When Do We Need a Permanent Pacemaker in Neuromediated Syncope

Syncope is a very frequent clinical disease [1]. About 30% of the general population undergo one syncopal episode in their lifetime, while at least 3% faint more than once. Moreover, it is the cause of about 3% of visits to hospital emergency rooms. In most cases, the aetiology of syncope is neuromediated. Neuromediated syncope is related to bradycardia and hypotension caused by an abnormal cardiac activation of baroreceptors and of major vessels. Baroreceptor activation produces a vagal overtone and a decrease in sympathetic efferents, thus leading to bradycardia, vasodilation, and hypotension. Though neuromediated syncope does not directly cause death, it is often associated with severe trauma and, when recurrent, significantly impairs the patient’s quality of life [2–4]. In most cases, neuromediated syncope is an isolated event and patients improve after tilt testing and specialist reassurance regarding their condition [1]. However, some patients continue to have frequent fainting fits and suffer severe functional and psychological limitations which significantly undermine their quality of life. Such patients need specific treatment. The treatment of neuromediated syncope involves behavioural measures for all patients, drug therapy for those who are most symptomatic, and pacemaker implantation in very selected cases [1]. Studies on drugs for the treatment of neuromediated syncope have yielded disappointing results [5–11]. In only two brief small-scale investigations [12, 13] did the drug used prove to be more effective than placebo. Thus, drug therapy for neuromediated syncope is still controversial and remains under examination.