A transient ischemic attack (TIA), sometimes called a mini-stroke, occurs when blood flow to the brain is temporarily disrupted. Many people wonder if having a TIA means they will inevitably have a full-blown stroke. Here we look at the connection between TIAs and stroke, and how to reduce your stroke risk after a TIA.
What is a TIA?
A TIA has similar symptoms to a stroke, but they do not last as long. The key differences between a TIA and stroke are:
- TIA symptoms appear suddenly and last less than 24 hours, often only a few minutes.
- Stroke symptoms persist for longer than 24 hours and can cause permanent damage.
A TIA occurs when a blood clot temporarily blocks blood flow to part of the brain. Once the clot dissolves, blood flow is restored and symptoms go away. With a stroke, the blood flow stays blocked, leading to brain cell death.
Common symptoms
The symptoms of a TIA are the same as a stroke. Common symptoms include:
- Numbness, weakness or paralysis on one side of the body
- Slurred speech
- Vision problems
- Dizziness or loss of balance and coordination
- Sudden severe headache
- Confusion
Any of these symptoms indicate a medical emergency and the need to seek immediate treatment, even if symptoms are mild or improve quickly.
Causes
The underlying cause of TIAs and ischemic strokes is a disruption in blood supply to the brain. This is usually caused by:
- A blood clot (thrombus) blocking a blood vessel – often due to atherosclerosis or blood clotting disorders
- A fatty deposit or plaque rupturing in a blood vessel
- A narrowed or damaged blood vessel
These conditions allow a blood clot to form and temporarily block blood flow. Risk factors such as high blood pressure, smoking, and diabetes increase your chances of developing blood vessel damage and clots.
Connection between TIAs and stroke
Having a TIA signals a high risk of stroke. About 1 in 3 people who have a TIA will go on to have a stroke, with half occurring within 48 hours after the TIA.
After a TIA:
- The risk of stroke is highest in the first few days and weeks
- Over 10% of strokes happen within 3 months
- Over 15% of strokes occur within one year
The symptoms of a TIA indicate there is already underlying blood vessel damage. This damage persists after the TIA and continues to threaten blood flow to the brain. Any further disruption can more easily trigger a stroke.
Reducing stroke risk after a TIA
Swift evaluation and treatment after a TIA can significantly reduce the risk of a subsequent stroke occurring. It’s vital to seek emergency care if you experience any TIA symptoms.
Your doctor will try to determine the cause of your TIA and assess your risk factors. Tests may include:
- Physical and neurological exam
- Blood tests
- CT or MRI scan
- Carotid ultrasound
- Heart tests such as ECG
Treatment after a TIA focuses on preventing further blood clots and avoiding stroke. This may include:
- Blood thinners or antiplatelet medications to prevent clot formation
- Surgery such as carotid endarterectomy for damaged carotid arteries
- Angioplasty or stents to open narrowed arteries
- Managing other health conditions such as high cholesterol, diabetes, and high blood pressure
- Lifestyle changes like quitting smoking and exercising
When treatment starts early, it’s very effective at reducing stroke risk after a TIA. One study found the risk of stroke in the 90 days after a TIA decreased from 10.3% to 2.1% with urgent treatment.
Key points
- A TIA is a temporary disruption in blood flow to the brain which causes stroke-like symptoms.
- About 1 in 3 people who have a TIA end up having a stroke, with over half occurring within 2 days.
- After a TIA, the risk of stroke is highest soon after the event and remains elevated for several years.
- Seeking immediate medical treatment can significantly reduce your risk of stroke following a TIA.
Conclusion
While a TIA is a strong warning sign for stroke, immediate evaluation and treatment can greatly reduce stroke risk. Starting preventive therapies and lifestyle changes after a TIA can help avoid further blockages in blood vessels supplying the brain.
With prompt care, it’s possible to prevent many strokes that may otherwise occur following a TIA. Being aware of TIA symptoms and seeking urgent medical attention can give you the best chance of avoiding a major stroke.