Mini Stroke-Transient ischemic attack

A 60 year-old gentleman was watching TV, when he suddenly developed paralysis on the left side of his body. He and his family were shocked and immediately called the family doctor. But before the doctor could come, he recovered completely spontaneously. The doctor explained to them that this person had suffered from a transient ischemic attack or TIA in short. TIA is also called a mini stroke because it consists of a sudden neurological deficit which improves in less than 24 hours and hence is transient. TIA 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 before menopause, the feminizing hormones protect them from hypertension and other cardiovascular problems. In case of a TIA, blood supply to part of the brain is cut off leading to paralysis of the affected part. The clot may dissolve or dislodge and move off 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 those attributed to a fully fledged stroke. Obesity, deposition of fat in inner walls of blood vessels, increased blood lipid levels, high blood pressure, diabetes; all these conditions predispose one to TIA. Alcohol and tobacco also increase the risk 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. Thus blood supply to the brain is curtailed, leading to neurological deficit in the affected part. At times there may be formation of a clot in the lower limbs due to prolonged recumbence. Part of this clot may detach and reach the brain causing paralysis of the affected part. Cervical spondylosis is yet another cause for transient ischemic attack, because the small osteophytes (new bones formed) occlude vessels supplying blood to the brain.Whatever may be the cause for this mini stroke, it is very frightening for the patient and onlookers alike. But it always improves within 24 hours. Clinical features depend on the part of the brain that is affected, and are very variable. There may be sudden blindness, paralysis of one or more limbs, and loss of sensation, giddiness, and sudden unconsciousness e.t.c. Symptoms are cured completely, once the blood supply to the affected part of the brain is restored. Diagnosis of TIA is made easy by the history of the 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 a repeat episode of TIA. This is possible when risk factors causing TIA are controlled. 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, the patient is left with long-lasting paralysis which may or may not improve. At times, even with improvement, there may be some sequel causing permanent disability. A 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 the 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 in bed for a long time due to sickness or disability should be encouraged to move their legs while on the bed 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 and dipyradimole are used for this purpose. –rachna212002@yahoo.co.uk