Prosthesis Type for Aortic- and Mitral-Valve Replacement

To the Editor: Goldstone et al. (Nov. 9 issue) 1 highlight the difficult choices that patients face between the greater durability of mechanical heart valves, with concomitant complications of anticoagulation, and the increased structural valve degeneration and need for reoperation that are associated with biologic heart valves. This study further emphasizes, with contemporary data, the need for new biologic heart valves that are resistant to structural valve degeneration, especially in younger patients. Progress over the past 30 years has been disappointing in achieving this goal. We and others have found that immune injury results from xenogeneic antigens that are present in . . .