To the best of our knowledge, this is the first study to examine the association between the number of peripheral blood CD34+ stem cells after 5-day bone marrow stimulation with daily subcutaneous injections of G-CSF (5 μg/kg bid), TNF-α and endothelial function, measured as FMD of brachial artery in patients with advanced HF. Here, TNF is linked to hydrops fetalis.