title: Left ventricular mechanics during exercise: a Doppler and tissue Doppler study.
abstract: OBJECTIVE
  To study left ventricular mechanics of exercise with Doppler and tissue Doppler.
  
  
  RESULTS
  Twenty-one males (mean age, 26; height, 184 cm; weight, 84 kg), exercised on a bicycle, with increasing workload, with oxygen uptake, Doppler flow and tissue Doppler recordings during exercise. There was correlation between peak systolic LVOT flow and annulus velocity; R=0.72, (p<0.001) and between peak mitral E flow and annulus E(a) velocity; R=0.68(p<0.001). Finally there was correlation between peak LVOT and mitral flow velocity; R=0.83(p<0.001) and peak systolic and early diastolic annulus velocity R=0.69(p<0.001). All intervals of the heart cycle decreased with RR-interval. There was a linear relation between diastolic filling and RR-interval, while ejection period was less increased with RR-intervals above 600 ms, and thus not a linear relationship. There was no change in E/E(a) ratio during exercise.
  
  
  CONCLUSIONS
  Mechanism for increased filling as well as ejection during exercise seems to be increased contraction and relaxation velocity, with no evidence of Frank-Starling mechanism. Bazett's formula gives a better heart rate correction of LVET at high heart rates than Weissler's.
authors: Department of Circulation and Medical Imaging, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway. a-stoe@online.no
authors: A
authors: A
authors: Stoylen
authors: U
authors: U
authors: Wisløff
authors: S
authors: S
authors: Slørdahl
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity; D015150:Echocardiography, Doppler; D006339:Heart Rate; D006801:Humans; D008297:Male; D008943:Mitral Valve / Q000000981:diagnostic imaging; D009200:Myocardial Contraction; D010101:Oxygen Consumption; D005082:Physical Exertion / Q000502:physiology*; D016277:Ventricular Function, Left