Objective To analyze the change characteristics of left ventricular energy loss（EL）in chronic kidney disease by vector flow mapping（VFM）technique

and to explore the clinical value of EL in quantitative evaluating left ventricular function in patients with chronic kidney disease.MethodsSixty-one patients with chronic kidney disease were selected in this study

including 42 patients with left rentricular ejection fraction（LVEF）≥50%in group A

19 patients with LVEF<50%in group B

38 healthy adults were enrolled as control group.Left ventricle average EL in early filling phase（E-EL-ave）

atrial filling phase（A-EL-ave）

isovolumic contraction period（I-EL-ave）

and ejection phase（Ej-EL-ave）were acquired and calculated by VFM technique

and the differences of above parameters in each group were compared.Receiver operating characteristic curve was drawn to analyze the diagnostic efficacy of different degrees of left ventricular dysfunction.The relationship between EL in each phase and conventional ultrasound parameters were analyzed.ResultsCompared with the control group

EL in all phases of group A were increased

A-EL-ave was increased in group B

and Ej-EL-ave was decreased in group B.The differences were statistically significant（all P<0.05）.Ej-EL-ave showed a biphasic trend in the control group

group A and group B.Ej-EL-ave had good diagnostic efficacy for early left ventricular function impairment and LVEF<50%in patients with chronic kidney disease（area were 0.907

0.861

respectively

both P<0.001）.Ej-EL-ave was positively correlated with LVEF in the patients with chronic kidney disease（r=0.636

P<0.01）.Conclusion The parameter of Ej-EL-ave measured by VFM technique can be used as a potential new indicator to evaluate the efficiency of left ventricular pump function in patients with chronic kidney disease

which has certain clinical value.