title: A prospective study of systolic ejection murmurs and left ventricular outflow tract in boxers.
abstract: OBJECTIVE
  To investigate the prevalence and progression of murmurs and the development of the left ventricular outflow tract (LVOT) and flow velocities in the great arteries in boxer puppies through adolescence until three years of age.
  
  
  METHODS
  Nineteen boxer puppies with or without a low-intensity murmur, but without evidence of congenital heart disease, were studied prospectively. Examinations were carried out at 7 weeks, 3, 4, 6, 9, 12 and 36 months of age by cardiac auscultation and Doppler echocardiography.
  
  
  RESULTS
  Presence and intensity of heart murmurs varied in the same dog and between dogs, but flow velocities did not change. Estimated effective orifice diameter (EOD) and indexed EOD was significantly narrower than measured subvalvular and valvular diameters.
  
  
  CONCLUSIONS
  The variability in presence and intensity of low-intensity ejection murmurs is high during growth in boxers.
authors.affiliation: Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Höglund
authors.forename: J
authors.initials: J
authors.lastname: Häggström
authors.forename: C
authors.initials: C
authors.lastname: Bussadori
authors.forename: C
authors.initials: C
authors.lastname: Kvart
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity / Q000662:veterinary*; D001947:Breeding; D004283:Dog Diseases / Q000175:diagnosis* / Q000453:epidemiology; D004285:Dogs; D015150:Echocardiography, Doppler / Q000662:veterinary; D005260:Female; D020022:Genetic Predisposition to Disease; D006337:Heart Murmurs / Q000175:diagnosis / Q000453:epidemiology / Q000662:veterinary*; D008297:Male; D015995:Prevalence; D011446:Prospective Studies