Evaluating preload dependence of a novel Doppler application in assessment of left ventricular diastolic function
Kuo-Chun Hung1, Husan-Li Huang, Chi-Ming Chu
1Second Section of Cardiology, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan.
Insights
Tissue Doppler imaging (TDI) is volume-dependent in hemodialysis patients. Diastolic function assessment requires careful timing, even with TDI, due to volume reduction effects.
Area of Science:
- Cardiology
- Nephrology
- Medical Imaging
Background:
- Left ventricular (LV) diastolic dysfunction is common in hemodialysis (HD) patients, contributing to intradialytic hypotension.
- Conventional Doppler is load-dependent; Tissue Doppler imaging (TDI) was proposed as a load-independent method for diastolic function assessment.
Purpose of the Study:
- To evaluate the impact of HD-induced volume reduction on mitral annular velocities.
- To determine if TDI is truly load-independent in HD patients.
Main Methods:
- 128 uremic patients underwent Doppler echocardiography before and after HD.
- Measurements included mitral inflow velocities and mitral annular velocities using TDI.
- LV dimensions, volume, mass, and systolic function were analyzed.
Main Results:
- Hemodialysis significantly decreased LV size, volume, mass, stroke volume, and cardiac output.
- Peak early (E) and late diastolic (A) mitral inflow velocities and E/A ratio decreased post-HD.
- Mitral annular E' velocity and E'/A' ratio also changed significantly post-HD, indicating volume dependency.
Conclusions:
- Tissue Doppler imaging (TDI) remains volume-dependent in hemodialysis patients.
- LV diastolic function assessment in HD patients requires careful consideration of volume status and timing, even with TDI.
Background:
Left ventricular (LV) diastolic dysfunction, commonly found in hemodialysis (HD) patients, is a major cause of intradialytic hypotension. Conventional Doppler interrogation of mitral flow velocities typically is load dependent. Tissue Doppler imaging (TDI) recently was proposed as a new and relatively load-independent approach to assess diastolic function. The aim of this study is to determine whether HD-related volume reduction affects mitral annular velocities in a large number of patients.
Methods:
One hundred twenty-eight uremic patients underwent Doppler echocardiography 1 hour before and after HD. Two-dimensional and M-mode echocardiography were used to analyze LV size, volume, mass, systolic function, and the inferior vena cava. Doppler signals were obtained from the mitral inflow and TDI of the mitral annulus to measure variations in hemodynamics and LV diastolic filling parameters.
Results:
After HD, LV size, volume, mass, stroke volume, and cardiac output were significantly decreased (all P < 0.001). Peak early (E) and late diastolic velocities (A) and E/A ratio decreased significantly after HD (all P < 0.001). Mitral annulus E' velocity and E'/A' ratio also changed significantly (both P < 0.001), whereas A' did not. Consequently, changes in E and A significantly differed with respect to the varying amount of ultrafiltration (both P < 0.05).
Conclusion:
Our larger cohort study shows that the proposed technique of TDI is still volume dependent. Therefore, LV diastolic function in HD patients must be assessed carefully in a timely manner, even when the new Doppler application is used.
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