Tissue Doppler Velocity Is Not Totally Preload-Independent: A Study in a Uremic Population after Hemodialysis

Abstract

Objectives: The aim of this study was to investigate the changes of regional tissue Doppler velocity after volume removal following regular hemodialysis (HD) in uremic patients. Is tissue Doppler velocity really preload-independent? Background: Diastolic dysfunction was divided into four stages: normal pattern, abnormal relaxation pattern, pseudonormalization pattern, and restrictive pattern. Pulse wave Doppler and color Doppler echocardiography were important diagnostic tools for these forms of diastolic dysfunction. However, they were preload-dependent and sometimes there was confusion between the normal pattern and the pseudonormalization pattern. Tissue Doppler echocardiography was promising for problems in diastolic dysfunction and appeared to be preload-independent. However, there are still some disputes over this point. Methods: Ninety-three uremic patients receiving regular HD were included in the study. There were 45 males and 48 females aged 59 ± 14 years. The mean volume removed after HD was 2.3 ± 0.9 kg. The mean heart rates before and after HD were 77 ± 11 and 76 ± 12 beats per minute, respectively (p = 0.73). All patients received complete transthoracic echocardiography examinations before and after HD. The studies included cardiac chamber size, left ventricular systolic performance, pulse wave Doppler echocardiographic data of mitral inflow and the right upper pulmonary vein including peak velocity of early diastolic E wave, E wave time velocity integral (TVI-E), peak velocity of late diastolic A wave, A wave TVI, systolic phase of pulmonary vein (S wave TVI), early diastolic phase of pulmonary vein (D wave TVI) and atrial contraction phase of pulmonary vein (Ar wave TVI). Pulsed tissue Doppler echocardiography (TDE) was performed and a 4-mm sample volume was placed at the 6 corners of the mitral annulus including septal, lateral, anterior, inferior, anteroseptal and posterior corners. Five to ten cardiac cycles were recorded and the data were averaged. Measurements performed included peak velocity of systolic phase (Sa), early diastolic phase (Ea), late diastolic phase (Aa), Ea/Aa ratio and time from the beginning of electrocardiogram Q wave to the beginning of Sa (Q-Sa time). The same measurements were repeated after HD. Results: After HD, left atrium diameter and left ventricular internal dimensions at end diastole became smaller. There were significant reductions for mitral peak E wave velocity, TVI-E, peak A wave velocity and E/A ratio. As for the pulmonary vein, systolic phase of pulmonary vein and early diastolic phase of pulmonary vein decreased significantly. Peak Ar wave did not change significantly. For TDE, Sa and Aa did not change but Ea did decrease. Conclusion: After HD, there is a significant reduction of intravascular effective volume. No significant change is found for myocardial peak systolic velocity and peak late diastolic velocity. However, there is a significant reduction of myocardial early diastolic phase peak velocity. This suggests that TDE is not completely preload-indep...

Effect of Food Intake on Commonly Used Pulsed Doppler and Tissue Doppler Measurements

“…Thus the situation after food intake does not correspond from a hemodynamic point of view to other situations where loading conditions have been altered. The impact of changes in loading conditions on pulsed Doppler and tissue Doppler variables has been investigated in several different ways such as after tilt‐test, hemodialysis, active change of posture, nitroglycerine application, leg lifting 31–37 . Our findings that mitral and pulmonary venous flow changed after a meal are in concordance with several previous investigations that have used other methods of changing loading conditions.…”

Reported normal values and weighted means for commonly used echocardiography pulsed Doppler and tissue Doppler measurements

“…Overall, PW over the mitral valve or in the pulmonary vein is more prone to be affected than TDI. The impact of changes in loading conditions on PW and TDI variables has been investigated in several different ways such as after tilt‐test, haemodialysis, active change of posture, nitro‐glycerine application, leg lifting or food intake (Stoddard et al ., ; Downes et al ., ; Voutilainen, ; Møller et al ., ; Barberato et al ., ; Baldi et al ., ; Lee et al ., ; Dencker et al ., ). Most of these changes in loading conditions are irrelevant in clinical practice and to the data in this summary, because you usually know the subjects′ posture or at which elevation they have their legs.…”

“…Weighted mean for reported values from selected studies c 20-29 years 30-39 years 40-49 years 50-59 years 60-69 years 70-79 years 80-89 years e' sept (cm s À1 ) (n = 3035) (Munagala et al, 2003;Park et al, 2007;Daimon et al, 2008;Innelli et al, 2008;Okura et al, 2009;Boyd et al, 2011). been investigated in several different ways such as after tilttest, haemodialysis, active change of posture, nitro-glycerine application, leg lifting or food intake (Stoddard et al, 1989;Downes et al, 1990;Voutilainen, 1994;Møller et al, 1999;Barberato et al, 2004;Baldi et al, 2007;Lee et al, 2007;Dencker et al, 2011). Most of these changes in loading conditions are irrelevant in clinical practice and to the data in this summary, because you usually know the subjects 0 posture or at which elevation they have their legs.…”

Preload dependence of Doppler tissue imaging-derived indices in adolescents

“…Some studies in adults have shown that, in contrast to standard pulsed Doppler indices of left ventricular filling and Color M-mode flow propagation velocity, diastolic velocities of the mitral annulus assessed by DTI are relatively independent of preload [3]. Other studies have revealed contradictory results [4][5][6][7][8][9][10][11].…”