Implantation techniques: a primary consideration in valve surgery.

Clean site preparation for a prosthesis is mandatory to avoid tissue interference with the prosthesis. Oversizing of a prosthesis is fraught with peril. In all types of prostheses, orientation has importance. A prosthesis is designed with consideration for axial flow. Tilting the valve in implantation will likely result in a dysfunctional valve. The sewing ring serves not as a gasket but as an additional factor that increases the possibilities of success of a properly implanted valve by taking advantage of its naturally compliant features.