title: A case of hypertrophic obstructive cardiomyopathy associated with autonomic nervous dysfunction.
abstract: Autonomic nervous dysfunction has recently been considered to be an etiological factor in syncope and sudden death in cases of hypertrophic cardiomyopathy. However, the precise mechanism is still unknown. A 73-year-old woman with obstructive hypertrophic cardiomyopathy was hospitalized with complaints of impaired consciousness; faintness 3 to 4 h after meals, lightheadedness while walking, and syncope during and after defecation and micturition. Faintness was induced by alimentary hypoglycemia related to gastrectomy performed 5 years previously. Lightheadedness and syncope were accounted for by autonomic nervous failure combined with an impairment of alpha 1-adrenoceptor in vasoconstriction and the carotid sinus hypersensitivity which accompanied preceding events such as abdominal pain, defecation and micturition, which could enhance the vagally-mediated baroreceptor reflex.
authors.affiliation: Department of Medicine, Wakayama Medical College, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Shimizu
authors.forename: T
authors.initials: T
authors.lastname: Ueyama
authors.forename: O
authors.initials: O
authors.lastname: Mohara
authors.forename: T
authors.initials: T
authors.lastname: Hano
authors.forename: Y
authors.initials: Y
authors.lastname: Ueno
authors.forename: I
authors.initials: I
authors.lastname: Nishio
mesh_terms: D000368:Aged; D001341:Autonomic Nervous System / Q000503:physiopathology*; D002312:Cardiomyopathy, Hypertrophic / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007024:Hypotension, Orthostatic; D013575:Syncope