What is a TIA?

TIA stands for Transient Ischemic Attack. Another name for a TIA is "mini-stroke". A TIA occurs when blood flow to the brain is temporarily interrupted. A TIA has the same symptoms of a stroke, the only difference being that symptoms from a TIA improve quickly, while symptoms from a stroke do not.

How do you know if someone is having a TIA?

Common symptoms associated with a TIA include:

• numbness or weakness on one side of the body
• trouble speaking, such as slurring of speech or loss of ability to speak
• drooping of one side of the face
• visual problems, such as loss of vision in one eye, or double vision
• Other symptoms can include dizziness or trouble with balance, confusion, or severe headache

These symptoms usually come on quite suddenly. They can last anywhere from a few minutes to longer. These symptoms are associated with a stroke also. In a TIA, symptoms usually improve in less than 1 hour.

What causes a TIA?

A TIA is caused by a sudden interruption in the blood flow to one part of the brain. As a result, that part of the brain stops to function normally, and one develops problems in the area that it "controls" eg speech, balance, movement, etc. In a TIA, the interruption of blood flow is temporary. When the blood flow is restored, normal brain function is restored also. (In a stroke, the blood flow is interrupted permanently, and function is not restored).

Why are we concerned about TIAs?

A patient who has a TIA has a very high risk of going on to have a full stroke - the risk is thought to be as high as 10% (or 1 in 10) in the 30 days following a TIA. One third of patients who have a TIA will eventually have a stroke. A TIA is considered a "warning sign" that we need to act quickly to do everything possible to reduce the chance of a stroke occurring.

Who is at risk for having a TIA?

Risk factors for developing a TIA include:

• cigarette smoking
• high blood pressure
• diabetes
• high cholesterol
• irregular heart beat (known as "atrial fibrillation")

What should I do if think someone is having a TIA?

This person should be seen by a physician as soon as possible. If the patient is continuing to have any symptoms of a TIA/stroke, call 911 to have ambulance transport to the emergency department.

What will be done in the emergency department?

In the emergency department, the following are usually performed for investigation of a TIA:

• The physician will perform an examination to check heart and brain function, and see if there are any signs of stroke
• Lab tests are often sent to check blood sugar, blood count, and kidney function
• An electrocardiogram, or ECG, checks the heart rhythm
• A CT scan of the head is done in some instances. This is a special kind of computerized x-ray that will detect problems such as bleeding in the brain

What happens if a TIA is diagnosed?

If a TIA is diagnosed, it is imperative to do everything we can to try and prevent progression to a full-blown stroke. This includes:

• Starting blood thinning medication to reduce risk of stroke. Common medications prescribed include Aspirin(ASA), Plavix (Clopidogrel), or Aggrenox (Dipyradimole-ASA)
• Stopping smoking
• Close followup and treatment of any high blood pressure, diabetes, and elevated cholesterol

An ultrasound of the heart (echocardiogram) may be ordered, to look for blood clots in the heart. An ultrasound of the neck arteries (carotid dopplers) may be done, to look for blockages in these arteries. It is essential to have close followup with the family doctor. The patient may be referred to a specialist in St. Thomas or the TIA clinic at London Health Sciences Centre.

All patients are advised to return immediately to the emergency department with a recurrence of symptoms of a TIA.

More information on TIA and Strokes can be found at  Canadian Heart and Stroke Foundation website and  American National Institute of Neurological Disorders and Stroke website on "Brain Basics:Preventing Stroke"