Remote Dielectric Sensing (ReDS) for a SAFE Discharge in Patients With Acutely Decompensated Heart Failure: The ReDS-SAFE HF Study

Heart failure (HF) is an increasing epidemic and a major public health priority, affecting more than 6 million patients in the United States of America (1). Specially, acutely decompensated HF (ADHF) is the most common cause of hospitalization in adults older than 65 years, and is associated with high rates of morbidity and mortality. Despite advances in pharmacological treatment and early follow-up programs in HF patients, readmission rates remain unacceptably high (2).

Fluid overload is a key feature in the pathophysiology of ADHF and residual congestion at the time of hospital discharge is one of the main contributors into readmission risk (3-5). Typically, fluid overload has been assessed through symptoms and signs, as well as other tools such as chest X-ray, plasma biomarkers, and echocardiography (6). However, these methods are subject to significant inter-observer variability and can be unreliable for various reasons. Furthermore, recent studies have shown that overt signs of clinical congestion correlate poorly with hemodynamic congestion assessed by invasive means. In recent years, invasive hemodynamic measurements to inform medical management of congestion facilitated by implantable pulmonary artery pressure sensors have been shown to reduce HF readmissions (7). Unfortunately, due to its invasive nature as well as reimbursement and insurance coverage issues, its widespread adoption has been limited.

Thus, the use of a non-invasive assessment of volume status to guide HF management and identify a state of "euvolemia" is an attractive tool, particularly during admission and early phase after discharge, which is a vulnerable period for recurrent congestion (8). The Remote dielectric sensing (ReDS) system is a novel electromagnetic energy-based technology that can accurately quantify changes in lung fluid concentration noninvasively (9). Though limited experience from non-randomized studies suggest that ReDS-guided management has the potential to reduce readmissions in ADHF patients recently discharged from the hospital (10, 11), nevertheless data to substantiate the employment of such as strategy is lacking. The study team hypothesizes that a ReDS-guided strategy to measure the percent of lung water volume as a surrogate of congestion during HF hospitalization will help to determine the appropriate timing of discharge and will accordingly be associated with a better short-term prognosis.