What is a stroke?
A stroke happens when the blood supply to the brain is interrupted. This can happen when a blood vessel in the brain bursts (hemorrhagic stroke), or when there is some type of blockage that cuts off blood supply (ischemic stroke). When brain cells are deprived of oxygen, they die.
What is a transient ischemic attack (TIA)?
A transient ischemic attack (TIA), also sometimes referred to as a “mini-stroke,” starts like a stroke but only lasts from several minutes up to 24 hours. Unlike a stroke, a TIA does not kill the brain cells, so there is no lasting damage to the brain. However, when a TIA begins, there is no way to tell if a person is having a stroke or a TIA.
Approximately 240,000 adults in the United States experiences a TIA each year. At least another 690,000 adults experience an ischemic stroke. Approximately 15 percent of all patients who have experienced a stroke have had a previous TIA. Patients with TIAs are at a particularly increased risk of having a stroke within the following days to weeks. TIAs should be considered warning signs of potential future strokes.
What are the risk factors for a transient ischemic attack (TIA) or stroke?
Some factors cannot be modified (such as age), while others can (smoking). Risks of TIA and stroke include:
- Older age. The risk of stroke doubles with each decade after age 55 in both men and women.
- Family history of stroke
- Male sex. Men have a higher risk of TIA; women have a higher lifetime risk of stroke.
- Race or ethnicity. African Americans and people of Hispanic ethnicity are at higher risk of TIA and stroke than Caucasian (white) people.
- High blood pressure (hypertension)
- Physical inactivity
- Heart disease
- Atrial fibrillation
- Smoking (both tobacco and marijuana)
- High blood cholesterol levels
- Drug abuse
Symptoms and Causes
What are the symptoms of a transient ischemic attack (TIA) or stroke?
The symptoms of a transient ischemic attack (TIA) and a stroke do not differ. Symptoms generally come on suddenly and can include:
- Difficulty seeing from one or both eyes
- Numbness or weakness in the face, arms, or legs, especially on one side
- Severe headache
- Difficulty walking
- Dizziness, loss of coordination and balance
- Difficulty speaking or understanding words
If stroke or TIA symptoms appear, it is very important to go to the ER to get immediate medical help, even if symptoms resolve!
Diagnosis and Tests
How are transient ischemic attacks diagnosed?
Patients who experience a TIA should be seen by medical providers immediately. Evaluation includes examination by a doctor and diagnostic testing. The doctor will do some simple quick checks to test your vision, muscle strength, and ability to think and speak. Diagnostic testing consists of either a computed tomogram (CT) or magnetic resonance imaging (MRI) scan of the brain and carotid arteries to determine the possible cause of the TIA. Other tests include an electrocardiogram (ECG) of the heart, heart rate, body temperature, sleep study (to look for sleep apnea) and blood work (to look for risk factors for stroke – see above -- that can be treated).
Management and Treatment
How are transient ischemic attacks treated?
Because transient ischemic attacks (TIAs) are considered to be “mini strokes,” the general approach to treating and preventing TIAs is the same as that used to treat and prevent strokes.
Drug treatments based on specific medical findings include:
- If your recent stroke or TIA (within 30 days) was caused by severe narrowing of a major artery in the brain, your doctor may recommend you take the aspirin and clopidogrel (Plavix®) for 90 days.
- If you have an irregular heartbeat (atrial fibrillation), your doctor may recommend treatment with an anticoagulant drug such as warfarin (Coumadin®), apixaban (Eliquis®), rivaroxaban, (Xarelto®), or dabigatran (Pradaxa®).
If atherosclerosis (fatty deposits/“plaques”) are found in the carotid arteries -- the artery that supplies blood to the brain, carotid surgery may be recommended. One of two surgical approaches might be recommended:
- Carotid endarterectomy — surgical removal of the plaque within the carotid artery.
- Carotid angioplasty and stenting procedure —a less invasive alternative treatment appropriate for some patients who have a carotid artery blockage. The procedure involves flattening the build up of fatty plaque or blockage against the walls of the artery, which then allows increased blood flow. The stent (a small, metal mesh tube) remains in place as a permanent scaffold to keep the artery open.
How can the risk of future transient ischemic attacks (TIAs) or stroke be decreased?
To reduce the risk of a future TIAs or strokes, follow these tips:
- If you smoke, stop.
- Monitor your blood pressure and follow your doctor’s treatment plan if your blood pressure is high. The target blood pressure is less than 140/90 mm Hg for all adults who have a history of TIA or stroke. Choice of drug therapy depends on many patient specific considerations.
- Monitor your cholesterol and follow your doctor’s treatment plan if your cholesterol level is high. The target low density liproprotein (LDL) level is less than 100 mg/dl in patients with atherosclerotic stroke or TIA and lower than 70 mg/dl in patients who also have diabetes. Statin drugs are the drugs of choice if drug therapy is recommended.
- Eat a Mediterranean-style diet (a diet high in vegetables, fruits, whole grains, fish, legumes, poultry, olive oil, nuts, and low-fat dairy products). Limit your intake of red meat and sweets. Reduce your salt (sodium) intake to less than 2.4 g/day.
- Maintain a healthy weight.
- Stop drinking alcohol, except in moderation (up to two drinks per day for men and up to 1 drink per day for nonpregnant women).
- Exercise. Engage in three to four, 40-minute sessions of moderate to intense aerobic exercise per week. Moderate to intense exercise means the activity causes you to break a sweat or noticeably raise your heart rate. Examples include a brisk walk or using an exercise bike.
- Wear your CPAP (Continuous Positive Airway Pressure) device if you have been diagnosed with sleep apnea and your doctor recommended use of this device.