Observational study on ADHF patients at one site in Israel. After signing informed consent and undergoing screening assessments, eligible patients will record sentences into a smartphone. The app will upload the vocal data to the sponsor's servers for analysis. The patient will record at hospital: admittion, release. Before hospital release, if applicable and upon patient agrreement, an app will be installed in a smartphone in order to continue the recording at home.

Inclusion Criteria:

• Diagnosis of ADHF (pulmonary congestion)
• Known diagnosis of HF, with either preserved or reduced LVEF.
• 18+ years old.
• Able to understand and provide written informed consent.

Exclusion Criteria:

• Subjects unable to comply with the daily use of the application due to mental disorders.
• GFR <25 ml/min who are non-responsive to diuretic therapy or who are on chronic renal dialysis.
• Subjects with congenital heart disease or mechanical right heart valve(s).
• Airway and lung infection and Sepsis
• Patients with severe alcohol or drug use.
• Women who are pregnant or lactating.

Hospitals/ CHF clinics