Definition and causes of Transient Ischaemic Attack - TIA
En blodåre, der deler
sig. Blodet (pilen)
strømmer frit i begge
En blodprop, der har
revet sig løs et andet
sted, er på vej. Da
karrets diameter er
større end blodprop-
pen, kan blodet sta-
dig strømme til.
af de lille kar, og om-
rådet, der normalt
får blod fra denne åre,
vil nu mangle ilt.
efter et lille stykke tid,
blodet strømmer igen
frit, og symptomerne
på iltmangel forsvind-
Transient ischaemic attack TIA (transient cerebral ischaemia) is a brief temporary (transient) interruption of the oxygen (ischemia) to the brain. Without adequate supply of oxygen to the brain tissue via the blood the brain cells cannot function and a reduction or cessation of blood flow in an area of the brain will therefore give symptoms in the corresponding part of the body. This can include paralysis of an arm or a leg and impairment of vision and speech.
It is important to distinguish between TIA and a stroke (stroke). The symptoms of the two diseases are similar, but TIA symptoms disappear within 24 hours. However, it is impossible to say which one of the diseases we are talking about when the symptoms start, and you should consult a doctor as soon as possible.
TIA is often desribed as mini stroke and can be a harbinger of a stroke, which perhaps can be prevented, and this is another reason to seek medical attention.
TIA is due mostly to a small blood clots from a narrow vein in the neck for example or because of arteriosclerosis affecting the small blood vessels in the brain or from a heart defect such as atrial fibrillation. The clot temporarily blocks the blood flow to an area of the brain. The clot dissolves quickly so blood can flow freely again and the patient's symptoms cease.
Symptoms of TIA (Transient ischaemic attack)
If symptoms persist less than 24 hours the condition will fall under TIA. In by far the most cases the symptoms only last minutes or a few hours. The symptoms arrive suddenly and may be:
Paralysis of an arm, a leg or half the face
Speech impairment, unintelligible speech or problems understanding
Tingling or numbness in parts of the body
Transient blindness of one eye
Balance and coordination problems
Precautions and diagnosis of TIA
As mentioned TIA may be the sign of serious illness and persons experiencing any of the above mentioned symptoms should therefore seek medical attention right away. The doctor will carry out various examinations and studies to form a detailed diagnosis:
A CT scan of the brain (see image of the brain) would rule out the existence of a stroke
An electrocardiogram ECG will show whether atrial fibrillation is the cause of the symptoms
An ultrasound scan of the neck will show whether a narrow neck arterie may have released a small blood clot to the brain.
Treatment and prevention of TIA (Transient ischaemic attack)
Blood thinners (aspirin) is normally given to prevent new clots from occurring. If atrial fibrillation is the reason stronger anti blood coagulation will be prescribed. If arteriosclerosis is the cause then an endarterectomy operation might be performed to remove the affected lining or a small tube can be inserted in the blood vessel to expand it.
As mentioned the underlying cause of TIA is usually arteriosclerosis. This process is accelerated by a number of life style risk factors that can be eliminated. This is done with quitting smoking and regular exercise. It is also important to lose weight, maintain a low alcohol intake and a healthy diet. Elevated cholesterol is an important risk factor, and even if the cholesterol level is not elevated, it can often be beneficial to lower it with diet change and medicine. If there is elevated blood pressure then blood pressure-lowering medication is prescribed.
Complications and outlook of TIA
TIA is a common disease in the elderly, and in most cases the symptoms disappear without causing any harm. However one third of those being affected by TIA will later have a stroke. It is therefore important to have a diagnosis and take the necessary steps to prevent a future stroke.