Heart failure (HF) represents a major problem in today's health care landscape and is expected to grow in the next years due to an aging population and improved treatments. In many cases, the evaluation of the volemia status of patients with left ventricular dysfunction is not easy in the outpatient setting, due to limitations of physical examination in stable patients, as well as the tolerance to chronic HF they have. The aim of this study is to determine whether the bioelectrical impedance analysis (BIA) is useful in determining the real clinical stability of chronic HF, its potential implications for clinical management and patient follow-up, as well as for the adjustment of pharmacological treatment. This study is observational, single-center, single-blind and outpatient. It includes patients with a previous diagnosis of HF and left ventricular ejection fraction (LVEF) ≤ 40%, who are stable at the time of inclusion. Follow-up is estimated to be 12 months.

Endpoints:

The primary end-point is to determine the volemia status of the patients and whether there is a correlation between clinical and analytical parameters and those determined with the BIA. It will also be correlated with the clinical questionnaire (ICEBERG). Secondary objectives: to analyze whether the data obtained with BIA correlate with heart failure events such as hospitalization, change in the functional class of patients, worsening renal function, need for changes in medical treatment or implantation of intracardiac devices. In addition, if data allows it, we will evaluate the relationship with quality of life, cardiovascular mortality, changes in biomarkers (NT-ProBNP (N-terminal pro-B-type natriuretic peptide), Troponin I...), and cost-effectiveness.

Design:

This study was design as a single-center observational study in which patients undergoing to a cardiology consultation were selected and underwent bioimpedance measurement as well as a clinical questionnaire. The aim is to obtain data that will help the execution of a larger study about a broadly use of BIA in the management of HF in the future. This study was approved by an institutional review committee and performed under Helsinki Declaration Guidelines. All patients signed the informed consent before entering the study.

The study population is outpatients attended at cardiology consultations of the Hospital Universitario Fundación Jiménez Díaz, with a diagnosis of stable HF (without admission due to decompensation or first episode of HF in the previous year) and with a LVEF ≤ 40% will be included. We estimate that approximately 100 patients can be included in a 3-month inclusion period.

Study procedures: The variables collected are general medical data, analytical data, including the cardiac biomarker NT-proBNP and answers to the ICEBERG questionnaire. BIA is performed when the patient is included in the study.

For follow-up, a review of the clinical history will be carried out in the next months, including a phone contact with the patient if necessary, to obtain information related to mortality or hospital care due to chronic HF.

Inclusion Criteria:

- Outpatients attended at cardiology consultations of the Hospital Universitario Fundación Jiménez Díaz, with a diagnosis of stable HF and with a LVEF ≤ 40%.

Exclusion Criteria:

• admission due to decompensation or first episode of HF in the previous year
• amputated patients
• Chronic treatment with corticosteroids
• Pregnancy and breastfeeding
• Any clinically significant condition detected at the time of screening that in the opinion of the investigators may impair the safe completion of the study or limit the evaluation of the endpoints.
• Patients who are actively participating in clinical trials other than observational trials.

The study population is outpatients attended at cardiology consultations of the Hospital Universitario Fundación Jiménez Díaz, with a diagnosis of stable HF (without admission due to decompensation or first episode of HF in the previous year) and with a LVEF ≤ 40%