[Therapeutic possibilities for the management of vasovagal syncopes].

Since the advent of the tilt test, our understanding of the pathogenesis of vasovagal syncope has progressed greatly. Two mechanisms lead to the sudden fall in blood pressure: on one hand a series of interrelated neuroreflexes, and on the other, neuroendocrine effects. Although our understanding is not complete, new therapeutic measures can be proposed beyond simple empiric prescriptions of vagolytic agents. The efficacy of different treatments is yet to be proven due to the need for long controlled trials with large numbers of subjects. In the early studies versus placebo, no significant evidence of a preventive effect against recurrent malaise could be distinguished from the placebo effect. Complementary investigations such as the tilt test also act as a placebo. While firm recommendations for effective prevention cannot be established until the results of controlled trials are available, it is nevertheless possible to propose a reasonable approach to management.