Stroke is one of the leading causes of death in the United States. Someone has a stroke nearly every 40 seconds yet only 38% of Americans know all of the major symptoms of this dangerous disease. Today, we’ll explore the causes, types, symptoms, diagnosis, and treatments.
Cause
The cause of a stroke is widely known, the blockage of blood supply to your brain, but the conditions that result in this situation vary among individuals. When the blood supply to your brain is blocked, whether it be a major or minor artery, brain cells begin to die immediately, making the time between the onset of symptoms and treatments crucial.
Strokes are often caused by conditions such as atrial fibrillation, atherosclerosis, and high blood pressure. These conditions put immense pressure on the arteries throughout the body, increasing the risk of a blockage. Some other less common causes include noninflammatory/inflammatory blood vessel disorders, hematological disorders, migraine-related stroke, and cerebral venous thrombosis. Blood vessel disorders cause vasospasms, the build-up of lipids among artery walls, or inflammation in the cerebrovascular system. Hematological disorders cause genetic changes to the clotting mechanisms of the blood, leading to an increased risk of hemorrhages or artery blockage. Migraines are caused by changes in the functions of platelets and the cells that line of blood vessels. These migraines are often linked to an increased risk of stroke, especially in women. Cerebral venous thrombosis is a very rare cause of stroke but can occur in both children and adults. It is usually linked to some sort of infection but can also occur in pregnant women. The underlying condition needs to be treated first before the stroke can be addressed.
Risk Factors:
Some risk factors of stroke can not be changed: age, gender (women are significantly more likely to suffer a stroke), family history, race (African-Americans have a higher risk than Caucasians), and prior stroke.
Controllable risk factors include high blood pressure, smoking, diabetes, diet, physical inactivity, obesity, heart diseases (such as Carotid Artery Disease), high levels of cholesterol. These factors can be affected and used to help prevent strokes, especially in those predisposed to have one.
Types
Ischemic Stroke:
An ischemic stroke occurs when an artery in the brain is blocked due to a clot. This may be caused by a fatty deposit lining the walls (atherosclerosis) that travels to cerebral arteries or clots in the left arterial appendage. The fatty deposits can cause two types of obstruction: cerebral thrombosis or cerebral embolism. Cerebral thrombosis is a thrombus (blood clot) that develops at the fatty plaque within the blood vessel. A blood clot that forms in another location, breaks loose, enters the bloodstream and travels to the brain is known as cerebral embolism. This is normally caused by atrial fibrillation. This is what occurs in the left arterial appendage; the cerebral arteries experience cerebral thrombosis. This type of stroke is the most common, accounting for over 87% of all strokes.
Hemorrhagic Stroke:
This type accounts for 13% of all strokes. A hemorrhagic stroke occurs when a blood vessel in the brain is weakened and breaks - causing blood to leak into the surrounding brain. The blood accumulates and puts pressure on the delicate brain tissue. There are two types of hemorrhagic stroke: intracerebral or subarachnoid. This is usually caused by high blood pressure or side effected of blood-thinning anticoagulant drugs.
There are two types of blood vessels that are usually involved: arteriovenous malformations and aneurysms. Arteriovenous malformations (AVM) are a congenital disorder that causes a tangle in blood vessels. The blood bypasses the brain tissue and directly flows from arteries to veins. These blood vessels are weakened and can burst from high blood pressure. Over 50% of patients with this condition experience intracerebral hemorrhages or seizures. An aneurysm is a weak enlarged area of a blood vessel that is susceptible to ruptures. This is not usually a congenital disease but develops after the age of 40. These points are often put under lots of pressure from blood pressure, slowly weakening the junction. It causes bleeding into the space around the brain - a subarachnoidal hemorrhage.
TIA (Transient Ischemic Attack):
A TIA is also known as a mini-stroke because it caused by a temporary blockage. The damage is often temporary but over 33% of people who experience a TIA will go on to have a more serious stroke later.
Cryptogenic Stroke:
In some cases, the cause of a stroke is indeterminable. These strokes are known as cryptogenic and can show warning signs for another disease. With collaboration from different specialists, the cause may emerge which is essential to prevent future strokes.
Brain Stem Stroke:
These strokes have complex symptoms and are difficult to diagnose. They usually don’t display the common symptom of weakness on one side of the body but will develop vertigo, dizziness, and imbalance. It can also cause double vision and slurred speech.
The brain stem controls basic activities of the body - from breathing to sleep cycle. All motor control also flows through this area - severe strokes can leave survivors completely paralyzed. If the cause of the stroke in the area is a clot, the issue is time-sensitive. The faster treatment is administered, the significantly lower levels of damage.
Symptoms
Symptoms include trouble understanding and speaking, paralysis or numbness (usually on only one side of the body), trouble seeing with one or both eyes, sudden, severe headache, or lack of coordination.
F.A.S.T:
In order to ensure that people are treated as quickly as possible, there are 3 major symptoms to watch out for. F.A.S.T is a guide for spotting a stroke.
F - Face drooping
A - Arm weakness on one side of the body
S - Speech Difficulty
T - Time to call 911
Treatment
The most common treatment for a stroke is to administer the tissue plasminogen activator. This drug is able to break down clots within your body and thereby restores blood flow to the brain in the case of an ischemic stroke. The treatment needs to administered within 4.5 hours for maximum efficiency. Other emergency treatments include direct medication and stent retriever. Doctors may directly deliver the tPA to the area in your brain where the stroke is occurring via a catheter. This method is known as intra-arterial thrombolysis. The possible treatment window is longer than intravenous tPA, which can be useful in some situations. A stent retriever can be used when attached to a catheter to remove the clot from the cerebral blood vessel. This often used in conjunction with intravenous tPA when the clot is too large to completely dissolve.
For hemorrhagic stroke, doctors will often give drugs or transfusions to counteract the effects of blood thinners if the patient takes them. In addition, they will administer drugs to reduce pressure in the brain, blood vessels, and to prevent seizures. Once the bleeding stops, supportive medical care is administered while the body absorbs the blood or the doctor may perform surgery to alleviate pressure on the brain. In addition, the doctor may recommend a blood vessel repair if an aneurysm or AVM caused your stroke.
There are often complications following a stroke. Many people suffer paralysis usually on one side of the body, lack of control of the throat and mouth muscles making it difficult to talk or swallow. Mentally, patients often find themselves having difficulty thinking or retrieving memories, difficulty controlling their emotions, extreme sensitivity to pain or temperature changes, and changes in behavior or ability to perform common tasks. These effects require individual treatment tailored to each patient’s specific needs and often involve lifestyle changes.
More information
Blog by : Lasya Kambhampati
Comments