Background and Objectives£ºThe time interval between the onset of the mitral inflow and the mitral annulus velocity (TE¡¯-E) has been proposed as a new index for representing the left ventricular (LV) relaxation and this is related to the LV filling pressure. This index has been reported to be a preload independent parameter in an experimental canine model. However, the impact of the preload on this index has not been studied in humans.
Subjects and Methods£ºForty-five patients (29 men, mean age: 51¡¾14 years old) who had end-stage renal disease underwent echocardiography immediately before and after hemodialysis (HD). The two-dimensional and Doppler parameters were measured, including the peak early (E) and late (A) transmitral inflow velocity. The mitral annulus velocity (E¡¯) at the septal, lateral, anterior and inferior corners of the mitral annulus, as accessed by Doppler tissue imaging (DTI), and the flow propagation velocity (Vp), as accessed by color M-mode, were also measured. The time intervals between the peak of the R wave and the onset of the mitral E velocity and also between the peak R wave and the onset of E¡¯ at the four corners of the mitral annulus were measured.
Results£ºThe mean ejection fraction was 62¡¾16%. The average weight reduction by the HD was 2.9¡¾1.1 kg. The dimensions of the LV end-diastole, left atrium and inferior vena cava were significantly reduced. After the HD, the peak E, A and E/A ratio, the average peak E¡¯ and the Vp were significantly decreased. The TE¡¯-E did not change significantly after the HD regardless of the LV systolic function.
Conclusion£ºA new parameter for the diastolic function, i.e., the time interval between the onset of mitral inflow and the mitral annulus velocity, appears to be preload-independent in the patients with a normal or decreased LV systolic function.
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