Acute heart failure (AHF) is the leading cause of hospitalization in people over 65, with the group with preserved ejection fraction (HFpEF) being the most closely related to aging. Among its comorbidities, sarcopenia stands out, and its assessment requires measurement of muscle mass. Muscle ultrasound is an accessible and economical alternative, although its prognostic value is still uncertain. The presence of common pathophysiological mechanisms between HF-PEF and sarcopenia leads to the study of biomarkers to improve their characterization.

Multimodal characterization of sarcopenia, integrating muscle mass and strength with skeletal and cardiac muscle biomarkers, will improve prognostic stratification at discharge in elderly patients with HFpEF hospitalized for ACS. We seek to evaluate the prognostic value of muscle mass estimated by ultrasound, in combination with strength measurements and circulating biomarkers related to sarcopenia, as this could improve the prediction of clinical events after hospitalization for AHF in elderly patients with HFpEF. In addition, ultrasound estimation of muscle mass will be analyzed against BIA, the relationship between skeletal and cardiac muscle will be characterized, and the usefulness of the multimodal approach to sarcopenia will be evaluated.

This study is observational, prospective, and single-center. It will include 110 patients hospitalized for AHF aged ≥80 years. Events will be monitored for 6 months after discharge. Variables include clinical data, ultrasound data (lung, VExUS, and muscle mass), congestion markers (BNP, CA125), biomarkers (GDF-15, sST2, BDNF, and myostatin/follistatin), bioimpedance, and dynamometry. Data will be analyzed using regression models and survival analysis to identify prognostic factors.

This study has the potential to improve the clinical management of patients with acute heart failure by providing key information on its interaction with sarcopenia. The results could help identify more effective strategies to reduce rehospitalization and mortality in these patients, improving their prognosis and quality of life.

Inclusion Criteria:

• Patients with HF-pEF (LVEF ≥50%), hospitalized for AHF, with signs of fluid overload and requiring intravenous diuretic treatment. The diagnosis of HF will be made in accordance with ESC-2021 guidelines based on the presence of typical signs and symptoms, elevated natriuretic peptides (BNP >100 pg/mL or NTproBNP >300 pg/mL), and evidence of underlying structural heart disease by transthoracic echocardiography (performed during admission or within a period of 24 months prior to admission).
• Age ≥ 80 years.
• NYHA functional class II-IV.

Exclusion Criteria:

• End-of-life care.
• Inability to comply with study procedures.
• Already included patients on readmission.

Patients over 80 years of age of both sexes hospitalized for AHF in the Internal Medicine or the Geriatrics wards of a tertiary care hospital, with signs of fluid overload and intravenous (IV) diuretic treatment. The clinical diagnosis of HF will be made based on the presence of typical signs and symptoms, evidence of underlying structural heart disease by transthoracic echocardiography, and elevated natriuretic peptides. Only patients with LVEF ≥50% (preserved) will be included.