Adult: mitralvalve: evolving technology

Objective:We sought to develop an instrument that would enable the delivery of artificial chordae tendineae (ACT) using optical visualization of the leaflet inside the beating heart. Methods:A delivery instrument was developed together with an ACTanchor system. The instrument incorporates an optically clear silicone grasping surface in which are embedded a camera and LED for direct leaflet visualization during localization, grasping, and chordal delivery. ACTs, comprised of T-shaped anchors and an expanded polytetrafluoroethylene chordae, were fabricated to enable testing in a porcine model. Ex vivo experiments were used to measure the anchor tear-out force from the mitral leaflets. In vivo experiments were performed in which the mitral leaflets were accessed transapically using only optical guidance and ACTs were deployed in the posterior and anterior leaflets (P2 and A2 segments). Results: In 5 porcine ex vivo experiments, the mean force required to tear the anchors from the leaflets was 3.8 1.2 N. In 5 porcine in vivo nonsurvival procedures, 14 ACTs were successfully placed in the leaflets (9 in P2 and 5 in A2). ACT implantation took an average of 3.22 0.83 minutes from entry to exit through the apex. Conclusions: Optical visualization of the mitral leaflet during chordal placement is feasible and provides direct feedback to the operator throughout the deployment sequence. This enables visual confirmation of the targeted leaflet location, distance from the free edge, and successful deployment of the chordal anchor. Further studies are needed to refine and assess the device for clinical use. (J Thorac Cardiovasc Surg 2019;158:1332-40) From the Departments of Cardiovascular Surgery and Cardiology, Boston’s Children’s Hospital, Boston, Mass; and Division of Cardiovascular Surgery, Taipei Veterans General Hospital, Taipei, Taiwan. This work was funded by the National Institutes of Health under grant R01HL124020. Drs Machaidze and Mencattelli contributed equally to these experiments and this report. Received for publication Nov 13, 2018; revisions received Jan 30, 2019; accepted for publication Feb 10, 2019; available ahead of print April 17, 2019. Address for reprints: Pierre E. Dupont, PhD, Boston Children’s Hospital, 330 Longwood Ave, Enders Building 350, Boston, MA 02115 (E-mail: pierre.dupont@ childrens.harvard.edu). 0022-5223/$36.00 Copyright 2019 by The American Association for Thoracic Surgery https://doi.org/10.1016/j.jtcvs.2019.02.120 Scanning take you page to ac informatio 1332 The Journal of Thoracic and Cardiovascular Surgery c November Instrument for artificial chordae implantation provides tip-camera view of leaflet grasping and anchor delivery.