IL1B and hydrops fetalis: The objective of the study is to determine the effects of IL-1 blockade with anakinra on peak VO2 (i.e., primary outcome) derived from cardiopulmonary exercise testing (CPX) after 24 weeks of treatment, as well as the effects of anakinra on cardiac biomarkers, echocardiographic data, noninvasive hemodynamic, body composition analysis, quality of life (QoL) questionnaires, perceived functional capacity and physical activity questionnaires, and HF-related clinical outcomes.