Following the results of the PARADIGM-HF trial, the European Society of Cardiology (ESC) guidelines recommend sacubitril/valsartan to replace ACE inhibitors in ambulatory patients with heart failure with reduced ejection fraction (HFrEF) who remain symptomatic despite optimal therapy and who fit trial criteria. However, the optimal use of sacubitril/valsartan in clinical practice needs further investigation. We report here the cases of 2 patients with HFrEH successfully treated with sacubitril/valsartan in our daily practice. Both subjects presented multiple comorbidities and received an implantable cardioverter defibrillator in primary prevention. In both patients, therapy with sacubitril/valsartan led to prompt (30 days) amelioration of heart function, with a corresponding decrease in NHYA class and without any relevant safety issue.