Post Market ATS 3f® Aortic Bioprosthesis, Model 1000, Size 19mm

Inclusion Criteria: * The patient required isolated aortic valve replacement with or without concomitant procedures such as coronary artery bypass or another valve reconstruction with an ATS 3f® Aortic Bioprosthesis Model 1000 (size 19mm) between the dates of 1-Jan-2009 and 31-Dec-2009. The three remaining heart valves must be of native tissue. * The patient is geographically stable and willing to return to the implant center for any required follow-up visits. * The patient has been adequately informed and consents to his/her participation in the clinical study, and of what will be required of him/her, in order to comply with the protocol. Exclusion Criteria: * The patient is twenty (20) or less than twenty years of age. * The patient is an intravenous drug and/or alcohol abuser. * The patient presented for implant with active endocarditis. * The patient presented for implant with congenital bicuspid aortic anatomy. * The patient had a previously implanted prosthetic valve that was not replaced by the study valve. * The patient required mitral, tricuspid or pulmonic valve replacement.