Heart failure (HF) is a significant cause of death and the leading cause of hospitalization in patients over 65 years of age. Congestion is the main source of symptoms and the leading cause of hospitalization for HF. Furthermore, congestive signs identified in asymptomatic patients are associated with the risk of developing symptomatic HF. The literature supports a multi-modality / integrative evaluation of congestion, combining clinical examination, laboratory results and ultrasound evaluation. The main objective of the CHF-COVReduced study is to identify congestion markers (clinical, biological and ultrasound) quantified during a consultation or day hospitalization for the monitoring of chronic HF with reduced left ventricular ejection fraction that are associated with the risk of all-cause death, hospitalization for acute HF or IV diuretics injection in a day hospital.