Venous system in patients with heart failure and lower extremity edema: rationale and design of a clinical trial

There is reason to believe that there are bidirectional relationships between heart failure (HF) and lower extremity chronic venous insufficiency (CVI). In particular, CVI is considered not only a local disease but also a condition with a systemic hemodynamic impact. However, accumulated data on the relationship between HF and venous system appear largely limited and fragmented. The existing literature lacks studies that have comprehensively assessed the venous system in patients with HF and lower extremity edema, and does not provide information on the prognostic value of such an assessment. This prospective cohort clinical study aims to determine possible associations between HF and venous system status, taking into account CVI, analyze the clinical and pathophysiological mechanisms underlying their interaction, and assess the significance of CVI as a potential predictor of HF progression. The study will include hospitalized patients with HF who have had diuretic therapy initiated or intensified in hospital. Upon admission and discharge, an echocardiogram will be performed to assess right heart function, an lower extremity vein ultrasound, and laser Doppler flowmetry, including the orthostatic and Valsalva maneuvers. The severity of congestion will be assessed based on bioelectrical impedance analysis, lung and abdomen ultrasound, including the VExUS protocol. A separate analysis will be conducted for patients with and without CVI. After 6 months, the incidence of death and rehospitalization due to heart failure will be determined via telephone contact.