title: Cardiac findings during uncomplicated acute influenza in ambulatory adults.
abstract: BACKGROUND
  Previous studies have reported abnormal cardiac findings in up to 43% of ambulatory adults with influenza. This study was conducted to determine the frequency, magnitude, and duration of myocardial dysfunction in such persons.
  
  
  METHODS
  We enrolled 30 previously healthy young adults without known cardiovascular disease who presented to the clinic <or=72 h after onset of influenza symptoms and had a positive influenza antigen test. Most patients received antiviral therapy, and all underwent serial electrocardiography and had blood specimens collected on days 1, 4, 11, and 28 after presentation for measurement of total creatine kinase (CK) level, CK isoenzyme MB (CK-MB) level, troponin I level, and selected cytokine levels. Echocardiography was performed on days 4, 11, and 28.
  
  
  RESULTS
  None of the patients had an elevated CK-MB index or troponin I level. Abnormal electrocardiogram findings were noted in 53%, 33%, 27%, and 23% of patients on days 1, 4, 11, and 28, respectively, but none of the findings were considered to be clinically significant. No patient had significant changes in the ejection fraction or abnormal wall motions.
  
  
  CONCLUSIONS
  Most ambulatory young adults with acute influenza have clinically insignificant abnormal electrocardiogram findings early during the illness. These abnormalities resolve promptly and are not associated with changes in cardiac markers or echocardiogram findings.
authors.affiliation: Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, USA.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Ison
authors.forename: Vicky
authors.initials: V
authors.lastname: Campbell
authors.forename: Chris
authors.initials: C
authors.lastname: Rembold
authors.forename: John
authors.initials: J
authors.lastname: Dent
authors.forename: Frederick G
authors.initials: FG
authors.lastname: Hayden
mesh_terms: D000293:Adolescent; D000328:Adult; D015331:Cohort Studies; D004562:Electrocardiography; D006331:Heart Diseases / Q000150:complications / Q000175:diagnosis* / Q000209:etiology*; D006801:Humans; D007251:Influenza, Human / Q000150:complications*; D008297:Male