Introduction: According to the new European Society of Cardiology Guidelines for Heart Failure may be acute or chronic. According to the left ventricular ejection fraction (LVEF) heart failure (HF) is divided into the preserved (HFpEF, LVEF >50%), mid-range (HFmrEF, LVEF 40-49%) and reduced ejection fraction (HFrEF, LVEF <40%). Sacubitril/valsartan is used in the treatment of HFrEF in patients who, despite of the optimal medical therapy with ACE inhibitors, beta blockers and mineralocorticoid receptor antagonist, have no symptom improvement. In the PARADIGM-HF study, its superiority was demonstrated in relation to enalapril. (1, 2)

Case report: We present a patient with history of rheumatoid fever, mitral valvuloplasty, implanted heart electrostimulator, and multiple (20 times) hospitalizations due to acutization of chronic, dominant right-sided HF. In May 2018 he was hospitalized again at our Clinic because of acutization of dominantly right-sided HF. There was no sign of pulmonary congestion, but with elevated liver transaminases, ultrasound findings of enlarged liver and distended hepatic veins, ascites and peripheral edema. The left ventricle was borderline size, slightly reduced systolic function (LVEF 43%). The right ventricle was dilated with severe tricuspid insufficiency as a result of anulus dilatation and decreased systolic function (VCI 25 mm, TAPSE 14 mm). Value of NT-proBNP 4356 pg/ml. He was treated according to the recommendations for acute HF and after stabilization of the condition for the first time with sacubitril/valsartan. Control echocardiographic finding showed a lower volume of the right ventricle (VCI 19 mm, TAPSE 15 mm). At regular ambulatory control there was clinical improvement, the value of NT-proBNP 873 pg/ml.

Conclusion: Although it has been shown that sacubitril/valsartan in treatment of HFrEF reduces overall mortality and number of hospitalization and improve quality of life, its role in HFpEF and HFmrEF has not been investigated. The PARAGON-HF study is underway to investigate its role in comparison to valsartan in HFpEF. Our patient has fewer clinical symptoms and lowered the level of NTproBNP.