Towards the Design and Development of a Robotic Transcatheter Delivery System for Mitral Valve Implant.

Minimally-invasive surgeries using transcatheter approaches and sophisticated imaging modalities are gaining popularity to treat mitral regurgitation (MR). This paper proposes the next generation of a robotic catheter to deliver an implant onto the mitral valve (MV) through a transseptal approach. The proposed robot has an outer diameter (OD) of 5.7 mm, a rigid distal end length of 20 mm, a prismatic tube that can be advanced by 50-60 mm, and a bending joint that can easily bend 120° to reach the valve opening. The implant can be rotated 75° bidirectionally by the distal torsion joint to orient it with the MV leaflet for precise implantation. The robotic joints are modeled individually, the forward and inverse kinematics are derived, and the robot motion validation is carried out through experimentation. A modified kinematics (MK) model, Prandtl-Ishlinskii (PI) hysteresis model, and hybrid of MK and PI model are used to compensate for the catheter nonlinearities. A preliminary study is conducted to evaluate if force sensing can be used to compensate for the effects of fluid flow. Also, the implantation procedure is demonstrated in a phantom heart.