ABSTRACT
The first aortic homograft valves were implanted in subcoronary position by Ross in 19621 and by Barratt-Boyes in 1964.2 The results were good but the lack of availability of these homografts and the appearance of the more easily implanted glutaraldehydepreserved stented porcine valves made many surgeons use these bioprostheses. In the presence of a stent, whatever its geometry may be, a transvalvular gradient is unavoidable, more stress is exercised on the leaflets of the prosthesis and durability is diminished.
