Background: Assessment of mitral annular velocity by Doppler tissue imaging (DTI) and the propagation velocity of early diastolic filling by color M-mode (Vp) have been proposed as preload-independent indices of diastolic function. The aim of study was to compare these parameters with conventional Doppler transmitral and pulmonary vein (PV) flow velocity for the assessment of isolated left ventricular(LV) diastolic dysfunction in patients on periodic hemodialysis (HD).
Materials and Methods: The study group comprised 18 periodic HD patients in sinus rhythm with normal LV systolic function. Echocardiography was performed at 30 minutes prior to and after HD. Early (E) and atrial (A) peak transmitral flow velocities, peak PV systolic (s) and diastolic (d) flow velocities, peak e and a mitral annular velocities in DTI, and V(p) were measured.
Results: In all patients(60% were male; mean age was 55.0 짹12.5 years, mean HD time: 4.8 짹3.8 years, mean ultrafiltration volume(UV): 2501 짹658 ml), the E/A ratio after HD (0.60 짹0.27) was lower (P < 0.05) than before HD (0.85 짹0.30). E decreased (P < 0.05), whereas A did not. PV s/d after HD (2.28 짹1.51) was higher (P < 0.05) than before HD (1.85 짹0.64). Tissue e/a after HD (0.49 짹0.27) was lower (P < 0.05) than before HD (0.62 짹0.25). Tissue e decreased (P < 0.05), whereas a did not. V(p) after HD (34 짹13 cm/s) was lower (P < 0.05) than before HD (45 짹12 cm/s). In subgroup analysis based on UV, the group having small UV(<2500 ml) showed no significant difference in tissue e/a between before HD (0.56 짹0.31) and after HD (0.51 짹0.26).
Conclusions: Echo Doppler parameters using DTI and color M-mode Doppler, proposed as preload-independent indices of diastolic function, exhibits a pattern of preload dependence especially in the group having large UV. It may shed an possibility that these parameters are only preload independent within certain physiologic limits.