Abstract Introduction Heart failure with reduced ejection fraction (HFrEF) is a major public health concern with substantial morbidity and mortality. Overactivation of the sympathetic nervous system is a key pathophysiological process driving heart failure progression. Baroreceptor activation therapy (BAT) targets this autonomic imbalance and is a promising treatment strategy for patients with HFrEF. Current short-term studies indicate that BAT provides symptomatic relief, improvement in left ventricular function and cardiac biomarkers. However, data regarding the long-term effect of BAT on HFrEF are scarce. Purpose This study aims to assess long-term outcome in HFrEF patients who underwent BAT. Methods Patients with HFrEF who received BAT between 2014-2023 were followed until latest available follow-up. Symptom burden, echocardiography and laboratory testing were assessed before BAT implantation and in subsequent follow ups. Results 23 patients (mean age 66±10 years, 83% men) with HFrEF were included in the study. Etiology of heart failure was ischemic in 70%. The majority of patients (96%) suffered from NYHA III with a mean left ventricular ejection fraction (LVEF) of 23±8% and NTproBNP of 2463±2922pg/ml. Complication occurred in one patient during BAT implantation (4%). Mean follow-up was 3±2 (max. 7.5) years. BAT reduced NYHA classification in 12 patients (52%) after 1 year, of which 1 patient remained in ameliorated NYHA for 7.5 years. Evolution of NYHA functional class over time is shown in Figure 1. Echocardiographic evaluation revealed significant improvement in LVEF of 9±9% after 1 year (p<0.001) and by 11±9% after 2 years (p=0.005). In long-term a trend towards improved LVEF could be observed (Figure 2). In addition, BAT mildly reduced NTproBNP in the first 2 years (after 1 year non-significantly by -396±1006pg/ml and significantly after 2 years by -566±651pg/ml (p=0.039)). Seven patients reaching recommended replacement time underwent device exchange. Four patients deceased during observation time. Conclusion BAT resulted in a substantial reduction in NYHA classification, improvement in LVEF, and a delayed reduction in NTproBNP levels. These findings highlight the long-term efficacy and potential benefits of BAT as a therapeutic intervention for patients with HFrEF.Sankey plot of NYHA class over timeAlteration of LVEF over time