Mayr, Patrick N.; Wiesner, Gunther; Kretschmer, Angela; Brönner, Johannes; Hoedlmoser, Herbert; Husser, Oliver; Kasel, Albert M.; Lange, Rüdiger; Tassani-Prell, Peter Protection of the anaesthesiologist´s head from radiation during transfemoral transcatheter aortic valve implantation by a lead cap