title: [First degree atrio-ventricular block in acute thyrotoxicosis].
abstract: Thyrotoxicosis may present with a variety of cardiovascular symptoms. Sinus tachycardia is the most frequently encountered electrocardiographic abnormality and conduction disturbances are extremely uncommon. We present a case of first degree atrio-ventricular block in a patient with newly diagnosed hyperthyroidism and discuss the underlying pathophysiological mechanisms and the clinical implications from the internist's standpoint.
authors.affiliation: Hospital de Clínicas José de San Martín, Facultad de Medicina, Universidad de Buenos Aires. a.vilches@voyager.com.ar
authors.forename: Antonio R
authors.initials: AR
authors.lastname: Vilches
authors.forename: Jorge
authors.initials: J
authors.lastname: Lerman
mesh_terms: D000208:Acute Disease; D000328:Adult; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D013956:Antithyroid Agents / Q000627:therapeutic use; D005260:Female; D006327:Heart Block / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D006980:Hyperthyroidism / Q000150:complications / Q000175:diagnosis; D008713:Methimazole / Q000627:therapeutic use; D011433:Propranolol / Q000627:therapeutic use; D013971:Thyrotoxicosis / Q000175:diagnosis* / Q000188:drug therapy
chemical_list: D000889:Anti-Arrhythmia Agents; D013956:Antithyroid Agents; D008713:Methimazole; D011433:Propranolol