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 angiotensin receptor neprilysin inhibitor (ARNI) on left ventricular (LV) ejection fraction (EF) and torsion dynamics in HFrEF patients has not been previously described. Methods: The study involved 73 patients with HFrEF, for all patients Full history was taken, full clinical examination was done. Baseline vital signs, ECG, NYHA classification, conventional echocardiography and STE were done at baseline study and after 6 and 11 months. Basal and apical LV short-axis images were acquired for further off-line analysis. Using commercially available two-dimensional strain software, apical, basal rotation, and LV torsion were calculated. Results: ARNI group of patients showed improvement of symptoms, LV global longitudinal strain (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 the best of 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 EF.

Funding Acknowledgements Type of funding sources: None. Background ARNI has been shown to be superior to enalapril in long term reducing the mortality and hospitalization of heart failure (HF). However short-term effect on diastolic function remain unclear. We sought to evaluate 6 months" effects of ARNI on left ventricular (LV) diastolic parameters determined by speckle tracking and tissue Doppler imaging. Objectives This study aims to evaluate the torsional dynamics and 2D speckle tracking in heart failure with reduced ejection fraction on patients taking angiotensin receptor neprilysin inhibitors (ARNI) and non. Methods This study was carried out in Menoufia university hospitals included 60 patients of HFrEF during the period from august 2019 to January 2020. (50%) of patients was treated with traditional treatment of heart failure and the remaining was treated with ARNI. Data were collected including history and clinical examination. ECG and speckle tracking and tissue Doppler imaging was done to evaluate the diastolic function. Results Our results showed no significant difference between the two groups at baseline. There was significant improvement of the LV diastolic function. Untwist time and untwist onset showed the highly significant parameters of improvement. Conclusion This study concluded that ARNI showed short term improvement of diastolic function of the left ventricle that can be detected by STE. Comparison between the studied groups re Echocardiographic diastolic parameters after 6 months ARNI Traditional P-value (Sig.) Count 30 30 Diastolic dysfunction grade Grade 1 9 (30%) 1 (3.3%) 0.008 (S) Grade 2 18 (60%) 22 (73.4%) Grade 3 3 (10%) 7 (23.3%) Other doppler diastolic parameters E/A 0.93 ± 0.30 1.16 ± 0.26 0.002 (S) E/e" 9.1 ± 1.9 10.8 ± 1.6 <0.001 (HS) TR velocity (m/s) 2.6 ± 0.3 2.8 ± 0.3 0.003 (S) Speckle diastolic parameters Untwist rate (°/s) -65.4 ± 5.2 -60.4 ± 4.5 <0.001 (HS) Untwist onset (ms) 96.8 ± 16.2 106.1 ± 15.7 0.028 (S) Shows comparison between ARNI vs Traditionally treated patients and how the parameters of conventional and STE was improved in favor of diastolic parameters. Abstract Figure. Baseline vs 6 months inbetween studied g