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Carpentier‐Edwards Perimount Valves—Morphological Findings in Surgical Explants

Valvular heart disease is a growing medical problem in the 20th century, with an increasing number of patients undergoing valve repair and replacement surgery.1 Worldwide, more than 55% of implanted prosthetic heart valves (PHV) are mechanical heart valves (MHV) and 45% are bioprosthetic heart valves (BHV).2 BHV more closely resemble native valves in design than do mechanical valves, and are, therefore, better able to mimic normal blood flow patterns through a three-cusp valve.1 BHV may comprise porcine aortic tissue or bovine pericardium. The Carpentier-Edwards Perimount (CEP) bioprosthesis is a second-generation pericardial valve made of bovine (calf) pericardial tissue.1 The tissue is cut from selected regions of bovine pericardium and mounted on a lightweight Elgiloy frame covered with a porous, knitted polytetrafluoroethylene (PTFE) fabric. The sewing ring is made of molded silicone rubber covered with PTFE cloth, which enables the surgeon to sew the valve into place. Few studies have examined the postimplantation morphological changes in a series of explanted CEP. Herein, we describe such changes in 23 CEP valves, explanted at our institution since the start of their use in 1981.