title: Use of thallium-201 myocardial scintigraphy for the prediction of the response to beta-blocker therapy in patients with dilated cardiomyopathy.
abstract: This study was performed to evaluate whether thallium-201 myocardial scintigraphy (Tl-201) and iodine-123-metaiodobenzylguanidine (MIBG) myocardial scintigraphy could predict the usefulness of beta-blocker therapy in patients with dilated cardiomyopathy (DCM). Tl-201 and MIBG were performed in 47 patients before beta-blocker therapy. Patients were classified into group A, if their cardiac function improved, and group B, whose function remained unchanged. Two types of extent score (ES) by Tl-201 were proposed to quantitate myocardial damage, mean-2SD (ES-2) and mean-3SD (ES-3). The ES difference between ES-2 and ES-3 was calculated, and according to ES and ES difference, DCM cases were classified into 3 groups: mild-defect type (mild-type), moderate-defect type (moderate-type) and severe-defect type (severe-type). The heart-to-mediastinum (H/M) MIBG uptake ratio was evaluated, and the percent washout ratio of myocardial MIBG was obtained from these data. Group A comprised 18 mild-type, 14 moderate-type and 1 severe-type cases, and group B comprised 5 mild-type, 4 moderate-type and 5 severe-type cases. A significant relation was observed between the defect type on Tl-201 and the response to beta-blocker therapy (p=0.0090). Both H/M MIBG uptake ratios and washout ratio were not significantly different in the 2 groups. Tl-201 may be useful for predicting the response to beta-blocker therapy in patients with DCM.
authors.affiliation: The Second Department of Internal Medicine, Ehime University School of Medicine, Japan. yujihara@m.ehime-u.ac.jp
authors.forename: Yuji
authors.initials: Y
authors.lastname: Hara
authors.forename: Mareomi
authors.initials: M
authors.lastname: Hamada
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Ohtsuka
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Ogimoto
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Saeki
authors.forename: Jun
authors.initials: J
authors.lastname: Suzuki
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Matsunaka
authors.forename: Shigeru
authors.initials: S
authors.lastname: Nakata
authors.forename: Yuji
authors.initials: Y
authors.lastname: Shigematsu
mesh_terms: D019797:3-Iodobenzylguanidine; D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D002227:Carbazoles / Q000627:therapeutic use*; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000503:physiopathology; D000077261:Carvedilol; D005260:Female; D005544:Forecasting; D006321:Heart / Q000503:physiopathology; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008790:Metoprolol / Q000627:therapeutic use*; D008875:Middle Aged; D015999:Multivariate Analysis; D011336:Probability; D011412:Propanolamines / Q000627:therapeutic use*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D013794:Thallium Radioisotopes; D016896:Treatment Outcome
chemical_list: D000319:Adrenergic beta-Antagonists; D002227:Carbazoles; D011412:Propanolamines; D019275:Radiopharmaceuticals; D013794:Thallium Radioisotopes; D000077261:Carvedilol; C021148:bevantolol; D019797:3-Iodobenzylguanidine; D008790:Metoprolol