Background: Left ventricular ejection fraction (LVEF) is calculated from volumetric change without representing true myocardial properties. Strain echocardiography has been used to objectively measure myocardial deformation. Myocardial strain can give accurate information about intrinsic myocardial function, and it can be used to detect early-stage cardiovascular diseases, monitor myocardial changes with specific therapies, differentiate cardiomyopathies, and predict the prognosis of several cardiovascular diseases. Sacubitril/Valsartan has been shown to improve mortality and reduce hospitalizations in patients with heart failure with reduced ejection fraction (HFrEF). The effect of Sacubitril/Valsartan on LV ejection fraction (EF) and torsion dynamics in HFrEF patients have not been previously described. Results: ARNI group of patients showed improvement of symptoms, LVGLS% and diastolic parameters including, E/A, E/e’, TV, untwist onset and rate after 6 months of therapy in comparison to the traditionally treated patients. The improvement continued for 11 months with in additional significant improvement of systolic parameters in the form of LVGLS%, EF%, Twist, Apical and basal rotations, main dependent parameters for improvement of EF% was LVGLS% and Apical rotation. Conclusion: To our knowledge this is the first study to demonstrate that therapy with Sacubitril/Valsartan in HFrEF patients could create a state of gradual and chronic LV deloading which cause relieving of myocardial wall tensions and decreasing the LV end diastolic pressure this state could cause cardiac reverse remodeling and reestablishment of starling forces proprieties of LV myocardium, which lead to increase of LV ejection fraction.