Estimated left ventricular pressure-myocardial strain loop as an index of cardiac work predicts all-cause mortality in patients receiving regular hemodialysis

Background: A non-invasive method for left ventricular pressure-strain analysis has recently been introduced to provide information on cardiac work and detect subtler changes in cardiac function. This study aims to verify and construct a novel index that could accurately and independently predict the prognosis of patients with end-stage kidney disease (ESRD) receiving regular hemodialysis. Methods: Patients with end-stage kidney disease (ESRD) receiving maintenance hemodialysis (4-h sessions, 3 times weekly for 3 months or more) and who underwent echocardiography between 2009 and 2014 in China Medical University Hospital, Taichung, Taiwan, were enrolled. Conventional (left ventricular ejection fraction, LVEF) and strain echocardiography parameters (global longitudinal strain, GLS; cardiac work index, CWI) in 102 eligible patients were analyzed and compared. CWI was calculated from estimated LV pressure-myocardial strain loop area. Results: Results show that, while no significant differences were found between LVEF (0.57 +/- 0.12 vs. 0.59 +/- 0.09, P = 0.27) and GLS (-16.12 +/- 6.57% vs.-18.44 +/- 5.54%, P = 0.07), deceased patients had significantly lower CWI (1339 +/- 683.05 mmHg% vs. 1883.38 +/- 640.99 mmHg%, P = 0.0002) than surviving patients. The predictive values defined by area under the curve (AUC) of LVEF, GLS and CWI were 0.499, 0.619 and 0.724, respectively. Conclusion: In conclusion, CWI is an accurately independent predictor of all-cause mortality in ESRD patients receiving regular hemodialysis and may superior to the current predictors such as LVEF and GLS. (c) 2021 The Authors. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).

Automated summary

The non-invasive method of left ventricular pressure-strain analysis can provide valuable information on cardiac function. Among end-stage kidney disease patients receiving regular hemodialysis, a novel index called CWI has been shown to be an accurate and independent predictor of all-cause mortality, outperforming traditional predictors like LVEF and GLS.