title: The diversity of left ventricular responses to isoproterenol and dibutyryl cyclic AMP infusion in patients with dilated cardiomyopathy.
abstract: Sixteen patients with dilated cardiomyopathy were studied to define the abnormality of the beta-adrenergic pathway non-invasively, using echocardiographic left ventricular responses to isoproterenol (ISP; 0.02 microgram/kg/min) and dibutyryl cyclic AMP (DBcAMP; 0.1 mg/kg/min) infusion. The increase in fractional shortening induced by ISP (delta FS-ISP) was 9 +/- 6% and that by DBcAMP (delta FS-DBcAMP) was 7 +/- 3%. The patients could be divided into three groups according to their left ventricular response to each agent: Group A; normal response to ISP (delta FS-ISP > or = 11%), Group B-1; poor response to ISP but better response to DBcAMP (delta FS-ISP < 11%, delta FS-DBcAMP > or = 7%; damage to beta-receptors), and Group B-2; poor response to ISP and DBcAMP (delta FS-ISP < 11%, delta FS-DBcAMP < 7%; damage including post receptor levels). Seven patients were in Group A, four in Group B-1, and five in Group B-2. DCM patients had a diversity of left ventricular responses to ISP and DBcAMP, according to the site of damage in the beta-adrenergic pathway.
authors.affiliation: Department of Internal Medicine, University of Tsukuba, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Fujieda
authors.forename: K
authors.initials: K
authors.lastname: Iida
authors.forename: S
authors.initials: S
authors.lastname: Kawao
authors.forename: K
authors.initials: K
authors.lastname: Yukisada
authors.forename: I
authors.initials: I
authors.lastname: Yamaguchi
authors.forename: Y
authors.initials: Y
authors.lastname: Sugishita
mesh_terms: D000328:Adult; D000368:Aged; D003994:Bucladesine / Q000494:pharmacology*; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging / Q000401:mortality / Q000503:physiopathology*; D005260:Female; D006352:Heart Ventricles / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D011943:Receptors, Adrenergic, beta / Q000187:drug effects*; D014463:Ultrasonography; D016277:Ventricular Function, Left / Q000187:drug effects*
chemical_list: D011943:Receptors, Adrenergic, beta; D003994:Bucladesine; D007545:Isoproterenol