Changes in left ventricular and atrial mechanics and function after dialysis in patients with end-stage renal disease.

Background: Hemodialysis (HD) can influence end-stage renal disease (ESRD) patients' circulatory system. The present study aimed to evaluate the effect of volume depletion on left ventricular (LV) and left atrial (LA) function and determine the volume-independent parameters before and after HD in patients with ESRD.

Methods: Between January 2018 and January 2019, we recruited long-term HD patients (n=40, 51.0±16.4 years), excluding those with structural cardiac disease. Echocardiographic parameters, including LV and LA volumes, flow Doppler, pulsed tissue Doppler, and speckle tracking echocardiography (STE) before and after HD (within 24 h), were examined, and the values were compared.

Results: Following HD, alteration in LV end-systolic volume was not detected, whereas LV end-diastolic volume (90.18±23.91 vs. 84.21±23.54 mL, P=0.036) and LV ejection fraction (LVEF; 64.63%±6.56% vs. 62.84%±6.56%, P=0.049) decreased. Peak early diastolic trans-mitral flow velocity (E-wave; 82.22±20.13 vs. 72.43±18.32 cm/s, P<0.001), peak early diastolic tissue Doppler velocity (e'; 6.45±1.88 vs. 5.77±1.63 cm/s, P<0.001) at the septal side of the mitral annulus, the ratio of early to late Doppler velocities of diastolic mitral inflow (0.90±0.27 vs. 0.79±0.23, P<0.001), and the average E/e' ratio (12.54±4.08 vs. 11.28±4.52, P=0.049) decreased significantly. No significant difference was found in peak blood flow velocity at the mitral valve during late diastole and e' at the lateral side of the mitral annulus after HD. LA volume index (35.55±12.61 vs. 30.22±9.80 mL/m2 , P<0.001), tricuspid regurgitation velocity (260.11±36.54 vs. 242.37±32.22 cm/s, P=0.002), and pulmonary artery systolic pressure (33.63±11.29 vs. 29.94±7.80 mmHg, P=0.006) significantly decreased. LV global longitudinal systolic strain (GLS) of 4-chamber view (-24.37%±3.02% vs. -23.38%±3.33%, P=0.019), rather than global circumferential systolic strain, exhibited significant change after HD. Significant changes were also found in LV longitudinal early diastolic strain rate (LSRe; 1.17±0.25 vs. 1.05±0.24 s-1 , P<0.001) and early diastolic global radial velocity (Ve; 2.62±0.59 vs. 2.25±0.67 cm/s, P=0.011) after HD, but not in other strain rates and global radial velocity measurements. LA maximal volume (35.55±12.61 vs. 30.22±9.80 mL/m2 , P<0.001), LA total emptying fraction (54.19%±10.39% vs. 49.63%±11.05%, P=0.009), and LA passive emptying fraction (32.23%±12.86% vs. 26.81%±9.28%, P=0.004) decreased significantly after HD, while LA minimal volume, the volume at the onset of atrial systole, and LA active emptying fraction after HD were not significantly different.

Conclusions: Most indices of systolic (LVEF and GLS of 4-chamber view) and early diastolic function (E-wave, e', LSRe, global radial Ve, and LA passive emptying fraction) were preload dependent. Late diastolic indices, including LV late diastolic global longitudinal strain rate, late diastolic global radial velocity, and LA active emptying fraction, did not change with volume depletion.