title: A case of dilated cardiomyopathy manifested by exercise-induced left bundle branch block.
abstract: We report an extremely rare case of dilated cardiomyopathy manifested by exercise-induced left bundle branch block. A 63-year-old female came to our hospital because supraventricular arrhythmia had been detected at a check-up. A treadmill exercise test induced left bundle branch block. However, chest X-ray and echocardiography revealed no abnormal finding. Two years later, the patient experienced exertional dyspnea. A chest X-ray examination showed cardiomegaly, and echocardiography showed a moderate impairment of left ventricular function with left ventricular dilatation. The diagnosis of dilated cardiomyopathy was made by left ventricular myocardial biopsy. No previous cases have initially shown exercise-induced left bundle branch block which was followed by left ventricular dysfunction due to dilated cardiomyopathy. Careful long-term observation of the clinical course is necessary in patients with exercise-induced left bundle branch block which shows no significant underlying disease.
authors.affiliation: Division of Cardiology, Yamada Red Cross Hospita Mie, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Aoki
authors.forename: M
authors.initials: M
authors.lastname: Motoyasu
authors.forename: Y
authors.initials: Y
authors.lastname: Simizu
authors.forename: N
authors.initials: N
authors.lastname: Ono
authors.forename: M
authors.initials: M
authors.lastname: Unno
authors.forename: H
authors.initials: H
authors.lastname: Nishikawa
authors.forename: Y
authors.initials: Y
authors.lastname: Kakuta
authors.forename: T
authors.initials: T
authors.lastname: Konishi
authors.forename: T
authors.initials: T
authors.lastname: Nakano
mesh_terms: D002037:Bundle-Branch Block / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D002311:Cardiomyopathy, Dilated / Q000175:diagnosis* / Q000503:physiopathology; D004562:Electrocardiography; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test / Q000009:adverse effects; D005260:Female; D006801:Humans; D008875:Middle Aged