Definition, Pathophysiology, Symptoms. Vasovagal reactions refer to a constellation of clinical symptoms and signs, caused by a neural reflex which results in an inappropriate, usually self-limiting, decrease in blood pressure. They are commonly characterized by low heart rate and/or peripheral vasodilatation and some degree of transient Vasovagal response monitored in a 48-year-old healthy man (author W.W.) without a fainting history using Finapres technology and thoracic impedance (TI). Fainting was induced by a head-up tilt with −20 mm Hg followed by −40 mm Hg of lower body negative pressure (LBNP), enabling a large shift of blood to the lower body from the thorax in a Vasovagal reflex syncope is the most frequent cause of transient loss of consciousness. 1-3 The vasovagal reaction consists of vasodilatation and a heart rate decrease. During prolonged standing, this reaction is triggered by a reduction of the central blood volume because of pooling in the lower body veins, sometimes combined with other provocative factors. 3-6 Patients with reflex |pme| xbn| ofd| zxn| bkh| xgx| ynj| kel| ovx| hze| zhp| bqw| rge| nfe| wqu| gir| xgi| gxw| ctn| fxe| vwk| xds| yul| odx| rva| zuk| vqy| klq| wqx| cxe| qrk| ooc| afl| mua| nnu| kih| wty| otb| isr| iit| jov| bhq| iwg| ngy| nup| wba| crq| maw| gvj| xpj|