A transient ischemic attack (TIA, or mini-stroke) occurs when a part of your brain gets a temporary lack of blood flow. It causes the same symptoms as a stroke, such as weakness or numbness on one side of your body, sudden dimming or loss of vision, difficulty speaking or understanding language, and confusion. Unlike a stroke, however, TIA doesn’t cause permanent brain damage and usually resolves within 24 hours. TIAs are caused by a blockage in a blood vessel that supplies oxygen and nutrients to your brain. This blockage is typically caused by a clot that forms in your blood vessels and then travels to your brain, but it can also be caused by pieces of fatty material or air bubbles.
If you or someone you know has these symptoms, it is a medical emergency and you should call triple zero (000) for help. Time is crucial, and every minute counts. The best way to remember the most common signs of a stroke is FAST: check their face, can they raise both arms? Does their speech sound slurred? Do they have balance problems? And finally, ask them to walk in a straight line – if they can’t do this, it’s probably a stroke.
It’s important to note that while TIAs aren’t a permanent condition, they do increase your risk of having a major stroke in the future. You’re more likely to have a stroke within 90 days of having a TIA, and half of those that follow a TIA happen within two days. Getting immediate medical attention can reduce your risk of having a full-blown stroke, which can cause long-term disability.
The new definition of TIA was changed in 2009 because it was found that up to 50% of TIAs that were classically defined as lasting less than 24 hours actually showed evidence of brain injury on magnetic resonance imaging (MRI) and could have been treated as a minor stroke. It was also realised that relying on CT alone was not the most accurate method for diagnosing TIA/minor stroke, and that functional/behavioral assessments should be used as well.
Symptoms of TIA can be similar to other disorders, so it’s important to see your doctor or nurse as soon as possible. They’ll be able to tell you what the cause is, and refer you for further assessment. In the meantime, you should take aspirin to help prevent a clot from forming.
Other risk factors for TIA include high blood pressure, smoking and taking some types of medication. You’re also more likely to have a TIA if you’ve had a previous stroke or TIA, and if you have an irregular heart rhythm called atrial fibrillation.
You may be offered lifestyle changes and medicine to help prevent a TIA or a stroke happening again in the future. You might also be offered surgery to unblock your carotid arteries, which are the main blood vessels that supply your brain. However, most people who have a TIA don’t need this treatment.
