Impact of indoxyl sulfate on left atrial strains in patients with maintenance hemodialysis: a three-dimensional speckle tracking study / 中华超声影像学杂志

ABSTRACT

Objective:To investigate the influence of indoxyl sulfate(IS), a typical protein-bound uremic toxin, on left atrial (LA) functional strains using three-dimensional speckle tracking echocardiography (3DSTE).Methods:From May 2019 to January 2020, 128 individuals were consecutively enrolled, including 37 healthy controls and 91 patients, who received maintenance hemodialysis (MHD) in the blood purification center of Zhongshan Hospital affiliated to Fudan University. Conventional echocardiographic parameters and 3DSTE datas of LA were obtained on interdialytic days.LA reservoir, conduit and contraction strains (LASr, LAScd and LASct) were calculated and compared. IS concentration in plasma was assessed by high-performance liquid chromatography tandem mass spectrometry in the MHD cohort.According to the IS concentration, the MHD group was divided into high and low IS (HI and LI) groups. The LA data were also compared between the two groups and linear regression analysis was used to identify independent impact factors of LA strains.Results:Compared to the control group, MHD group had markedly enlarged LA volumes( P<0.05). With regard to the LA phasic strains, both of LASr and LAScd were decreased( P<0.05), while LASct remained unchanged( P>0.05). Compared to the LI group, LASr, LAScd and LASct of the HI group were significantly decreased(all P<0.05). Correlation analysis showed IS concentration correlated well with LASr( rs=-0.674, P<0.001), LAScd( rs=0.454, P<0.001) and LASct( rs=0.376, P<0.001). After adjustment of age, systolic blood pressure, left ventricular mass index(LVMI), and pulmonary systolic pressure, IS concentration remained independently associated with LASr (β=-0.206, 95% CI=-0.353--0.059, P=0.007). Conclusions:In MHD patients, LA is enlarged, and its reservoir function and conduit function are impaired.LA strains derived from 3DSTE are independently related to the IS concentration in plasma, which can be used for the monitoring and evaluation of IS induced cardiac injury.