Biodegradable annuloplasty ring two years after implantation: first histological demonstration in human mitral...

Although biodegradable annuloplasty rings have been used in clinics for almost a decade for mitral and/or tricuspid annuloplasty, the fate of the ring at the histological level has not been demonstrated in humans to date. The mitral annulus of a 39-year-old patient who underwent heart transplantation almost two years after annuloplasty was subjected to histological evaluation to demonstrate the mitral annular structures and consequences of biodegradable ring annuloplasty. On examination, the ring was shown to have completely degraded, and a fibrous band had formed in the posterior mitral annulus. No signs of residual calcification were observed. Neighboring structures such as circumflex artery and the great cardiac vein were intact. It can be concluded that the biodegradable annuloplasty ring is completely degraded in humans after implantation, leaving a fibrous band behind to support the posterior annulus. The risk of circumflex artery and great cardiac vein injury may not be considerable if the correct implantation technique is used.