A 60-year-old lady was watching T.V. when she suddenly her left side of body became paralysed. The family was shocked and immediately rushed her to the doctor. But within few hours, she recovered spontaneously in the doctor’s clinic, while under surveillance. The doctor explained that she has had suffered from a transient ischemic attack or TIA in short.
TIA (mini stroke) consists of a sudden neurological deficit which improves in less than 24 hours and hence is transient. It can occur in any age but the probability increases with increasing age. Both men and women can be affected. Women are more affected after menopause because after menopause, the feminizing hormones protecting them from hypertension and cardiovascular problems is reduced in the body..
Here, the blood supply to part of brain is cut off due to occlusion of a blood vessel, leading to paralysis of affected part. The occluding clot may dissolve or dislodge or the surrounding blood vessels may reperfuse the affected area of the brain. Due to this, the paralysis recovers spontaneously in less than 24 hours.
Risk factors for developing TIA are the same as for a stroke. Obesity, increased blood lipid levels, high blood pressure, diabetes, alcohol, tobacco, all these are risk factors for TIA. In case of a hyperactive thyroid gland affecting the heart, or irregular beating of the heart due to any cause, a small clot can break from the heart and pass on to the brain via blood stream, occluding a blood vessel. At times there may be clot formation in lower limbs due to prolonged recumbence. Part of this clot may detach and reach the brain causing paralysis of affected part.
Cervical spondylosis can also cause transient ischemic attack, because the small new bones formed occlude vessels supplying blood to the brain.
Whatever may be the cause, a TIA is very frightening for the patient and onlookers alike. But it always improves within 24 hours.
Part paralysed, depends on the part of brain affected. There may be sudden blindness, paralysis of one or more limbs, loss of sensation, giddiness, and sudden unconsciousness e.t.c. Symptoms are reversed completely.
Diagnosis of TIA is made easily by the history of sudden neurological deficit which improves by itself. It is also important to differentiate it from sudden temporary unconsciousness caused due to electrolyte imbalance, low blood glucose levels, infections like cerebral malaria and encephalopathy, e.t.c. conditions. Relevant laboratory tests aid in diagnosing these conditions. C.T. scan helps to confirm diagnosis of TIA.
At this juncture it is important to assess the risk factors and see that the patient tries to prevent repeat episode of TIA. If risk factors persist, an individual may get recurrent attacks of mini stroke and this may progress to developed stroke, which does not settle easily.
If TIA turns into a developed stroke patient is left with long lasting paralysis which may or may not improve. Mostly some sequel may remain causing permanent disability.
Healthy fat free diet, regular physical exercise, mental relaxation, avoidance of smoking and alcohol, good control of hypertension and diabetes are some measures which minimize chances of having a TIA. Those suffering from cervical spondylosis should use a flat bed for sleeping and do regular exercises to prevent exacerbation of spondylosis and development of TIA. Any person who is on bed for long time due to sickness or disability should be encouraged to move their legs on beds so that clot formation is prevented.
After development of a TIA medicines are given to dissolve the clot present in brain and prevent the further formation of clot. Drugs like aspirin, clopidrogel are used for this purpose.
Dr Rachna Pande,
Specialist, internal medicine