A transient ischemic attack, or TIA, is often referred to as a “mini-stroke” because the symptoms are similar to an ischemic stroke but they typically last less than an hour. TIAs occur when blood flow to part of the brain is temporarily blocked, usually by a blood clot. This results in a temporary disruption of oxygen to that area of the brain, causing symptoms like weakness, numbness, vision changes, difficulty speaking, or confusion. Understanding which side of the body a TIA is affecting can help determine where the blockage occurred in the brain.
Stroke vs. TIA
The key difference between a stroke and TIA is that with a stroke, the blockage and symptoms persist, while with a TIA the blockage is temporary and symptoms resolve. However, TIAs should never be ignored – they serve as an important warning sign that a major stroke may be imminent if preventative action is not taken.
When the blood supply to the brain is disrupted, symptoms occur on the opposite side of the body from where the blockage is located. This is because the right side of the brain controls movement and sensation in the left side of the body, and vice versa.
TIA Symptoms
Common TIA symptoms include:
- Weakness, numbness, clumsiness on one side of the body
- Vision loss or double vision
- Slurred speech or trouble understanding speech
- Dizziness or loss of balance
- Difficulty swallowing
- Confusion
- Headache
These symptoms come on suddenly and may mimic a stroke. However, unlike a stroke where symptoms persist, TIA symptoms typically resolve within an hour, though sometimes longer.
What Side of the Body Does a TIA Affect?
If symptoms from a TIA occur on the left side of the body, this indicates the blockage is likely in the right side of the brain. Conversely, right-sided symptoms suggest a blockage in the left brain. Some examples:
- Left-sided weakness or numbness = right brain TIA
- Right-sided weakness or numbness = left brain TIA
- Vision loss in left eye = right brain TIA
- Vision loss in right eye = left brain TIA
- Left-sided facial drooping = right brain TIA
- Slurred speech = left brain TIA (in most people, speech control centers are on the left)
In some cases, a TIA may affect both sides of the body if blood flow is disrupted to a part of the brain that controls both sides. Symptoms affecting both sides could include:
- Loss of balance
- Coordination problems
- Confusion
What Causes a TIA?
The most common cause of a TIA is a blood clot that temporarily blocks an artery leading to the brain. This is often due to atherosclerosis, or buildup of fatty deposits in the artery walls. Atrial fibrillation, a heart rhythm disorder, can also cause clot formation. Less common causes include blood disorders, arteritis, and migraines.
Risk Factors
Some risk factors for TIA include:
- Older age
- High blood pressure
- Smoking
- Diabetes
- High cholesterol
- Family history of stroke/TIA
- Carotid artery disease
- Atrial fibrillation
Diagnosing a TIA
Since TIA symptoms resolve quickly, diagnosis may rely heavily on the person’s description of symptoms. However, several tests may be done to confirm TIA and determine the location of the blockage:
- Physical exam – Checking for neurological deficits like weakness/numbness
- Medical history – Looking for risk factors and previous episodes
- Blood tests – Check for blood disorders or cholesterol problems
- Brain imaging – CT or MRI scan to visualize the brain
- Carotid ultrasound – Looks for narrowing in the carotid arteries in the neck
- Heart tests – EKG or echocardiogram to evaluate heart function
TIA Treatment
Treatment focuses on preventing a future stroke, since someone who experiences a TIA is at high risk of stroke in the days to weeks after. Steps include:
- Blood thinners – Antiplatelet drugs or anticoagulants to prevent clot formation
- Surgery – Carotid endarterectomy to remove plaque blockages in neck arteries
- Angioplasty – Inserting a stent to open a clogged artery
- Lifestyle changes – Quitting smoking, losing weight, exercising, eating healthy
- Managing risk factors – Controling blood pressure, cholesterol, diabetes
When symptoms resolve within an hour, monitoring in the hospital is often not needed unless other concerning conditions are present. However, urgent follow up within a few days is important.
Recovering from a TIA
Full recovery is expected with most TIAs since symptoms are temporary. However, some tips for recovery include:
- Get plenty of rest
- Follow doctor’s orders closely
- Take medications as prescribed
- Go to physical therapy if weakness persists
- Lower stress levels
- Ask for support as needed
- Stay hydrated and eat healthy foods
- Follow up promptly with a doctor for any new or worsening symptoms
Risk of Future Stroke
Someone who has a TIA is at increased risk of stroke within the next 2 days to 2 weeks. About 15-20% of people who have a TIA will go on to have an ischemic stroke soon after. Urgent prevention measures are needed to reduce this risk.
Conclusion
Identifying what side of the body is affected by TIA symptoms helps determine which side of the brain is involved. While TIA symptoms resolve, urgent medical care is critical to prevent a future disabling stroke. With proper treatment, most people recover fully after a TIA.