Atrioventricular Block in Young Subjects Induced by Vagal Hyperactivity and Interest of Exploring the Autonomic Nervous System: About 4 Cases

Vagal hyperactivity, which corresponds to excessive activity of the parasympathetic system, is a frequent cause of syncope, fainting and dizziness, hence the interest of exploring the autonomic nervous system (ANS) for confirmation.

High-degree atrioventricular (AV) block in patients with a history of syncope usually requires pacemaker implantation, therapeutic strategies should also be considered in young patients especially in the case of non-structural cardiopathy.

We report 4 cases of repeated episodes of syncope in young patients who presented at the emergency with an atrioventricular block (AV-block) of different degrees without any structural cardiopathy. The completion of the etiology findings in these patients came out positive for vagal hypersensitivity after ANS test. The patients were placed on diet and pharmacological therapy with a good clinical outcome without the immediate need for cardiac pacemaker implantation.