A case of dilated cardiomyopathy manifested by exercise-induced left bundle branch block

Jpn Circ J. 1993 Jun;57(6):573-7. doi: 10.1253/jcj.57.573.

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.

Publication types

  • Case Reports

MeSH terms

  • Bundle-Branch Block / diagnosis
  • Bundle-Branch Block / etiology
  • Bundle-Branch Block / physiopathology*
  • Cardiomyopathy, Dilated / diagnosis*
  • Cardiomyopathy, Dilated / physiopathology
  • Electrocardiography
  • Exercise / physiology*
  • Exercise Test / adverse effects
  • Female
  • Humans
  • Middle Aged