Orthostatic intolerance

Abstract

Upheavals such as orthostatic intolerance, neurally mediated syncope, postural tachycardia syndrome, migraine headache, mitral valve prolapse, fibromyalgia, chronic fatigue syndrome and irritable bowel syndrome share many manifestations in common, thus, associations among them have been established. This work is a revision of which we could call in general dysautonomia and simultaneously some proposals are postulated. Chronic orthostatic intolerance: sustained drops in systolic (>20 mmHg) or diastolic (>10 mmHg) blood pressure after standing for 3 minutes that are not associated with an increase in pulse rate of at least 30 beats per minute suggest autonomic deficit. The tilt test is a useful tool to study orthostatic intolerance and syncope, which evaluates the response of the autonomic nervous system in a controlled environment. The serotonin could have a very important role at central level as origin of these upheavals, in where it would cause a sympathetic nervous system persistently hyperactive but hyporeactive to stress. The handling of neurocardiogenic syncope has consisted until the moment in palliative treatments. The treatment can be divided in nonpharmacologic and pharmacologic, where the beta-blockers, fludrocortisone and the midodrine have obtained a better control of the disease. Dysautonomia has a great variety of clinical manifestations, which indicate the necessity to establish a clinical classification, that allow us to make study protocols to reach a better understanding of the physiopathology and diagnosis of the disease, and thus to be able to establish more specific therapeutic options for the best control of our patients.