The glutaraldehyde-processed porcine aortic heart valve is similar in its microscopic organization to the human aortic valve (1). It is important to understand the detailed histology of this bioprosthetic valve because distinct components of its leaflets are altered selectively when the valve is initially collected from the pig and stabilized with the commercial glutaraldehyde fixation process. Further structural modifications also occur after the commercially processed valve has been inserted into a patient where it undergoes progressive degeneration
