Background: Acute congestive heart failure (AHF) is a leading cause of hospital admission, with decongestion serving as the cornerstone of its treatment. In the absence of congestion-specific quantitative measures, however, undertreatment often occurs and it is associated with an increased risk of readmission. Lung ultrasonography (LUS) has high accuracy for detecting extravascular lung water. Its use for guiding decongestion in ambulatory patients has shown a reduction in hospital admission and urgent outpatient visits, whereas data are lacking for AHF inpatients. Our aim is to investigate the effect of a LUS-guided decongestive therapy on early clinical outcomes, as compared to physical examination, in hospitalised AHF adults.

Methods: The ICARUS project is a multicentric, multi-blinded, randomised, controlled superiority study, aiming to recruit 222 adult, hospitalised AHF patients with raised values of natriuretic peptide. Participants will be randomised to a decongestive strategy guided by either daily LUS findings (8-point protocol) or daily physical examination. The randomisation will be stratified by study centre and inclusion delay (i.e. within 24 h or more). The primary outcome is the number of days spent alive and out of hospital in a 40-day timeframe from study inclusion (DAOH-40). Secondary outcomes include successful decongestion, length of hospital stay (index hospitalisation), early readmission and mortality, dyspnoea and quality of life (EQ-5D-5L).

Discussion: Incomplete decongestion at discharge is frequent in patients hospitalised for AHF and it is strongly associated with rehospitalisation and mortality. There is a need to clarify the role of LUS as a guide for decongestive therapies. The ICARUS project will provide strong evidence on the usefulness of LUS as a guide for decongestive therapy in hospitalised AHF patients.

Trial registration: The present protocol is registered in ClinicalTrials.gov (NCT06465498, registered 20 June 2024, https://clinicaltrials.gov/study/NCT06465498) and in the Swiss human research platform HumRes of the Federal Office of Public Health (CCER 2024-00268).