title: Tissue Doppler assessment of ventricular function during cycling in 7- to 12-yr-old boys.
abstract: OBJECTIVE
  Studies utilizing submaximal supine exercise have indicated that tissue Doppler imaging (TDI) may be useful for assessing ventricular systolic and diastolic function during exercise and might offer a means of detecting patients with early myocardial dysfunction. This investigation of 14 healthy boys ages 7-12 yr was designed to assess measures of inotropic and lusitropic function during maximal upright cycle exercise.
  
  
  METHODS
  Color tissue Doppler imaging (S and E' waves, indicative of systolic and diastolic function, respectively), stroke volume, and mitral peak inflow velocity (E wave) were recorded at rest and during a progressive upright cycle test to exhaustion.
  
  
  RESULTS
  Values of TDI-S and TDI-E' were obtained at exhaustive exercise in all but one subject. Mean value of S rose 163% (3.8+/-1.2 to 10.0+/-2.5 cm.s), and average E' increased by 92% (-6.3+/-2.2 to -12.1+/-3.2 cm.s). No significant changes were observed in the ratio of E' to mitral peak flow velocity (E), suggesting that left ventricular end-diastolic pressure remained stable.
  
  
  CONCLUSIONS
  These data indicate that measurement of TDI is feasible during maximal upright exercise, and velocities obtained may provide insights into ventricular systolic and diastolic functional capacity.
authors.affiliation: Department of Pediatrics, Baystate Medical Center, Springfield, MA 01106, and Department of Kinesiology, University of Illinois, Urbana-Champaign, IL, USA. rowland@bhs.org
authors.forename: Thomas
authors.initials: T
authors.lastname: Rowland
authors.forename: Kevin
authors.initials: K
authors.lastname: Heffernan
authors.forename: Sae Young
authors.initials: SY
authors.lastname: Jae
authors.forename: George
authors.initials: G
authors.lastname: Echols
authors.forename: Bo
authors.initials: B
authors.lastname: Fernhall
mesh_terms: D001642:Bicycling; D001795:Blood Pressure Determination; D002302:Cardiac Output; D002648:Child; D003238:Connective Tissue / Q000000981:diagnostic imaging; D018619:Echocardiography, Doppler, Pulsed; D005080:Exercise Test; D006801:Humans; D008297:Male; D010809:Physical Fitness; D013318:Stroke Volume; D016277:Ventricular Function, Left / Q000502:physiology*