1. From the Department of Cardiology, Advanced Heart Failure and Transplantation Center (G.P., G.Z., B.V.), Department of Hematology (M.S., P.C.), and Department of Cardiovascular Surgery (I.K.), University Medical Center Ljubljana, Ljubljana, Slovenia; National Blood Transfusion Institute, Ljubljana, Slovenia (M.C.); and Stanford Cardiovascular Institute, Stanford University School of Medicine, Palo Alto, CA (F.H., J.C.W., B.V.).