Effect of preload on left atrial function: evaluated by tissue Doppler and strain imaging

Area of Science:

• Cardiology
• Nephrology
• Medical Imaging

Background:

• Left atrial (LA) function is crucial for cardiovascular health.
• Strain and strain rate (SR) are echocardiographic measures of myocardial deformation.
• Their volume dependency in assessing LA function requires further investigation.

Purpose of the Study:

• To evaluate the preload dependency of LA strain and SR.
• To assess the impact of preload reduction via hemodialysis on LA function parameters.
• To determine the utility of these parameters in end-stage renal disease (ESRD) patients.

Main Methods:

• Transthoracic echocardiography was performed on 41 ESRD patients before and after hemodialysis (HD).
• LA strain, peak tissue velocity, and SR were measured from basal, septal, lateral, inferior, and anterior walls.
• Measurements included systolic and early/late diastolic periods.

Main Results:

• Mean LA strain decreased significantly after HD (23.89% to 21.88%, P=0.019).
• Systolic and early diastolic SR also showed significant changes post-HD (P=0.001 for both).
• Late diastolic LA peak tissue velocity and SR remained unchanged after preload reduction (P=0.436 and P=0.621, respectively).

Conclusions:

• Late diastolic LA tissue velocity and SR are relatively preload-independent.
• These parameters are valuable for assessing LA contractile function, even after acute preload changes.
• This finding supports their use in clinical evaluation of LA function, particularly in conditions with fluid shifts.