In this study patients will be observed that receive an On-X AAP implant for the treatment of a diseased, damaged, or malfunctioning native or prosthetic heart valve. The On-X AAP will be implanted at the discretion of the treating physician. Participating physicians will be asked to provide their observations collected during routine care for patients he/she had decided to treat with the On-X AAP. Written informed consent of the patients for the use of their clinical records for study purposes will be obtained before their data will be collected in the PMCF study. In Europe, every patient will be enrolled prospectively prior to the intervention. In the US, patients can be enrolled retrospectively after the intervention or prospectively prior to the intervention. The data from patients who have died following their implant will be recorded in the database without the requirement for written informed consent after IRB approval.~The period of data collection will be approximately 120 + 6 months (depending on the date of the last follow-up visit) from the surgery for each patient.
The ASCEND post-market clinical follow-up study is undertaken to evaluate safety and clinical performance of the On-X Ascending Aortic Prosthesis (AAP) used in surgical aortic valve replacement.