title: Evidence of increased electro-mechanical delay in the left and right ventricle after prolonged exercise.
abstract: We assessed the time delay from the onset of QRS (Q) to peak systolic (S') and diastolic (E') tissue velocities in the left (LV) and right ventricle (RV) before and after prolonged exercise. Nineteen well-trained runners (mean +/- SD age, 41 +/- 9 years) had tissue-Doppler echocardiography performed before and after an 89 km ultra-marathon race. Longitudinal tissue motion was analysed in LV basal and mid-wall segments and RV free wall. Electromechanical coupling was assessed by the delay between Q and S' as well as E' tissue velocities. Average data for all segments were adjusted for the R-R interval. Comparisons were made by paired t-tests. An increase in electro-mechanical delay (EMD) was reported post-exercise in systole (Q-S' LV: 131 +/- 20 vs. 175 +/- 27 ms; RV: 171 +/- 34 vs. 258 +/- 35 ms; P < 0.05) and diastole (Q-E' LV: 486 +/- 51 vs. 647 +/- 44 ms; RV: 500 +/- 80 vs. 690 +/- 75 ms; P < 0.05). Further, post-race peak tissue velocities in basal LV and RV wall segments were reduced (P < 0.05). Recovery from prolonged running was associated with an increased "EMD", and reduced peak tissue velocities, in both ventricles.
authors.affiliation: Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK. F.chan-dewar@2006.ljmu.ac.uk
authors.forename: Fang
authors.initials: F
authors.lastname: Chan-Dewar
authors.forename: David
authors.initials: D
authors.lastname: Oxborough
authors.forename: Rob
authors.initials: R
authors.lastname: Shave
authors.forename: Warren
authors.initials: W
authors.lastname: Gregson
authors.forename: Greg
authors.initials: G
authors.lastname: Whyte
authors.forename: Tim
authors.initials: T
authors.lastname: Noakes
authors.forename: Keith
authors.initials: K
authors.lastname: George
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D015150:Echocardiography, Doppler; D022062:Electrophysiologic Techniques, Cardiac; D055724:Electrophysiological Phenomena / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D005260:Female; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010807:Physical Endurance / Q000502:physiology*; D013997:Time Factors; D016277:Ventricular Function, Left / Q000502:physiology*; D016278:Ventricular Function, Right / Q000502:physiology*