title: Effects of the reduction of preload on left and right ventricular myocardial velocities analyzed by Doppler tissue echocardiography in healthy subjects.
abstract: OBJECTIVE
  Previous studies using Doppler Tissue Echocardiography (DTE) have suggested that the early-diastolic myocardial velocity behaves as a relatively load-independent index of left ventricular relaxation in patients with cardiac diseases; it is not ascertained if this holds true also in normal human hearts.
  
  
  RESULTS
  We assessed the influence of a progressive reduction of preload, obtained by Lower Body Negative Pressure (LBNP), on the diastolic and systolic myocardial waves compared to the inflow patterns estimated in left and right ventricles in nine healthy subjects. LBNP caused a significant decrease in end-diastolic volume, stroke volume and systolic arterial pressure, whilst heart rate increased only at maximum preload reduction; meridional end-systolic stress did not change significantly. The early (E') and late (A') myocardial velocities, at mitral and tricuspid annulus, decreased similarly during lower body suction, so that E'/A' ratio did not change. However, due to reduced early (E) but unchanged late (A) diastolic velocities, the E/A ratio of inflow patterns decreased. Systolic (S') myocardial velocities also decreased during LBNP. LBNP induced greater changes of myocardial diastolic and systolic velocities in the right than in the left ventricle.
  
  
  CONCLUSIONS
  In this study, myocardial E', A' and S' velocities, in both the left and the right ventricle, were significantly affected by preload in healthy subjects. Our results support the usefulness of the E'/A' ratio as a relatively load-independent index of diastolic function.
authors.affiliation: Dipartimento di Clinica Medica, Nefrologia e Scienze della Prevenzione, Università degli Studi, Via Gramsci 14, 43100 Parma, Italy. giovanna.pela@unipr.it
authors.forename: Giovanna
authors.initials: G
authors.lastname: Pelà
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Regolisti
authors.forename: Pietro
authors.initials: P
authors.lastname: Coghi
authors.forename: Aderville
authors.initials: A
authors.lastname: Cabassi
authors.forename: Alberico
authors.initials: A
authors.lastname: Basile
authors.forename: Angelo
authors.initials: A
authors.lastname: Cavatorta
authors.forename: Carlo
authors.initials: C
authors.lastname: Manca
authors.forename: Alberico
authors.initials: A
authors.lastname: Borghetti
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D015150:Echocardiography, Doppler; D006339:Heart Rate / Q000502:physiology; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008297:Male; D008943:Mitral Valve / Q000000981:diagnostic imaging / Q000503:physiopathology; D009200:Myocardial Contraction / Q000502:physiology; D009206:Myocardium / Q000737:chemistry* / Q000473:pathology; D012016:Reference Values; D013223:Statistics as Topic; D013318:Stroke Volume / Q000502:physiology; D014261:Tricuspid Valve / Q000000981:diagnostic imaging / Q000503:physiopathology