Goal The E / (Ea×Sa) index is an echocardiographic parameter to determine a patient's left ventricular filling pressure. This study aims to determine the safety and efficacy of the echocardiographic E / (Ea×Sa) index guided diuretic therapy compared to urine output (conventional) guided diuretic treatment.Material and Methods In this cross-sectional study, patients with heart failure with reduced ejection fraction (HFrEF) who were hospitalized due to acute decompensation episode were consecutively allocated in a 1:1 ratio to monitoring arms. The diuretic dose, which provided 20 % reduction in the E / (Ea×Sa) index value compared to initial value, was determined as adequate dose in echocardiography guided monitoring group. The estimated glomerular filtration rate (eGFR), change in weight, NT pro-BNP level and dyspnea assessment on visual analogue scale (VAS) were analyzed at the end of the monitoring.Results Although the similar doses of diuretics were used in both groups, the patients with E / (Ea×Sa) index guided strategy had the substantial lower NT pro-BNP level within 72 hours after diuretic administration (2172 vs.2514 pg / mL, p= 0.036). VAS score on dyspnea assessment was significantly better in the patients with E / (Ea×Sa) index guided strategy (52 vs. 65; p= 0.04). And, in term of body weight loss (4.93 vs.5.21 kg, p=0.87) and e-GFR (54.58±8.6 vs. 52.65±9.1 mL / min / 1.73 m2p=0.74) in both groups are associated with similar outcomes. In both groups, there was no worsening renal function and electrolyte imbalance that required stopping or decreasing loop diuretic dosing.Conclusions The E / (Ea×Sa) index guidance might be a safe strategy for more effective diuretic response that deserves consideration for selected a subgroup of acute decomposed HFrEF patients.