Transient Ischemic Attacks (TIA)

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[edit] Transient ischemic attacks(TIA)

A neurological deficit similar to a mini stroke, but very fleeting in nature and completely reversible within a 1 or 2 hour period, is called a transient ischemic attack. Depending on he underlying pathology this might be harmless or it might be the first sign of an impending disaster. It warrants a careful work-up by a neurologist.

Symptoms:

There is a sudden presentation a focal neurological symptom such as loss of speech, numbness and lack of power in one extremity or visual problems. However, the symptoms only last a few minutes up to at the most 1 or 2 hours. There is usually no loss of consciousness, but there could be a very brief moment of passing out (called "syncope"). These attacks could happen as isolated events, but often happen intermittently 2 or 3 times in a year. If there are frequent TIA's, the patient is at a significantly higher risk of developing a full stroke.

Diagnosis:

Because of the possibility of an impending stroke the presence of an ischemic attack should be considered like a possible first warning of an impending stroke.

In other words, nature gave us a grace period to sort out what is going on. Tests should include a CT scan of the brain and possibly angiogram of the blood vessels to the brain, particularly images of the carotid and vertebral arteries. Ultrasound Doppler studies would also be useful to examine the bifurcation of the carotid arteries and the blood flow through the major neck vessels. An echocardiogram to look for abnormalities of the heart valves would be another useful test. The rationale of all these tests is that the physician is looking for causes for shedding of emboli such as from ragged heart valves or arteriosclerotic plaques in the carotid arteries or the vertebral arteries. The CT scan of the brain rules out an existing stroke, scarring from a previous stroke, a brain tumor and an aneurysm. Some blood tests are also done to rule out diabetes mellitus and autoimmune diseases such as lupus erythematosus.

Treatment:

Sometimes, if the physician finds a marked arteriosclerotic change in the carotid artery with a narrowing of the lumen of 70% or more, a cardiovascular procedure called endarterectomy has proven to be very valuable, as it will not only stop the TIA , but also prevent a stroke.

However, not all findings are as clear as that and the recommendation by the physician will depend on the findings of these and other tests. In the case of a minimal narrowing or the vertebral arteries or carotid arteries, the doctor may prescribe ASA or ticlopidine (brand name: Ticlid, Apo-Ticlopidine or Nu-Ticlopidine) as antiplatelet drugs. With atrial fibrillation as a heart rhythm and blood clots that are shed from the heart chambers, anticoagulant therapy with heparin initially, then a switch-over to Coumadin would be the therapy of choice. In the case of a singular metastasis in the brain from a previously treated melanoma, for instance, life can often be prolonged by an excision of the brain metastasis by a neurosurgeon. This may or may not be followed by radiation therapy.

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