TNF and hydrops fetalis: Previous studies also showed that pro-inflammatory cytokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β are upregulated in the cardiac tissue and blood in HF patients and/or experimental animals (18), while inhibition of IL-1β, achieved by blocking antibodies, attenuated major cardiovascular events in patients (19), and HF progression in experimental animals (20).