Embolic stroke

Related Terms

Aneurysms, angioplasty, arteriography, arteriovenous malformation (AVM), artery, blood clot, carotid, carotid endarterectomy, carotid ultrasonography, cerebrovascular accident (CVA), cholesterol, cocaine, computerized tomography (CT), diabetes, echocardiography, embolus, hemorrhage, hemorrhagic, high blood pressure, hypertension, hypoxia, ischemic, ischemic stroke, magnetic resonance imaging (MRI), methamphetamine, mini-stroke, obesity, oral contraception, oxygen, patent foramen ovale, platelet, stenosis, thrombotic stent, stroke, subarachnoid, thrombus, transient ischemic attack (TIA)

Background

A stroke (or cerebrovascular accident, CVA) is much like what a heart attack is to the heart, but to the brain. A stroke involves the sudden interruption of blood flow and oxygen to areas in the brain and can cause brain damage and loss of function. Stroke develops suddenly, usually in a matter of minutes, and causes symptoms such as paralysis, numbness or weakness often affecting one side of the body, confusion, dizziness, speech problems, and loss of vision. How a stroke patient is affected depends on where the stroke occurs in the brain and how much the brain is damaged.
There are two main types of strokes: ischemic and hemorrhagic. Ischemic strokes are by far the more common type, and occur when a blood clot or plaque (protein, cholesterol, and material) deposit blocks an artery supplying blood to the brain. A hemorrhagic stroke occurs when an artery in the brain bursts, causing blood to flow into the surrounding tissue. The mortality rate is higher for hemorrhagic stroke than for ischemic stroke, with most deaths occurring within the first 48 hours of the event.
A transient ischemic attack (TIA) is a type of stroke that usually lasts only 10 - 20 minutes. TIAs are sometimes considered to be "mini-strokes." While TIAs cause no long-term damage, having a TIA puts an individual at increased risk of acute stroke. Symptoms of TIAs may go unnoticed, and may be confused with other conditions such as epilepsy, migraines, or diabetes.
Stroke is a medical emergency. Prompt treatment of a stroke could be the difference between life and death. Early treatment can also minimize damage to the brain and potential disability.
The National Stroke Association reports that in the United States, stroke is a leading cause of adult disability and the third-leading cause of death. Only heart disease and cancer cause more deaths annually.
Men are 1.25 times more likely to suffer from strokes than women, yet 60% of deaths from stroke occur in women.
Eighty percent of strokes are preventable, which would save approximately 600,000 Americans annually.

Risk factors and causes

Age: A stroke can happen to anyone, but the risk of stroke increases with age. After the age of 55, the risk of stroke doubles for every ten years (decade).
Gender: Stroke is more common in men than women, but more women than men die from stroke. Women tend to be older than men when a stroke occurs and are less likely to recover due to age and fragility. Also, use of hormonal replacement therapy (HRT), birth control pills, and pregnancy can increase the risk of stroke in women.
Race: African American individuals are at an risk of stroke almost double that of Caucasians. Hispanics or Asian/Pacific Islanders also have a higher risk of stroke than Caucasians.
Family history: If a relative in a patient's immediate family, such as a parent or sibling, has had a stroke, a patient's risk of stroke is increased.
Previous stroke or TIA: A prior stroke or a transient ischemic attack (ministroke) increases the chances of another stroke within five years by approximately 25-40%.
High blood pressure (hypertension): High blood pressure is a risk factor for both ischemic and hemorrhagic strokes. It can weaken and damage blood vessels in and around the brain, leaving them vulnerable to atherosclerosis (hardening of the arteries) and hemorrhage. High blood pressure increases stroke risk four to six times, and is the most common cause of stroke
High cholesterol: High cholesterol levels, especially low-density lipoprotein (LDL) cholesterol (the "bad" cholesterol), may increase the risk of atherosclerosis. In excess, LDLs and other materials build up on the lining of artery walls, where they may harden into plaques. The blood must now force it's way through tiny openings, if any opening at all. When the blood flow is completely blocked, a lack of oxygen causes cells to die and may cause a stroke in the brain.
Smoking: Cigarette smoking places an individual at a much higher risk of stroke than nonsmokers. Smoking contributes to plaques in arteries. Nicotine makes the heart work harder by increasing heart rate and blood pressure. The carbon monoxide in cigarette smoke replaces oxygen in the blood (called hypoxia), decreasing the amount of oxygen delivered to the brain and the rest of the body.
Diabetes: Diabetes is a major risk factor for stroke. People with diabetes are at increased risk of stroke because diabetes may damage arteries, predisposing them to atherosclerosis (hardening of the arteries). Overall, the risk of cardiovascular disease (including stroke) is two-and-a-half times higher in men and women with diabetes compared to people without diabetes.
Obesity: A high body mass index (BMI), or the amount of fat on the body, increases the chances of developing high blood pressure, heart disease, atherosclerosis and diabetes, all of which increase risk factors associated with stroke.
Cardiovascular disease: Cardiovascular diseases, or coronary heart disease (CAD), can increase the risk of a stroke. Coronary heart diseases include congestive heart failure, a previous heart attack, an infection of a heart valve (endocarditis), a particular type of abnormal heart rhythm (atrial fibrillation or AF), aortic or mitral valve disease, valve replacement, or a hole in the upper chambers of the heart (patent foramen ovale). AF increases stroke risk up to six times, because the abnormal pumping of the heart allows blood to pool within the chamber and form clots, which are then pumped into the bloodstream and travel throughout the body and potentially into the brain. About 15% of all people who have a stroke have AF. Additionally, atherosclerosis in blood vessels around the heart may indicate atherosclerosis in other blood vessels - including those in and around the brain.
Elevated homocysteine levels: The amino acid homocysteine occurs naturally in the body. Elevated levels of homocysteine have been linked with a high risk of coronary heart disease and stroke. Homocysteine stimulates the growth of cells that help form plaque (deposits of protein and cholesterol) in blood vessels, encouraging blood clotting and blockages in the vessels.
Birth control pills and hormone therapy: The risk of stroke is higher among women who take birth control pills (oral contraception), especially among smokers and those older than 35. Lower dosages may help decrease the risk of stroke. Hormone replacement therapy (HRT) used during menopause also carries an increased risk of stroke.
Sickle cell anemia: Sickle cell anemia, which can cause blood cells to clump up and block blood vessels, also increases stroke risk. Stroke is the second leading killer of people under 20 who suffer from sickle-cell anemia.
Others: Hypercoagulable (increase in blood clotting) conditions such as Factor V Leiden (the most common), prothrombin gene mutation (a hereditary condition), elevated levels of fibrinogen (a protein involved in clotting), deficiencies of natural proteins that prevent clotting (called anticoagulant proteins - such as antithrombin, protein C and protein S), and "sticky" platelets (easily clump together) increase the risk of stroke. Heavy or binge drinking (drinking more than 2 drinks per day may increase stroke risk by 50%), the use of illicit drugs such as cocaine and methamphetamine, some prescription stimulant drugs (amphetamines), and uncontrolled stress can also increase the risk of stroke.

Signs and symptoms

Signs and symptoms of a stroke include sudden numbness or weakness of the face, arm or leg, especially on one side of the body, sudden confusion, trouble speaking or understanding, sudden trouble seeing in one or both eyes, sudden difficulty walking, dizziness, loss of balance or coordination, and sudden, severe headache with no known cause.
For most people, stroke has no warning. One possible indicator of a future stroke is a transient ischemic attack (TIA). A TIA is a temporary interruption of blood flow to some part of the brain. TIA signs and symptoms are similar to stroke, but last for a shorter period of time (usually several minutes to 24 hours), and then disappear with no apparent permanent effects. Individuals who have had a TIA are at a very high risk of having a stroke.

Diagnosis

Physical examination and tests: Risk factors of stroke are evaluated, including high blood pressure, high cholesterol levels, diabetes, medications, elevated levels of homocysteine, and obesity. Stroke symptoms are documented after the occurrence, often using scoring systems such as the National Institutes of Health Stroke Scale, the Cincinnati Stroke Scale, and the Los Angeles Prehospital Stroke Screen. These tests ask medical history questions and measure left and right paralysis (loss of muscle control and movement). The latter is used by emergency medical technicians (EMTs) to determine whether a patient needs transport to a stroke center (a hospital specializing in stroke).
Carotid ultrasonography: This procedure evaluates blood flow using a wand-like device (transducer) that sends high-frequency sound waves into the neck. Narrowing or clotting in the carotid arteries can be determined.
Arteriography: Arteriography views arteries in the brain not normally able to be seen in X-rays. During this procedure, a thin, flexible tube (catheter) is inserted through a small incision, usually in the groin area. The catheter is manipulated through the major arteries and into the carotid or vertebral artery. A dye is then injected through the catheter to provide X-ray images of the arteries.
Computerized tomography angiography (CTA): In computerized tomographic angiography (CTA), a dye is injected into the blood and X-ray beams create a three-dimensional image of the blood vessels in the neck and brain. CTA is used to look for aneurysms (weakened or ruptured blood vessel) or arteriovenous malformations (masses of abnormal blood vessels growing in the brain) and to evaluate arteries for narrowing. CT scanning, which is done without dye, can provide images of the brain and show hemorrhages, but without as much detailed information about the blood vessels.
Magnetic resonance imaging (MRI): An MRI uses a strong magnetic field to generate a three-dimensional view of the brain. This test is sensitive for detecting an area of brain tissue damaged by an ischemic stroke. Magnetic resonance angiography (MRA) uses this magnetic field and a dye injected into the veins to evaluate arteries in the neck and brain.

Complications

A stroke may cause physical or behavioral changes in an individual. Physical changes are dependent on the side and part of the brain affected by the stroke. Stroke may affect the ability to process language, reading, articulation (ability to enunciate words), or even the ability to swallow. Behavioral changes can include depression and other mental illnesses.
Right brain: Different sides of the brain control opposite sides of the body. Therefore, a stroke affecting one side will result in neurological (nervous system or nerve) complications on the side of the body if affects. For example, if the stroke occurs in the brain's right side, the left side of the body will be affected. The symptoms include paralysis on the left side of the body, vision problems, quick, inquisitive behavioral style, and memory loss.
Left brain: If the stroke occurs in the left side of the brain, the right side of the body (and the left side of the face) will be affected, producing effects including paralysis on the right side of the body, speech/language problems, slow, cautious behavioral style, and memory loss.

Treatment

The earlier the treatment is received, the higher the chance of survival and recovery. It is imperative to seek medical attention immediately if a stroke is suspected. Helping identify a stroke victim includes asking the individual to smile, to raise both arms and keep them raised, or to speak a simple sentence (coherently).
Guidelines for stroke prevention have been developed by the American Heart Association. Primary prevention focuses on preventing a stroke, while secondary prevention focuses on preventing stroke in those with a history of stroke or TIA.
Ischemic stroke:
Emergency treatment for an ischemic stroke depends on the location and cause of the clot. Measures are taken to stabilize vital signs, including intravenous (into the veins) fluids and medications such as clot dissolving drugs and anti-platelet drugs.
Tissue plasminogen activator (tPA): If the stroke is diagnosed within three hours of the start of symptoms, a clot-dissolving medication called tissue plasminogen activator (t-PA) is usually given, which may increase the chance of survival and recovery. Tissue plasminogen activator is not safe for hemorrhagic stroke (bleeding in the brain), as use of t-PA would be life-threatening by increasing bleeding.
Anti-platelet drugs: Platelets are cells in the blood that initiate clot formation. Anti-platelet drugs make the platelets less sticky and are therefore less likely to clump (aggregate) and form clots. The most frequently used anti-platelet medication is over the counter aspirin in doses of 81 to 325 milligrams daily. Aggrenox?, a prescription combination product of low-dose aspirin and the anti-platelet agent dipyridamole, may also be used to reduce blood clotting. Other anti-platelet drugs, such as clopidogrel (Plavix?) or ticlopidine (Ticlid?) may also be utilized. The drugs may be used in combination. However, initiation of these therapies are not recommended within 24 hours of treatment with t-PA due to an increase in serious bleeding problems. Side effects include increased risk of bleeding. There are many possible drug and supplement interactions while taking anti-platelet therapy.
Anticoagulants: Anticoagulation treatments slow the time that it takes for the blood to clot. The drugs used in this class include heparin and warfarin (Coumadin?). They affect the mechanism of clotting differently than anti-platelet medications. Heparin, an injection, is a fast acting agent and is used short-term in the hospital, while warfarin, taken by mouth, acts more slowly and is used over a longer term. These drugs have a profound effect on blood clotting and require that the patient work closely with their provider to ensure that they are within therapeutic range as well as to reduce the risk of adverse bleeding events. As with the anti-platelet medications, there are many possible drug and supplement interactions while taking anticoagulant therapy.
Biological therapy: Biologic therapy treats the immune system. The use of abciximab (ReoPro?) in acute stroke is being studied. This injectable drug has anti-platelet activity and must be used within six hours of stroke.
Other medications: Other medications may be given to control blood sugar levels (such as oral blood sugar lowering drugs), fever (including acetaminophen or Tylenol?), and seizures (such as anticonvulsant drugs). In general, high blood pressure is not treated immediately unless systolic pressure is greater than 220 millimeters of mercury (mmHg) and diastolic is more than 120 mmHg (reading as 220/120 mmHg).
Surgical and other procedures: Procedures to open up the artery that has been moderately to severely narrowed by plaque (deposits of cholesterol and protein in the blood) may be necessary. These include carotid endarterectomy and angioplasty.
Carotid endarterectomy: After a stroke has occurred, an incision in the neck is made to expose the carotid artery. The artery is opened and the plaques are removed, thereby reducing the risk of ischemic stroke. However, in addition to the usual risks associated with any surgery, a carotid endarterectomy itself can also trigger a stroke or heart attack by releasing a blood clot or fatty debris in blood vessels in the brain. As a standard practice, surgeons now place filters at strategic points in the bloodstream to "catch" any material that may break free during the procedure, preventing it from traveling to the heart or brain.
Angioplasty: Angioplasty widens the inside of an artery leading to the brain (usually the carotid artery). During this procedure, a balloon-tipped catheter is maneuvered into the obstructed area of the suspected artery. The balloon is inflated, compressing the plaques against the artery walls. A metallic mesh tube (stent) is usually left inside the artery following the procedure to prevent recurrent narrowing. Stents can stay in for many years, but occasionally must be replaced. Anticoagulant drugs such as aspirin and/or clopidogrel (Plavix?) are commonly used after stent placement.
Hemorrhagic stroke:
Surgery may be used to treat a hemorrhagic stroke or prevent recurrence. The most common procedures include aneurysm (weakened or ruptured blood vessel) clipping and arteriovenous malformation (AVM) (masses of abnormal blood vessels growing in the brain) removal, and both surgeries carry high risks such as an increase in bleeding and damage to the brain, causing long-term complications such as paralysis (loss of muscle control and use) and behavioral changes.
Surgical AVM removal: Surgical removal of a smaller AVM from a more accessible portion of the brain can eliminate the risk of rupture, lowering the overall risk of hemorrhagic stroke. Other treatment options for AVMs include radiation or embolization, in which the small arteries supplying the blood to the AVM are blocked with clamps, shrinking the AVM and reducing the chances of rupture.
Aneurysm clipping: A tiny clamp is placed at the base of the aneurysm, isolating it from the circulation of the artery. The clamp is attached to the vessels to keep it from bursting (rupturing) or bleeding.
Coiling: During coil embolization, tiny, soft platinum coils are placed within a bulging brain aneurysm in order to relieve pressure from circulating blood on the walls of the aneurysm and to prevent rupture. The coils are guided to the aneurysm through the use of a catheter inserted into the femoral artery at the groin. Through the use of precision radiologic monitors, and 3D imaging, the coils are advanced to the aneurysm.
Recovery and rehabilitation: Stroke rehabilitation (for both ischemic and hemorrhagic stroke) is the process by which patients with stroke-induced disabilities undergo treatment to help them regain and relearn the skills necessary for everyday living. It also aims to help the survivor understand and adapt to difficulties such as speech and movement, prevent secondary complications, and educate family members to play a supporting role. Following a stroke, the period of recovery and rehabilitation necessary varies between patients depending on the area of the brain involved and the amount of tissue damaged. Harm to the right side of the brain may impair movement and sensation on the left side of the body. Damage to brain tissue on the left side may affect movement on the right side; this damage may also cause speech and language disorders. In addition, individuals who have experienced a stroke may experience problems with breathing, swallowing, balancing and hearing, and loss of vision, bladder or bowel function. Recovery may take years. Some may recover in full, while others may not progress at all. This depends on each individual and the extent of the stroke damage.

Integrative therapies

Unclear or conflicting scientific evidence:
Acupressure, shiatsu, tuina: There is promising early data supporting the use of acupressure as an adjunct treatment in the recovery from poststroke paralysis. Future research is required before any recommendation can be made regarding the use of this therapy for stroke.
With proper training, acupressure appears to be safe if self-administered or administered by an experienced therapist. Serious long-term complications have not been reported, according to scientific data. Hand nerve injury and herpes zoster ("shingles") cases have been reported after shiatsu massage. Forceful acupressure may cause bruising.
Acupuncture: The practice of acupuncture, or the insertion of needles into the body to move energy or "chi" in a particular area, originated in China 5,000 years ago. Acupuncture has been used traditionally in China for treatment of stroke complications such as paralysis (loss of muscle control and use). Several studies have been conducted on use of acupuncture for acute cerebral infarction and stroke recovery. More research is needed to determine the effectiveness of acupuncture for this application.
Needles must be sterile in order to avoid disease transmission. Avoid with valvular heart disease, medical conditions of unknown origins, or infections. Acupuncture should not be applied to the chest in patients with lung diseases or on any area that may rely on muscle tone to provide stability. Avoid use in infants, young children, or in patients with needle phobias. Use cautiously with bleeding disorders, neurological disorders, seizure disorders, or diabetes. Use cautiously in elderly or medically compromised patients. Use cautiously in patients who will drive or operate heavy machinery after acupuncture. Use cautiously if taking anticoagulants. Avoid if pregnant.
Aortic acid: Aortic extract is derived from the hearts of animals, usually sheep, cows, or pigs. There are many substances included in aortic acid. Mesoglycan, a preparation of glycosaminoglycans, is the most studied of these constituents. Mesoglycan has shown activity in anticoagulation (blood thinning) and increasing blood vessel health. Preliminary randomized, controlled studies also indicate that it may be helpful in reducing recurring ischemic cerebral attacks (stroke) and improving quality of life. However, some non-subjective tests do not show any benefit by mesoglycan. High-quality studies are needed to better determine the effectiveness of mesoglycan for cerebral ischemia.
Allergic reactions have not been reported in the available literature. Due to the heparan sulfate content of mesoglycan, patients with an allergy to heparin or heparinoid derivatives should use caution. Use cautiously with coagulation (blood) disorders or taking anticoagulation therapy. Use cautiously with hypertension (high blood pressure) or if taking antihypertension drugs. Avoid if pregnant or breastfeeding.
Arnica: Arnica (Arnica montana) is a widely used herbal supplement. It is also available as a homeopathic drug approved by the U.S. Food and Drug Administration (FDA). Homeopathic drugs are very dilute substances and have no apparent side effects or adverse reactions. Homeopathic arnica has been used in stroke recovery. More research is needed.
Avoid if allergic or hypersensitive to arnica or any member of the Asteraceae or Compositae families (sunflowers, marigolds or any related plants like daisies, ragweed, or asters). Use cautiously with blood thinners, protein-bound drugs, cholesterol or heart medications, or diabetes drugs. Use cautiously with a history of stroke. Avoid contact with open wounds or near the eyes and mouth. Avoid if pregnant or breastfeeding.
Aromatherapy: There is currently not enough scientific evidence to recommend for or against the use of aromatherapy in patients for stroke recovery. Additional research is needed to make a conclusion.
Essential oils should be administered in a carrier oil to avoid toxicity. Avoid with history of allergic dermatitis. Use cautiously if driving/operating heavy machinery. Avoid consuming essential oils. Avoid direct contact of undiluted oils with mucous membranes. Use cautiously if pregnant.
Betel nut: Several poor-quality studies report the use of betel nut (Areca catechu) taken by mouth for stroke recovery. In light of the potential toxicities of betel nut, additional evidence is needed in this area. Constituents of areca may be potentially carcinogenic. Long-term use has been associated with oral submucous fibrosis (OSF), as well as the formation of pre-cancerous oral lesions and squamous cell carcinoma. Acute effects of betel chewing include worsening of asthma, low blood pressure, and rapid heart beat.
Betel nut cannot be considered safe for human use by mouth. This is due to toxic effects associated with short or long-term chewing or eating of betel nut. Avoid if allergic to betel nut or other plants of the Palmaceae family. Avoid if pregnant or breastfeeding.
Black pepper: Nasal inhalation of volatile black pepper oil may improve swallowing dysfunction symptoms during stroke recovery. However, more research is needed in this area.
Avoid if allergic or hypersensitive to black pepper (Piper nigrum), its constituents, or members of the Piperaceae family. Use cautiously if taking anti-asthmatic drugs, cholinergic agonists, cyclosporine A or digoxin, cytochrome P450 metabolized agents, oral herbs or drugs, phenytoin, propranolol, rifamipicin (rifampin), or theophylline. Use cautiously with gastrointestinal disorders. Avoid if pregnant or breastfeeding.
Choline: Choline is an essential nutrient related to the water-soluble B-complex vitamins. The largest dietary source of choline is egg yolk. Though many studies have found promising results, others have not shown statistical significance when assessing choline for the treatment of acute ischemic stroke. Further well-designed trials are needed. Choline supplements are not recommended during pregnancy or breastfeeding unless otherwise advised by a doctor.
Danshen: Danshen (Salvia miltiorrhiza) is widely used in traditional Chinese medicine (TCM), often in combination with other herbs. Due to poor quality of evidence, unclear safety, and the existence of more proven treatments for ischemic stroke, this use of danshen cannot be recommended for this indication.
Avoid if allergic or hypersensitive to danshen. Use cautiously if taking sedatives, hypolipidemics, cardiac glycosides, CYP-metabolized agents, nitrate ester, steroidal agents, or some anti-inflammatories (e.g. ibuprofen). Use cautiously with altered immune states, arrhythmia, compromised liver function, or with a history of glaucoma, stroke, or ulcers. Stop use two weeks before and immediately after surgery/dental/diagnostic procedures with bleeding risks. Use cautiously if driving or operating heavy machinery. Avoid if taking blood thinners (anticoagulants), digoxin, or hypotensives, including ACE inhibitors (e.g. captopri), or Sophora subprostrata root or herba serissae. Avoid use after cerebral ischemia. Avoid if pregnant or breastfeeding.
Focusing: Focusing strategies may help restore motor function during stroke recovery. More evidence is needed in this area. Further research may also determine which focusing strategies are most effective to use during stroke recovery.
Side effect reporting is rare, but patients should consult with a qualified healthcare practitioner before making decisions about medical conditions and practices. Individuals with severe emotional difficulties should not abandon proven medical and psychological therapies but rather choose focusing as a possible adjunct.
Folate: Folic acid and folate are forms of a water-soluble B vitamin. Folate occurs naturally in food and folic acid is the synthetic form of this vitamin. Study results are mixed for the use of folate in stroke patients. Further research is needed before a recommendation can be made.
Avoid if allergic or hypersensitive to folate or any folate product ingredients. Use cautiously if receiving coronary stents and with anemia and seizure disorders. It is recommended that pregnant women consume 400 micrograms daily in order to reduce the risk of fetal defects. Folate is likely safe if breastfeeding.
Ginkgo: Ginkgo (Ginkgo biloba) has been used medicinally for thousands of years. Today, it is one of the top selling herbs in the United States. Laboratory studies suggest that ginkgo may be helpful immediately following strokes because of possible antioxidant or blood vessel effects. However, initial study of ginkgo in people having strokes found no benefits, and ginkgo has been reported to increase intracranial bleeding. Further research is needed to better determine the effectiveness of ginkgo for acute ischemic stroke.
Caution is advised when taking ginkgo supplements, as numerous adverse effects including subarachnoid hemorrhage and drug interactions are possible. Ginkgo supplements are not recommended during pregnancy or breastfeeding, unless otherwise advised by a doctor.
Jasmine: Limited population study found that tea drinking may decrease risk of stroke; however, use of jasmine tea had less of an effect than black or green teas. This indicates that the reduction of stroke risk may not be related to jasmine. Additional study using jasmine alone is needed to make a conclusion.
Use cautiously during pregnancy or lactation. Avoid in patients allergic to jasmine, jasmine oil, or other fragrances. Avoid oral use of jasmine essential oils.
L-carnitine: L-carnitine, or acetyl-L-carnitine, is an amino acid that occurs naturally in the body. L-carnitine is obtained from foods such as meat and dairy products. There are a limited number of studies showing a positive effect of L-carnitine on cerebral blood flow and metabolism of the brain in patients who have suffered from cerebral ischemia. Additional study is required.
Avoid with known allergy or hypersensitivity to carnitine. Use cautiously with peripheral vascular disease, hypertension (high blood pressure), alcohol-induced liver cirrhosis, or diabetes. Use cautiously in low birth weight infants and individuals on hemodialysis. Use cautiously if taking anticoagulants (blood thinners), beta-blockers, or calcium channel blockers. Avoid if pregnant or breastfeeding.
Melatonin: The natural hormone melatonin aids in the regulation of sleep/wake cycles (circadian rhythm). Theories suggest that the antioxidant properties of melatonin may reduce the amount of neurologic damage patients experience after stroke. In addition, melatonin levels may be decreased in people immediately after stroke, and it has thus been suggested that melatonin supplementation may be beneficial, although this has not been shown in humans. Animal study found that melatonin supplementation decreased the brain tissue damage caused by stroke. At this time, the effects of melatonin supplements given immediately after stroke are not clear.
Caution is advised when taking melatonin supplements, as numerous adverse effects including drug interactions are possible. Melatonin is not recommended during pregnancy or breastfeeding, unless otherwise advised by a doctor. Healthcare professionals recommend using melatonin for more than four to six weeks.
Moxibustion: Moxibustion is a healing technique employed across the diverse traditions of acupuncture and oriental medicine for over 2,000 years. Moxibustion uses the principle of heat to stimulate circulation and break up congestion or stagnation of blood and chi. Moxibustion is more closely related to acupuncture as it is applied to specific acupuncture points. Limited available study suggests that electro-acupuncture may reduce spasticity in patients who have experienced stroke, but evidence is lacking that moxibustion offered any additive benefit. More studies are needed to determine whether or not moxibustion may contribute to recovery from stroke.
Avoid with aneurysms, any kind of "heat syndrome," heart disease, convulsions, cramps, diabetic neuropathy, extreme fatigue, anemia, fever, or inflammatory conditions. Avoid over allergic skin conditions, ulcerated sores, skin adhesions, or inflamed areas or organs. Do not use over the face, genitals, head, or nipples. Use cautiously over large blood vessels and thin or weak skin. It is considered not advisable to bathe or shower for up to 24 hours after a moxibustion treatment. Avoid if pregnant or breastfeeding.
Omega-3 fatty acids: Omega-3 fatty acids are essential fatty acids found in some plants and fish. Several large epidemiological studies have examined the effects of omega-3 fatty acid intake on stroke risk. Some studies suggest benefits for stroke prevention, while others do not. Effects are likely on ischemic (lack of blood flow) or thrombotic (blood clots) stroke risk, and very large intakes of omega-3 fatty acids may actually increase the risk of hemorrhagic (bleeding) stroke. At this time, it is unclear if there are benefits in people with or without a history of stroke, or if effects of fish oil are comparable to other treatment strategies.
Avoid if allergic or hypersensitive to fish, omega-3 fatty acid products that come from fish, nuts, linolenic acid, or omega-3 fatty acid products that come from nuts. Avoid during active bleeding. Use cautiously with bleeding disorders, diabetes, low blood pressure or drugs, herbs or supplements that treat any such conditions. Use cautiously before surgery.
Peppermint: Peppermint (Mentha piperita) is a flowering plant that grows throughout Europe and North America. Aromatherapy with peppermint oil, lavender, and rosemary has been used to reduce shoulder pain and improve motor power during stroke recovery. Although treatment appeared to have beneficial effects, it is unclear if this was caused by peppermint oil or the other two herbs. Additional studies using peppermint oil alone are needed.
Avoid if allergic or hypersensitive to peppermint or menthol. Peppermint is generally considered safe in non-allergic adults when taken in small doses. Use cautiously with G6PD deficiency or gallbladder disease. Menthol, which makes up part of peppermint oil, is generally considered safe in non-allergic adults. However, doses of menthol greater than 1 gram per kilogram of body weight may be deadly in humans. Avoid if pregnant or breastfeeding.
Physical therapy: Physical therapy was first documented in China around 3000 BC with the use of joint manipulation and massage to relieve pain. Physical therapy is a popular choice for patients undergoing stroke rehabilitation. It aims to strengthen weakened muscle groups through repetitive motion, increase overall function including cognitive function, and improve gait and walking. Available studies have used a variety of exercises, which makes it nearly impossible to compare the evidence. Furthermore, physical therapy is often used as a control group in these studies. Higher quality studies are needed.
Not all physical therapy programs are suited for everyone, and patients should discuss their medical history with their qualified healthcare professionals before beginning any treatments. Based on the available literature, physical therapy appears generally safe when practiced by a qualified physical therapist; however, complications are possible. Persistent pain and fractures of unknown origin have been reported. Physical therapy may increase the duration of pain or cause limitation of motion. Pain and anxiety may occur during the rehabilitation of patients with burns. Both morning stiffness and bone erosion have been reported in the literature, although causality is unclear. Erectile dysfunction has also been reported. All therapies during pregnancy and breastfeeding should be discussed with a licensed obstetrician/gynecologist before initiation.
Psychotherapy: Psychotherapy is an interactive process between a person and a qualified mental health professional (psychiatrist, psychologist, clinical social worker, licensed counselor, or other trained practitioner). Its purpose is the exploration of thoughts, feelings and behavior for the purpose problem solving or achieving higher levels of functioning. Studies show mixed results about the efficacy of cognitive behavioral psychotherapy for depression following stroke. More research is needed.
Psychotherapy is not always sufficient to resolve mental or emotional conditions. Psychiatric medication is sometimes needed. The reluctance to seek and use appropriate medication may contribute to worsening of symptoms or increased risk for poor outcomes. In order to be successful, psychotherapy requires considerable personal motivation and investment in the process. This includes consistent attendance and attention to treatment recommendations provided by the practitioner. Not all therapists are sufficiently qualified to work with all problems. The client or patient should seek referrals from trusted sources and should also inquire of the practitioner's training and background before committing to work with a particular therapist. Some forms of psychotherapy evoke strong emotional feelings and expression. This can be disturbing for people with serious mental illness or some medical conditions. Psychotherapy may help with post-partum depression, but is not a substitute for medication, which may be needed in severe cases.
Reiki: Reiki is a Buddhist practice that is approximately 2,500 years old. It is used for stress reduction and relaxation and is administered by "laying on hands" and moving around the "energy" of the body. In available study, Reiki did not have any clinically useful effect on stroke recovery in patients receiving appropriate rehabilitation therapy. Selective positive effects on mood and energy were noted.
Reiki is not recommended as the sole treatment approach for potentially serious medical conditions, and should not delay the time it takes to consult with a healthcare professional or receive established therapies. Use cautiously with psychiatric illnesses.
Relaxation therapy: Relaxation techniques include behavioral therapeutic approaches that differ widely in philosophy, methodology, and practice. The primary goal is usually non-directed relaxation. Most techniques share the components of repetitive focus (on a word, sound, prayer phrase, body sensation, or muscular activity), adoption of a passive attitude towards intruding thoughts, and return to the focus. Research suggests that relaxation techniques may help stroke victims with facial paralysis recover more rapidly. Better research is necessary before a firm conclusion can be drawn.
Avoid with psychiatric disorders like schizophrenia/psychosis. Jacobson relaxation (flexing specific muscles, holding that position, then relaxing the muscles) should be used cautiously with illnesses like heart disease, high blood pressure, or musculoskeletal injury. Relaxation therapy is not recommended as the sole treatment approach for potentially serious medical conditions, and should not delay the time to diagnosis or treatment with more proven techniques.
Tai chi: Tai chi is a system of movements and positions believed to have developed in 12th Century China. Tai chi techniques aim to address the body and mind as an interconnected system and are traditionally believed to have mental and physical health benefits to improve posture, balance, flexibility, and strength. Tai chi may benefit social and general functioning in stroke recovery patients but may not be as effective as physiotherapy for balance and speed of walking.
Avoid with severe osteoporosis or joint problems, acute back pain, sprains, or fractures. Avoid during active infections, right after a meal, or when very tired. Some believe that visualization of energy flow below the waist during menstruation may increase menstrual bleeding. Straining downwards or holding low postures should be avoided during pregnancy, and by people with inguinal hernias. Some tai chi practitioners believe that practicing for too long or using too much intention may direct the flow of chi (qi) inappropriately, possibly resulting in physical or emotional illness. Tai chi should not be used as a substitute for more proven therapies for potentially serious conditions. Advancing too quickly while studying tai chi may increase the risk of injury.
Transcutaneous electrical nerve stimulation (TENS): TENS is a non-invasive technique in which a low-voltage electrical current is delivered through wires from a small power unit to electrodes located on the skin. Studies of TENS for post-stroke rehabilitation report inconsistent findings, and benefits have not consistently been demonstrated. Additional research is necessary before a clear conclusion can be reached.
Avoid with implantable devices, such as defibrillators, pacemakers, intravenous infusion pumps, or hepatic artery infusion pumps. Use cautiously with decreased sensation (such as neuropathy) or with seizure disorders. Avoid if pregnant or breastfeeding due to lack of safety evidence.
Vitamin C (ascorbic acid): There are variable results of studies that have measured the association of vitamin C intake and risk of stroke. Some studies have reported no benefits, while other research reports that daily low-dose vitamin C may reduce the risk of death from stroke. Additional research is necessary to better understand the role of Vitamin C in stroke prevention.
Avoid if allergic or sensitive to vitamin C product ingredients. Vitamin C is generally considered safe in amounts found in foods. Vitamin C supplements are also generally considered safe in most individuals if taken in recommended doses. Avoid high doses of vitamin C with glucose 6-phosphate dehydrogenase deficiency, kidney disorders or stones, cirrhosis (inflammation of the liver), gout, or paroxysmal nocturnal hemoglobinuria (bleeding disorder). Vitamin C intake from food is generally considered safe if pregnant or breastfeeding.
Yoga: Yoga is an ancient system of relaxation, exercise, and healing with origins in Indian philosophy. Preliminary study suggests possible benefits of a yoga-based exercise program on people who have had a stroke and have impaired health status and reduced level of activity. Although results seem promising, further well-designed research is needed to confirm these findings.
Yoga is generally considered to be safe in healthy individuals when practiced appropriately. Avoid some inverted poses with disc disease of the spine, fragile or atherosclerotic neck arteries, risk for blood clots, extremely high or low blood pressure, glaucoma, detachment of the retina, ear problems, severe osteoporosis, or cervical spondylitis. Certain yoga breathing techniques should be avoided in people with heart or lung disease. Use cautiously with a history of psychotic disorders. Yoga techniques are believed to be safe during pregnancy and breastfeeding when practiced under the guidance of expert instruction (the popular Lamaze techniques are based on yogic breathing). However, poses that put pressure on the uterus, such as abdominal twists, should be avoided in pregnancy.
Fair negative scientific evidence:
Beta-carotene: Taking all-trans beta-carotene (synthetic beta-carotene) orally has been reported to have no effect on the overall incidence of stroke in male smokers. Additionally, there is some evidence that beta-carotene actually increases the risk of intracerebral hemorrhage by 62% in patients who also drink alcohol.
Avoid if sensitive to beta-carotene, vitamin A or any other ingredients in beta-carotene products.
Vitamin B12: Vitamin B12 is a water-soluble vitamin commonly found in many foods, including fish, shellfish, meats, and dairy products. In people with a history of stroke, neither high-dose vitamin B12 combinations containing pyridoxine, vitamin B12, and folic acid nor low-dose combinations containing pyridoxine, vitamin B12, and folic acid seem to affect risk of recurring stroke.
Vitamin B12 is generally considered safe when taken in amounts that do not exceed the recommended dietary allowance (RDA). Avoid vitamin B12 supplements if allergic to cobalamin, cobalt, or any other vitamin B12 product ingredients. Avoid with coronary stents or Leber's disease. Use cautiously if undergoing angioplasty.
Vitamin B6: Pyridoxine alone or in combination with B12 and folic acid orally does not seem to be useful for preventing stroke reoccurrence.
Avoid vitamin B6 products if sensitive or allergic to any of their ingredients. Some individuals seem to be particularly sensitive to vitamin B6 and may have problems at lower doses. Vitamin B6 is likely safe when used orally in doses not exceeding the recommended dietary allowance (RDA). Use cautiously if pregnant or breastfeeding.
Vitamin E: Recent evidence from the Women's Health Study suggests that regular vitamin E supplementation daily does not reduce the risk of stroke. At this time, based on the best available scientific evidence and recent safety concerns, vitamin E cannot be recommended for this use.
Caution is advised when taking vitamin E supplements, as adverse effects including an increase in bleeding and drug interactions are possible. Vitamin E supplements should not be used if pregnant or breastfeeding, unless otherwise directed by a doctor.

Author information

This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Bibliography

American Stroke Association. .
National Institutes of Health. .
National Institute of Neurological Disorders and Stroke. .
National Stroke Association. .
Natural Standard: The Authority on Integrative Medicine. .
Society for Interventional Radiology. .

Types of stroke

Ischemic stroke: About 80% of strokes are ischemic strokes. Blood clots or other particles such as cholesterol may block arteries to the brain and cause severely reduced blood flow (ischemia). This deprives the brain cells of necessary oxygen and nutrients, and may lead to cell death within minutes. The most common ischemic strokes include thrombotic stroke and embolic stroke.
Thrombotic stroke: This type of stroke occurs when a blood clot (thrombus) forms in one of the arteries that supply blood to the brain. Areas damaged by atherosclerosis (hardening of the arteries) are highly susceptible to developing a blood clot. Arteries in the brain or in the neck (carotid arteries) that carry blood to the brain are susceptible. An ischemic stroke may also be caused by plaque (deposits of fat, protein, and other particles in the blood) that narrows or completely clogs an artery. This narrowing is called stenosis.
Embolic stroke: An embolic stroke occurs when a blood clot or other particle forms in a blood vessel away from the brain (such as the heart) and travels through the blood to eventually lodge in narrower brain arteries (called an embolus). Emboli may often be caused by irregular beating in the heart's two upper chambers (atrial fibrillation). This abnormal heart rhythm can lead to stagnant (sluggish) blood flow and the formation of blood clots.
Hemorrhagic stroke: Hemorrhage means bleeding. Hemorrhagic stroke occurs when a blood vessel in the brain leaks or breaks open (ruptures). Hemorrhages can result from a number of conditions that affect the blood vessels, including uncontrolled high blood pressure (hypertension) and weak spots in the blood vessel walls (aneurysms). A less common cause of hemorrhage is the rupture of an arteriovenous malformation (AVM), or a malformed tangle of thin-walled blood vessels present at birth. There are two types of hemorrhagic stroke including intracerebral hemorrhage and subarachnoid hemorrhage.
Intracerebral hemorrhage: In this type of stroke, a blood vessel in the brain bursts and spills into the surrounding brain tissue, damaging cells. Brain cells beyond the leak are deprived of oxygen and are also damaged. High blood pressure is the most common cause of this type of hemorrhagic stroke, causing small arteries inside the brain to become fragile and susceptible to tearing and rupture.
Subarachnoid hemorrhage: In this type of stroke, bleeding starts in a large artery on or near the membrane surrounding the brain and spills into the space between the surface of the brain and skull. A subarachnoid hemorrhage is often signaled by a sudden, severe "thunderclap" headache. This type of stroke is commonly caused by the rupture of an aneurysm, which can develop with age or result from a genetic predisposition. After a subarachnoid hemorrhage, vessels may go into vasospasm, in which arteries near the hemorrhage widen and narrow erratically, causing brain cell damage by further restricting or blocking blood flow to portions of the brain.

Lifestyle changes and prevention

Guidelines for stroke prevention have been developed by the American Heart Association. Primary prevention focuses on preventing a stroke, while secondary prevention focuses on preventing stroke in those with a history of stroke or TIA.
High blood pressure (hypertension) control: One of the most important interventions that can be made in prevention of strokes is the reduction of high blood pressure. Lowering a patient's blood pressure can help prevent a subsequent transient ischemic attack or stroke. Exercising, managing stress, maintaining a healthy weight, and limiting sodium and alcohol intake are all ways to keep hypertension in check. Medications to treat hypertension, such as diuretics, angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers may also be utilized.
Cholesterol and saturated fat intake reduction: Eating less cholesterol and fat, especially saturated fat, may help prevent further buildup of plaque in the arteries. Medications from the "statin" drug-class, which work by inhibiting an enzyme (HMG-CoA reductase) that is used to make cholesterol in the body may be prescribed to help reduce unhealthy cholesterol levels.
Smoking cessation: Quitting smoking reduces the risk of stroke. Smoking can double or triple the chances of having a stroke.
Diabetes control: Managing diabetes with diet, exercise, weight control and medication is essential. Strict control of blood sugar may reduce damage to the brain in the case of a stroke. Increases in blood sugar levels can damage fragile blood vessels in the body, including the brain, and increase the risk of rupture (breaking open).
Weight control: Being overweight contributes to other risk factors for stroke, such as high blood pressure, cardiovascular disease and diabetes. Weight loss of as little as 10 pounds may lower blood pressure and improve cholesterol levels.
Exercise: Exercise can lower blood pressure, increase the level of HDL cholesterol (good cholesterol), and improve the overall health of blood vessels and heart. It also helps control weight, control diabetes and reduce stress. Thirty minutes daily of exercise is normally recommended, but each individual should develop an exercise program for his/her own physical ability. A study reported that men with the highest degree of physical fitness were more than three times less likely than men with the lowest degree of physical fitness to have a stroke.
Stress management: Stress can cause an increase in blood pressure along with increasing the blood's tendency to clot. Finding ways to decrease stress is important in preventing stroke, especially if an individual has other risk factors.
Alcohol drinking: Alcohol can be both a risk factor and a preventive measure for stroke. Binge drinking and heavy alcohol consumption increase the risk of high blood pressure and of ischemic and hemorrhagic strokes. However, drinking small to moderate amounts of alcohol (1-2 drinks a day) can increase HDL cholesterol and decrease the blood's clotting tendency. Both factors can contribute to a reduced risk of ischemic stroke.
Illicit drugs elimination: Street drugs, such as methamphetamine (crystal meth, ice), cocaine, and ecstasy are established risk factors for a transient ischemic attack (TIA) or a stroke.
Dietary modification: Eat healthy foods. A healthy diet should include five or more daily servings of fruits and vegetables, foods rich in soluble fiber (such as oatmeal and beans), foods rich in calcium (dairy products, spinach), soy products (such as tempeh, miso, tofu and soy milk), and foods rich in omega-3 fatty acids, including cold-water fish, such as salmon, mackerel and tuna. Pregnant women and women who plan to become pregnant in the next several years should limit their weekly intake of cold-water fish because of the potential for mercury contamination, which can cause fetal damage.