title: Postexercise syncope: evidence for increased activity of the sympathetic nervous system.
abstract: This report describes an association of postexertional syncope with increased levels of circulating catecholamines. A 36-year-old male who experienced postexercise bradycardia and asystole had higher basal plasma norepinephrine (120 versus 68 +/- 6 pg/ml) and epinephrine (18 versus less than 10 pg/ml) but a similar vagal tone (vagal tone index of 5.44 versus 5.81 +/- 1.00 U) when compared with 6 closely matched subjects who underwent an uneventful stress test.
authors.affiliation: Israel Defence Forces, Medical Corps, Tel Hashomer.
authors.forename: M
authors.initials: M
authors.lastname: Arad
authors.forename: A
authors.initials: A
authors.lastname: Solomon
authors.forename: A
authors.initials: A
authors.lastname: Roth
authors.forename: J
authors.initials: J
authors.lastname: Atsmon
authors.forename: B
authors.initials: B
authors.lastname: Rabinowitz
mesh_terms: D000328:Adult; D001143:Arousal / Q000187:drug effects / Q000502:physiology*; D001262:Atenolol / Q000627:therapeutic use; D001919:Bradycardia / Q000188:drug therapy / Q000503:physiopathology; D004837:Epinephrine / Q000097:blood*; D005080:Exercise Test / Q000187:drug effects; D006323:Heart Arrest / Q000188:drug therapy / Q000503:physiopathology; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000503:physiopathology*; D008297:Male; D009638:Norepinephrine / Q000097:blood*; D011433:Propranolol / Q000627:therapeutic use; D013564:Sympathetic Nervous System / Q000187:drug effects / Q000503:physiopathology*; D013575:Syncope / Q000188:drug therapy / Q000503:physiopathology*; D014630:Vagus Nerve / Q000187:drug effects / Q000503:physiopathology
chemical_list: D001262:Atenolol; D011433:Propranolol; D009638:Norepinephrine; D004837:Epinephrine