The durability of different anchoring points and anchoring types in the left ventricle in an ex vivo porcine model

OBJECTIVE: Surgical mitral valve repair, including anchoring in different parts of the mitral apparatus, is the standard of care for severe mitral regurgitation. Various percutaneous approaches have been developed and are currently under development, but are struggling with durable results. This study investigates the durability of different anatomic anchoring points and anchoring types in the left ventricle. MATERIAL AND METHODS: Anchoring was tested with PTFE sutures or a 5 mm helix at three locations: the head of the papillary muscle, the lateral wall of the ventricle, and the apex of the ventricle. An accelerated life test was performed with 300 cycles at 3 N for each anchoring. Durability was assessed by measuring compliance (strain in mm until 3 N is reached), migration (change in strain from the first to the last cycle), and the occurrence of dehiscence. RESULTS: The lowest numerical strain/compliance in the first cycle was observed at the head of the papillary muscle anchoring (both surgical and helix). Migration of strain limits over 300 cycles was seen for all locations. The lowest migration was numerically for helix in the papillary muscle. CONCLUSION: PTFE in the head of the papillary muscle is standard practice in mitral valve repair and was used as a reference in the present study. The anchoring that yielded the most similar results was a helix in the papillary muscle, whereas other anchoring points showed greater compliance and/or migration.