Effect of preload alterations by hemodialysis on the time interval between the onsets of early diastolic mitral inflow and annular waveforms

BACKGROUND: The T(Ea-E), which is defined as the time interval between the peak of the R-wave and the onset of early diastolic mitral annular waveform (T(Ea)) minus the time interval between the peak of the R-wave and the onset of early diastolic mitral inflow waveform (T(E)), is recently proposed as a useful index of left ventricular (LV) relaxation. The aim of this study is to determine whether the T(Ea-E) is preload-independent. METHODS: Twenty hemodialysis (HD) patients (9 men; age 64 +/- 9 years) underwent echocardiography 1 hour before and 1 hour after HD was studied. RESULTS: After HD, the body weight (P < 0.001), early transmitral filling wave peak velocity (E) (P < 0.001), the ratio of E to late transmitral filling wave peak velocity (P = 0.011), the early diastolic mitral anuular velocity (Ea) (P = 0.002), E/Ea (P = 0.026), and T(Ea-E) (P < 0.001) decreased significantly, and the T(Ea) (P = 0.047) and T(E) (P = 0.005) increased significantly. In addition, T(Ea-E) had a significant negative correlation with Ea either before (r =-0.457, P = 0.043) or after HD (r =-0.637, P = 0.003). CONCLUSIONS: T(Ea-E), as well as Ea, was a preload-dependent relaxation index. The preload dependence of this newer Doppler parameter limited its utility in evaluating LV diastolic function in HD patients.