.
If two or more members of the family are affected with brain aneurysms, then aneurysm screening (with brain MRA or brain CTA) is usually recommended for at least the first degree relatives over the age of 25 of those affected.
Risk factors that doctors and researchers believe contribute to the formation of brain aneurysms:
- High blood pressure or hypertension
- Congenital resulting from inborn abnormality in artery wall
- Family history of brain aneurysms
- Age over 40
- Gender, women compared with men have an increased incidence of aneurysms at a ratio of 3:2
- Other disorders: Ehlers-Danlos Syndrome, Polycystic Kidney Disease, Marfan Syndrome, and Fibromuscular Dysplasia(FMD)
- Presence of an arteriovenous malformation (AVM)
- Drug use, particularly cocaine
- Traumatic head injury
Arteriovenous Malformation (AVM)
When an arteriovenous malformation (AVM) occurs, a tangle of blood vessels in the brain, or on its surface bypasses normal brain tissue and directly diverts blood from the arteries to the veins.
In some cases, a weakened blood vessel may burst, spilling blood into the brain (hemorrhage) that can cause stroke and brain damage. Other neurological problems include headache, weakness, seizures, pain, and problems with speech, vision, or movement. In most cases, people with neurological AVMs experience few, if any, significant symptoms.
It is unclear why AVMs form. Most often AVMs are congenital, but they can appear sporadically. In some cases the AVM may be inherited, but it is more likely that other inherited conditions increase the risk. The malformations tend to be discovered only incidentally, usually during treatment for an unrelated disorder or at autopsy. It is estimated that brain AVMs occur in less than one percent of the general population; each year about one percent of those with AVMs will die as a direct result of the AVM.
Normally, arteries carry blood containing oxygen from the heart to the brain, and veins carry blood with less oxygen away from the brain and back to the heart. When an arteriovenous malformation (AVM) occurs, a tangle of blood vessels in the brain or on its surface bypasses normal brain tissue and directly diverts blood from the arteries to the veins.
Brain AVMs occur in less than 1 percent of the general population. It’s estimated that about one in 200–500 people may have an AVM, which is more common in males than in females.
Brain AVMs are usually congenital, meaning someone is born with one. But they’re usually not hereditary. Brain AVMs can occur anywhere within the brain or on its covering.
Symptoms may vary depending on where the AVM is located.
- More than 50 percent of patients with an AVM have an intracranial hemorrhage.
- Among AVM patients, 20 percent to 25 percent have focal or generalized seizures.
- Patients may have localized pain in the head due to increased blood flow around an AVM.
- Fifteen percent may have difficulty with movement, speech and vision.
If an AVM bleeds, it can affect one or more normal body functions, depending on the location and extent of the brain injury. Different locations in the brain control different functions. An AVM may be considered for treatment if it has bled, if it’s in an area of the brain that can be easily treated, and if it’s not too large.