A "mini-stroke" or "transient ischemic attack" (TIA) occurs when there is a temporary drop in the blood supply to the brain.
Various events or conditions can cause the brain to be deprived of oxygen. Symptoms of a transient ischemic attack (TIA) are similar to those of a stroke, but they do not last as long.
It is estimated that up to 500,000 people in the United States experience a TIA each year.
Because symptoms fade away rapidly, most patients do not seek medical help. However, between
Rapid evaluation and treatment of people who experienced a mini-stroke, either in specially designed TIA clinics or the emergency room, can significantly reduce the risk of a subsequent stroke.
Fast facts on TIA
- A mini-stroke occurs when blood is temporarily cut off to regions of the brain.
- Around 500,000 Americans have a stroke each year.
- Rapid care is essential to minimize the medical implications of a stroke.
- The object of TIA treatment is to prevent further occurrences.
- One of the most common drugs used to prevent TIAs is warfarin, an anticoagulant medication.
A transient ischemic attack (TIA) is like a stroke in that it produces similar symptoms, but it only lasts a few minutes and causes no permanent damage. It is sometimes called a mini-stroke.
It happens when there is not enough oxygen reaching the brain. This is often due to a blood clot that remains for a short while.
When the clot breaks up or moves on, symptoms subside.
The American Stroke Association (ASA) urges people not to ignore a TIA, as it can be a warning of a future, full-blown stroke.
People with TIA experience varying symptoms, depending on which part of the brain is affected.
The signs and symptoms of a TIA are represented by the acronym FAST (Face, Arms, Speech, Time):
- Face: The face may fall on one side as some of the facial muscles become paralyzed. The person's eye or mouth may droop, and they may be unable to smile properly.
- Arms: Arm weakness or numbness might make it hard for the individual to either raise both arms or to keep them raised.
- Speech: Speech may be slurred and garbled.
- Time: If just one of these symptoms are present, it is time to dial emergency services.
Being able to identify the signs and symptoms present in FAST is especially important if you live with somebody in a high-risk group, such as an older adult, or an individual with high blood pressure or diabetes. FAST is also a reminder that the sooner medical treatment is sought, the better the chance of recovery.
Other signs and symptoms of a TIA can include:
- difficulty talking
- difficulty understanding what others are talking about
- problems swallowing
- very bad headache
- paralysis, numbness, or weakness on one side of the body
- in severe cases loss of consciousness
If anybody experiences any of these signs and symptoms themselves or witnesses anybody else experiencing them, medical attention should be sought immediately. TIA symptoms are temporary and should disappear within 24 hours. They may last from 2-15 minutes.
Which conditions can mimic a TIA?
Recognizing a TIA can be complicated, especially as other conditions can produce similar symptoms and bodily effects.
- low blood sugar
- minor seizures
The way to rule out these other conditions is that a TIA will often heavily impact one part of the body, such as sensation and movement in a single limb or vision. This is due to a TIA's effect in blocking a single blood vessel. Conditions that mimic a TIA will generally cause bodywide neurological symptoms, such as tingling or fainting.
To prevent TIA developing into a full-blown stroke, it is vital to have any symptoms checked that could suggest the presence of a TIA.
A TIA happens when the supply of oxygen to the brain is disrupted.
Disruption of blood supply
Two main blood vessels called the carotid arteries supply blood to the brain. These arteries branch off into many smaller blood vessels. A TIA can occur if one of the smaller blood vessels becomes blocked, depriving that part of the brain of oxygen-rich blood.
Atherosclerosis causes arteries to narrow. Fatty deposits develop on the inner lining of blood vessels, causing them to become hardened, thickened, and less flexible. This makes it much more difficult for the blood to flow around the body.
A blood clot can disrupt the supply of oxygen-rich blood to parts of the brain. Blood clots are usually caused by:
- Heart conditions, such as congestive heart muscle disease or atrial fibrillation.
- Blood conditions, including leukemia (blood cell cancer) and sickle cell anemia.
An embolism is a blood clot from one part of the body that becomes dislodged and travels into one of the arteries that supplies the brain. An embolism can cause a TIA.
Hemorrhage (internal bleeding)
A minor brain hemorrhage (small amount of bleeding in the brain) can cause a TIA; however, this is rare.
There are some risk factors for TIA that can be changed, and others that cannot.
Risk factors that cannot be changed:
- Family history: People with a close relative who has had a stroke or TIA.
- Age: People aged over 55 have a higher risk of having a TIA.
- Sex: Males are at slightly greater risk.
- Ethnic origin: People of black African ancestry have a higher risk.
Risk factors that can be changed:
- Hypertension, or high blood pressure.
- Cardiovascular disease: People with cardiovascular diseases are at greater risk of having a TIA. This includes a heart defect, heart failure, or arrhythmia (abnormal heart rhythm).
- Carotid artery disease: This develops when blood vessels in the neck leading to the brain are clogged.
- PAD (peripheral artery disease): When blood vessels that carry blood to the arms and legs become clogged.
- Smoking: People who smoke increase their risk of developing various diseases and conditions, including TIA and stroke.
- Sedentary lifestyle: People who are physically inactive have a significantly higher risk.
- Diabetes: People with diabetes are more likely to suffer from atherosclerosis (narrowing of the arteries due to a buildup of fatty deposits).
- Bad diet: Individuals who consume too much bad quality fat and or salt have a higher risk of stroke and TIA.
- Blood cholesterol levels: If blood cholesterol levels are high, it increases the risk of TIA or stroke.
- Homocysteine levels: Homocysteine is an amino acid produced by the body as a byproduct of consuming meat. Elevated levels of homocysteine in the blood can make the arteries thicken and scar; they are more susceptible to clogs.
- Bodyweight: Obese people have a significantly higher risk of having a TIA or stroke.
- Alcohol: People who drink large quantities of alcohol regularly are also at higher risk.
- Illegal drugs: Some illegal drugs, such as cocaine, can raise the risk of stroke or TIA if taken often enough.
Treatment will depend on the cause of the TIA. The doctor may prescribe medication that lowers the risk of a blood clot, or recommend surgery or an angioplasty.
The type of medication prescribed will depend on what caused the TIA, how severe it was, and what part of the brain was affected.
Anti-platelet drugs: These make platelets in the blood less likely to stick together and form a clot that can block blood flow. Anti-platelet drugs include:
Aspirin and dipyridamole: Some doctors may prescribe Aggrenox, which contains both aspirin and dipyridamole. Some doctors may recommend ticlopidine (Ticlid).
Side effects of aspirin can include:
- ringing in the ears
- stomach irritation and bleeding
Side effects of dipyridamole may include:
Clopidogrel: If a person has experienced severe side effects from taking aspirin, had a further TIA despite taking aspirin, or has arterial disease, the doctor may prescribe clopidogrel (Plavix).
Side effects of clopidogrel may include:
- abdominal pain
Anticoagulants: Anti-coagulants interfere with many other medications, other over-the-counter drugs, and herbs. Always talk to your doctor before taking any other medication or herbs when on anticoagulants.
Warfarin (Coumadin) and heparin: Warfarin can be used long-term, while heparin is used short-term.