title: Clinical significance of abnormal relaxation pattern of the transmitral flow velocity waveform in older patients with preserved left ventricular ejection fraction.
abstract: BACKGROUND
  The pathophysiology of abnormal relaxation pattern in the transmitral flow (TMF) velocity waveform has not been fully elucidated.
  
  
  RESULTS
  A total of 173 patients who underwent comprehensive Doppler echocardiography and diagnostic cardiac catheterization for coronary artery disease were enrolled in the study. Peak early and late diastolic TMF velocities (E and A, respectively) were measured. Minimum left ventricular (LV) pressure; LV pre-A wave pressure (surrogate of mean left atrial [LA] pressure); time constant (τ) of LV pressure decay; and LV ejection fraction (LVEF) were calculated. Patients with E/A ratio <1.0 and LVEF ≥ 50% were enrolled. Patients with τ ≥ 48 ms and those with τ <48 ms were compared. The 2 groups had no significant differences in E or E/A. Minimum LV pressure (6.9 ± 2.2 mmHg vs. 3.6 ± 2.9 mmHg, P<0.0001) and LV pre-A wave pressure (9.5 ± 2.4 mmHg vs. 6.1 ± 3.0 mmHg, P<0.0001) were significantly higher in patients with τ ≥ 48 ms compared to those with τ <48 ms, but the difference between the LV pre-A and minimum LV pressures was similar between the groups (2.6 ± 1.4 mmHg vs. 2.5 ± 1.5 mmHg, P=0.89).
  
  
  CONCLUSIONS
  Proportional elevations in minimum LV and pre-A pressures, due to deteriorated LV relaxation, resulted in no changes in the pressure gradient between the LA and LV in early diastole, E, or E/A.
authors.affiliation: Department of Cardio-Renal Medicine and Hypertension, Nagoya City University Graduate School of Medical Sciences.
authors.forename: Shohei
authors.initials: S
authors.lastname: Kikuchi
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Wakami
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Goto
authors.forename: Hidekatsu
authors.initials: H
authors.lastname: Fukuta
authors.forename: Hiroo
authors.initials: H
authors.lastname: Sonoda
authors.forename: Tomomitsu
authors.initials: T
authors.lastname: Tani
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Ohte
mesh_terms: D000368:Aged; D000787:Angina Pectoris / Q000000981:diagnostic imaging / Q000503:physiopathology; D001794:Blood Pressure; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000503:physiopathology*; D003971:Diastole; D015150:Echocardiography, Doppler; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013318:Stroke Volume