Load-independent parameters of diastolic and systolic function by speckle tracking and tissue doppler in hemodialysis patients.

Background: Assessment of diastolic function using conventional Doppler techniques is limited by their significant dependence on volume load status. Whether new echocardiographic methods are load-independent in evaluating left ventricular systolic and diastolic function remains controversial.

Objective: The aim of this study was to identify load-independent echocardiographic parameters for systolic and diastolic function in end-stage renal disease (ESRD) patients undergoing hemodialysis (HD) and to evaluate agreement between the new methods.

Methods: We studied 20 clinically stable patients with ESRD on HD for >4 months (mean age 51+/-12 years, 14 men, four with coronary disease). All had a transthoracic echocardiogram immediately before and after HD. Cardiac chamber volumes, left ventricular ejection fraction, and transmitral Doppler flow (E/A ratio) were determined according to American Society of Echocardiography guidelines. Pulsed tissue Doppler imaging (TDI) was used to record septal and lateral mitral annular velocities. Longitudinal systolic (Sm), early diastolic (Em) and late diastolic (Am) myocardial velocities and strain were determined by color TDI and also by speckle tracking imaging (STI), using apical views. The ratio between the rapid filling wave E and mitral early diastolic filling velocity (E/Em) and the Am/Em ratio were calculated, using spectral Doppler, pulsed TDI, color TDI, and STI.

Results: Mean ultrafiltration volume was 2800+/-820 ml (range 1200-4200 ml). Left atrial (LA) and left ventricular (LV) end-diastolic volumes and transmitral pulsed Doppler flow decreased significantly after HD. Early diastolic myocardial velocities also decreased significantly, regardless of the evaluation method. Filling pressure ratios were high and remained unchanged after HD. LV ejection fraction was >44% in all patients and did not change after HD. Systolic myocardial velocities, by any method, and global and longitudinal strain were also similar before and after HD.

Conclusion: Large acute changes in volume load were associated with significant variations in early diastolic myocardial longitudinal velocities, thus demonstrating the dependence of Em on volume load. By contrast, E/Em ratios appeared to be load-independent, as were systolic function parameters. Pulsed TDI, color TDI, and STI yielded similar results for the assessment of diastolic and systolic myocardial parameters.