Valve repair using biodegradable ring annuloplasty: from bench to long-term clinical results

  Annulus remodeling and stabilization with a ring is a necessary step in mitral and tricuspid valve repair to maintain effective leaflet coaptation and improve long-term results. Although conventional rings meet the basic needs of adults, they do not preserve the changes in shape and size occurring during the cardiac cycle, and do not allow growth of the native annulus in children. The bioring annuloplasty ring was developed to allow for annular stabilization, while remaining biodegradable and allowing for growth. It is a curved "C" segment of poly-1,4-dioxanone polymer located on a non-degradable polyvinyl monofilament suture equipped with a stainless steel needle at each extremity. This ring is inserted subendocardially directly into the mitral or tricuspid annulus, away from blood contact. Animal model experiments have shown that it degrades within 12 months of implantation and is replaced by fibrous tissue, which stabilizes the annulus durably, while allowing for annular growth in children. We review the published data, from bench to bedside, as well as the early, mid and long-term clinical outcomes using the biodegradable ring, which shows that biodegradable rings remodel the annulus, reinforce the repair, restore the function of the atrioventricular valve and maintain the three dimensional dynamic motion and geometry of the mitral and tricuspid valves annulus. Growth potential is preserved in children. The mid- and long-term results showed that degradation of the device occurred without negative observable consequences.