Objective:This study aimed to explore the value of speckle tracing imaging (STI) for assessment of left atrial (LA) function in uremic patients. Methods. One hundred uremic patients were divided into four groups according to the New York Heart Association (NYHA) criteria. Thirty healthy participants were enrolled as a control group. LA functional parameters were determined using conventional echocardiography. The strain rate (SR) curve of LA wall was prepared using STI, and SR in different phases of cardiac cycle were obtained. +Results. The LA maximal volume (LAVmax) increased and LA passive ejection fraction (LAPEF) decreased. The LA active ejection fraction (LAAEF) showed an initial increase followed by a decrease (all p<0.05). The SR of LA lateral wall and interatrial septum (IAS) in systole (SRs-LA, SRs-IAS) and early diastole (SRe-LA, SRe-IAS) showed a steady decrease; the SR of LA lateral and IAS in late diastole (SRa-LA, SRa-IAS) showed an initial increase followed by a decrease. Compared with control group, the SRs-LA and SRs-IAS decreased in four groups with uremia (all p<0.05). A positive correlation was observed between LAPEF and the absolute value of mean peak early diastolic SR (|mSRe|) (r=0.862, p<0.05), and between LAAEF and the absolute value of mean peak late diastolic SR (|mSRa|) (r=0.756, p<0.05). LAVmax showed a negative correlation with mean peak systolic SR (mSRs) (r=-0.878, p<0.05). Conclusion. There was a significant correlation between LA function and LA strain rate in uremic patients. STI can allow for an objective and accurate evaluation of LA function in uremic patients.

Objective: To investigate the value of echocardiography in monitoring hemodynamics of postcardiotomy cardiac shock (PCS) patients before, during, and after weaning from extracorporeal membrane oxygenation (ECMO). Methods: Fifty-two patients were divided into a successful weaning group (Group A, n=23) and non-successful group (Group B, n=29). Hemodynamic parameters measured by echocardiography were collected before, during, and after ECMO. The intra-group changes and inter-group differences were analyzed. Results: In group A, the central venous pressure (CVP), proximal right ventricular outflow tract (RVOT), tricuspid annular plane systolic excursion (TAPSE), velocity of tricuspid valve (TVDV), and systolic velocity of tricuspid annulus (s‘TV) during EMCO were significantly lower than before ECMO. After ECMO, left ventricular ejection fraction (LVEF), systolic velocity of mitral annulus (s‘MV), and velocity-time integral of LV outflow tract (LVOT-VTI) were higher than pre-ECMO, and CVP, LVEF, s‘MV, LVOT-VTI, RVOT, TAPSE, TVDV and s‘TV were higher than during ECMO (all p<0.05). In group B, compared to pre-ECMO, subjects exhibited decreased CVP, RVOT, TAPSE, TVDV and s‘TV during ECMO. TAPSE, TVDV, and s‘TV were continuously lower after ECMO, while CVP and RVOT became higher after ECMO (all p<0.05). After ECMO, LVEF, s‘MV, LVOT-VTI, TAPSE, TVDV and s‘TV in group A were higher than those in group B (all p<0.05). Multiple logistic regression analysis showed that LVEF (OR=1.387, 95%CI: 1.072-1.793, p=0.013) and Tei index (OR=-0.005, 95% CI: 0.000-0.939, p=0.047) were independent factors related to the successfulness of ECMO weaning. Conclusions: Quantitative assessment of both LV and RV by echocardiography is important for ECMO weaning.