title: Clinical manifestations of influenza a myocarditis during the influenza epidemic of winter 1998-1999.
abstract: OBJECTIVE
  The clinical features of myocarditis that developed during the influenza epidemic of winter 1998-1999 were investigated to emphasize the need for medical attention to this disease.
  
  
  METHODS
  Nine patients were treated under diagnoses of acute myocarditis during the winter of 1998-1999. Five (two males and three females, mean age 52 +/- 18 years) were examined with myocarditis associated with influenza A. The diagnosis of influenza A myocarditis was based on electrocardiographic and echocardiographic abnormalities, increased creatine kinase levels and at least a four-fold increase in influenza A virus titers using paired sera.
  
  
  RESULTS
  All patients had preceding flu-like symptoms and fever. Cardiac involvement developed between 4 and 7 days after the onset of influenza symptoms. Dyspnea progressively worsened in three patients, one went into shock and one had persistent fever, cough and mild dyspnea without apparent cardiac symptoms. Three patients had ST elevation associated with Q waves and one had complete left bundle branch block. The creatine kinase levels were abnormally increased and global wall motion of the left ventricle on echocardiography was decreased in all patients. Two patients had diagnoses of fulminant myocarditis. One patient died of pneumonia following cerebral infarction, but the left ventricular dysfunction normalized in the remaining four patients.
  
  
  CONCLUSIONS
  Cardiac involvement occurred between 4 and 7 days after the onset of influenza symptoms, and worsening dyspnea was the most common symptom. Electrocardiography, echocardiography and creatine kinase levels should be checked to determine the potential for cardiac involvement when patients present with suspected influenza associated with worsening dyspnea or prolonged weakness. Increasing the awareness of influenza myocarditis may help in the earlier identification and treatment of this disease during influenza epidemics.
authors: First Department of Internal Medicine, Miyazaki Medical College, Kihara 5200, Kiyotake, Miyazaki 889-1692.
authors: H
authors: H
authors: Onitsuka
authors: T
authors: T
authors: Imamura
authors: N
authors: N
authors: Miyamoto
authors: Y
authors: Y
authors: Shibata
authors: T
authors: T
authors: Kashiwagi
authors: T
authors: T
authors: Ayabe
authors: J
authors: J
authors: Kawagoe
authors: J
authors: J
authors: Matsuda
authors: T
authors: T
authors: Ishikawa
authors: T
authors: T
authors: Unoki
authors: M
authors: M
authors: Takenaga
authors: T
authors: T
authors: Fukunaga
authors: S
authors: S
authors: Nakagawa
authors: Y
authors: Y
authors: Koiwaya
authors: T
authors: T
authors: Eto
mesh_terms: D000328:Adult; D000368:Aged; D017548:Echocardiography, Transesophageal; D004562:Electrocardiography; D005260:Female; D006801:Humans; D009980:Influenza A virus; D007251:Influenza, Human / Q000000981:diagnostic imaging / Q000453:epidemiology*; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009205:Myocarditis / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000821:virology*; D012621:Seasons