Since the first implant in September 1982, the Medtronic Hancock® II has provided more than 20 years of excellent hemodynamic performance and durability. Design improvements over the past generations include: low profile, flexible stent, Supra-X™ supra-annular placement, T6 anti-calcification tissue treatment, modified fixation process, CINCH® advanced implant system and ULTRA™ minimized sewing ring. Valve sizing is a critical consideration in obtaining optimal hemodynamic performance. This is particular true in small aortic roots. A critical issue is the size of the prosthesis in relation to the patient's annulus.

The objective of this clinical study is to evaluate, at six and twelve months, the hemodynamic performance of the HancockÒ Ultra™ bioprosthesis in the aortic position, to analyze the incidence of patient prosthesis mismatch, correlation of gradients, and to ascertain frequency at which a larger valve size is used vs. a patient's debrided annulus diameter.

Inclusion Criteria:

• Patients who require aortic valve replacement with or without coronary artery bypass grafting or surgical treatment of atrial fibrillation or mitral valve repair.
• Patients who are able to provide informed consent.

Exclusion Criteria:

• Concomitant procedures other than coronary artery bypass grafting, surgical treatment of atrial fibrillation or mitral valve repair.
• Patients indicated for receiving a mechanical prosthesis.
• Patients who will have a replacement of existing valve prosthesis.
• Patients refusing or not able to provide informed consent.
• Patients requiring emergency surgery.
• Patients unable to participate in follow-up

The patient population includes all patients who require aortic valve replacement for heart valve disease (acquired or congenital) and who are candidates for a bioprosthetic valve. Patients will be informed about the aspects of this study and will be asked to give their Informed Consent.