Transient ischemic attack (TIA) is a temporary disruption of the brain function, because there is momentarily too little blood in a part of the brains. The sudden loss of function, caused by the lack of oxygen, has disappeared completely within twenty-four hours. Transient ischemic attack, as well as cerebral hemorrhage and cerebral infarction, falls under the heading of ‘stroke’.
The cause of a TIA is comparable to that of a cerebral infarction. A TIA is usually caused by blood clots with fatty material and calcium, which are released from the wall of blood vessels (usually the carotid arteries). These clots are carried along with the blood stream and finally get stuck in the small blood vessels of the brains. Thereby closing a blood vessel and the brains have temporary lack of oxygen. Clumps of platelets or blood clots can also cause a TIA. These can be, for example, transported from the heart to the brains.
The risk of a TIA is increased in case of:
The symptoms of a TIA may vary and are dependent on the location in the brains where the lack of oxygen occurs. The best known signs and symptoms are:
- Paralysis in the face, for example a crooked mouth.
- Weakness or numbness at one side of the body.
- Confused talking and thinking.
- Bad vision.
- Sudden severe headache.
- Dizziness and balancing disorders.
A person may not experience all symptoms at the same time. Moreover, the symptoms mentioned above can be an indication of both a cerebral infarction and a TIA. Only with a TIA, these symptoms usually disappear within five to fifteen minutes. This is because the other arteries in the brains rapidly take over the blood supply of the blocked artery.
It is possible that people have a TIA only once, but TIAs are often repeated, sometimes within one day, sometimes months later. Then, the symptoms are often the same as the first TIA. A TIA can be a precursor to a cerebral infarction. The causes of a TIA and a cerebral infarction are the same. Recognizing and treating the causes of a TIA in time can therefore prevent a cerebral infarction.
After referral to a neurologist, he will listen to the patient’s story for diagnosing transient ischemic attack. Probably a CT or MRI scan of the brains is made. Sometimes, little scars (small infarcts) are found, despite the fact that the symptoms after a TIA disappear quickly. It’s also possible to determine the severity of any constriction in the carotid arteries with duplex examination. If the carotid arteries are severely narrowed, an angiography of the head and neck may be needed. On the basis of this internal vascular examination is decided whether vascular surgery to the carotid arteries is required. Finally, the neurologist may perform examination into heart problems and if necessary refer the patient to a cardiologist.
The treatment of a TIA is aimed to prevent a cerebral infarction. For this, the doctor may prescribe medications, such as medicines for hypertension. If the patient suffers from heart rhythm disorders, he or she will get medication to remedy this. In addition, the patient may receive medications to decrease cholesterol levels. The doctor may also prescribe aspirin to prevent the development of blood clots. Aspirin reduces the risk of a cerebral infarction or a new TIA.
Sometimes, the carotid arteries are so severely narrowed that they have to be dilated by surgery. The fatty deposits to the inside of these arteries are removed then.
About thirty percent of people who have had a TIA, will have a cerebral infarction. In half of them, this happens within one year after the TIA. In the long term, the risk of cerebral infarction is lower, but it still remains. The patients also have a substantial risk of other vascular diseases (for example of the heart or in the legs). After having had a TIA, therefore, working on prevention will always be of great importance.
In order to prevent a future cerebral infarction, the patient should change his or her lifestyle by taking the following measures:
- Improve blood pressure and cholesterol.
- In case of diabetes, to (better) monitor the blood sugar.
- Eat healthy. It’s important that a person eats lots of fish, fruits, vegetables, beans, grain and bread.
- Ensure sufficient exercise and relaxation.
- Get and maintain a healthy body weight.
- Quit smoking.