title: [Hyperthyroidism and atrioventricular block. Pathogenic hypothesis. Apropos of a case and review of the literature].
abstract: The authors report the case of a 26-year old male patient who had Graves' disease with a first degree atrioventricular block (AVB) and intermittent episodes of a second degree AVB of the Lucciani-Wenckebach type. These disorders of conduction had features characteristic of a nodal block and disappeared after treatment of the hyperthyroidism. The pathogenesis of atrioventricular conduction disorders in hyperthyroidism remains controverted. The authors put forward the following hypothesis: under the influence of thyroid hormones in excessive amounts, the autonomic nervous system would act by reciprocal excitation and exacerbate a patent or latent hypervagotonia which was pre-existent to the hyperthyroidism. This hypothesis needs to be tested by intracardiac electrophysiological studies with atrial stimulation.
mesh_terms: D000328:Adult; D003389:Cranial Nerve Diseases / Q000503:physiopathology; D004562:Electrocardiography; D004594:Electrophysiology; D006327:Heart Block / Q000209:etiology*; D006801:Humans; D006980:Hyperthyroidism / Q000150:complications* / Q000188:drug therapy; D008297:Male; D014630:Vagus Nerve
vernacular_title: Hyperthyroïdie et bloc auriculo-ventriculaire. Hypothèse pathogénique. A propos d'une observation et revue de la littérature.