Renal hemosiderosis in patients with prosthetic aortic valves.

DURING recent years, considerable effort has been directed to the development of effective operative methods for the correction of stenotic and regurgitant malformations of the aortic valve. Initially, reconstructive procedures on the valve were performed, but the results of these operations were generally unsatisfactory. Prosthetic valves were then utilized, and the first ones to gain wide acceptance were constructed of flexible Teflon fabric, either as individual leaflets,1 or as tricuspid facsimiles of the normal aortic valve.2 Flexible Teflon prostheses were utilized at the National Heart Institute for aortic valve replacement between 1961 and 1963, and the early and late experiences with these patients have previously been summarized in detail.3 The initial function of the valves was gratifying, but after a number of months the