Heart valve replacement by porcine aortic valve (Hancock prosthesis).

Glutaraldehyde preservation of heterograft valves has increased their durability. Sixty-nine Hancock prostheses have been implanted, 30 in the mitral position and 39 in the aortic position. Anticoagulants have not been administered. There has been one important thromboembolic complication and periprosthetic mitral incompetence has occurred in three instances, but prosthetic incompetence has not developed. Two asymptomatic aortic diastolic murmurs have been noted. After a follow-up ranging between two and 19 months, it appears that the Hancock prosthesis offers a valuable alternative to mechanical valve replacement and anticoagulants are not required as a routine.