Pharmacological treatment of vagal hyperactivity, a rare but potentially fatal cause of sudden cardiac death

Vasovagal reaction, resulting in bradycardia and/or hypotension in response to a number of stimuli, is usually self limitant, but potentially life-threatening exceptions have been described. Pharmacological treatment of proven efficacy is still lacking and the administered compounds are often chosen on the basis of either case reports or outdated small studies with a short-term follow up. In refractory cases, pacemaker implantation may be considered, although no responder patients represent a severe challenge for clinicians. The aim of this review is to examine the state of the art about this controversial issue.