title: Reply to Yang.
authors.affiliation: Department of Intensive Care Medicine, Imland Klinik Rendsburg, Rendsburg, Germany kevin.pilarczyk@imland.de.
authors.forename: Kevin
authors.initials: K
authors.lastname: Pilarczyk
authors.affiliation: Department of Cardiovascular Surgery, Bundeswehr Central Hospital, Koblenz, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Markewitz
authors.affiliation: Department of Intensive Care Medicine, Imland Klinik Rendsburg, Rendsburg, Germany.
authors.forename: Nils
authors.initials: N
authors.lastname: Haake
authors.affiliation: Department of Anesthesiology, University of Lübeck, Lübeck, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Heringlake
keywords: Aortic counterpulsation; Cardiac surgery; Intraaortic ballon pump