Homograft Aortic Valve Replacement in Aortic Incompetence and Stenosis.

The surgery of aortic incompetence and calcific aortic stenosis has made disappointing progress, chiefly because of the need for partial or total valve replacement in many of these patients and the technical problems inherent in designing an artificial valve. In rheumatic aortic incompetence it is now fairly clear that total replacement of the valve is almost always required (McGoon, Mankin, and Kirklin, 1963), and in calcific aortic stenosis the lesion is by no means always adequately relieved by decalcifying the cusps, so that partial or total valve replacement is necessary in a proportion of these cases also. Dissatisfaction with the available plastic aortic valve prostheses led to a review of the experimental and clinical experience with homograft aortic valves. The experimental evidence (Murray, 1956; Lam, Aram, and Munnell, 1952; Brewin, 1956; Beall, Morris, Cooley, and De Bakey, 1961), while a little conflicting, suggests that with the host valve rendered incompetent a homograft valve will function in the dog. Clinical experience from Toronto (Murray, 1956; Kerwin, Lenkei, and Wilson, 1962), where homograft aortic valves have been inserted in the descending thoracic aorta in patients with severe aortic incompetence, shows that these valves will function normally for up to six years. The evidence seemed sufficient to justify attempts to insert homograft valves in a subcoronary position in anticipation that they would function better and for longer periods than plastic prostheses. The technique used for inserting the valve was based on experience gained in approximately 100 open operations on the aortic valve and was first used in August 1962 before receiving the report of a similar procedure performed by Ross (1962) at about the same time. The technique has proved very satisfactory and the valves have all continued to function well. Indeed the experience presented here, including necropsy examination of two valves three and a half and four and a half months after insertion, is most encouraging and suggests that homograft aortic valves are worthy of serious consideration for aortic valve replacement.