Mechanical versus Bioprosthetic Aortic Valves in Middle-Aged Patients: Long-Term Outcomes. (11th April 2019) - Kuhn, Elmar W.; Siskos, Dimitrios; Gerfer, Stephen; Eghbalzadeh, Kaveh; Liakopoulos, Oliver J.; Rahmanian, Parwis; Mader, Navid; Wahlers, Thorsten