The following article from The Korean Journal of Thoracic and Cardiovascular Surgery, “Effect of pulsatile versus nonpulsatile blood flow on renal tissue perfusion in extracorporeal circulation [1],” has been retracted by the Journal Editor-in-chief, Chang-Young Lim.This is a duplicate publication of the same research which was published in ASAIO J 2005;51:30–6 as “The effects of pulsatile flow upon renal tissue perfusion during cardiopulmonary bypass: a comparative study of pulsatile and nonpulsatile flow [2].” Authors submitted this article without permission of the Editor of ASAIO J which retains the permission for publishing in another language.It is a requirement of KJTCVS that same research in another language need a permission from previously submitted Journal Editor.