Patients with HF are predisposed to infection-related hospitalizations and short-term mortality when compared with patients without HF.118, 119, 120 Notably, patients with chronic HF have elevated levels of proinflammatory cytokines, including TNFα, IL-1, and IL-6.121, 122, 123 However, the etiology of this systemic immune activation remains unclear. Here, TNF is linked to hydrops fetalis.