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

Materials Advances in Devices for Heart Disease Interventions

Heart disease encompasses a range of conditions that affect the heart, including coronary artery disease, arrhythmias, congenital heart defects, heart valve disease, and conditions that affect the heart muscle. Intervention strategies can be categorized according to when they are administered and include: 1) Monitoring cardiac function using sensor technology to inform diagnosis and treatment, 2) Managing symptoms by restoring cardiac output, electrophysiology, and hemodynamics, and often serving as bridge-to-recovery or bridge-to-transplantation strategies, and 3) Repairing damaged tissue, including myocardium and heart valves, when management strategies are insufficient. Each intervention approach and technology require specific material properties to function optimally, relying on materials that support their action and interface with the body, with new technologies increasingly depending on advances in materials science and engineering. This review explores material properties and requirements driving innovation in advanced intervention strategies for heart disease and highlights key examples of recent progress in the field driven by advances in materials research.

Teleoperated Navigation of a Robotically Steerable Guidewire under Fluoroscopy in a Flow Environment

A chronic total occlusion (CTO) is a complete blockage that impedes blood flow in the coronary artery. Minimally invasive procedures for treating CTOs typically involve manually steering a guidewire to the occlusion. However, navigating the guidewire throughout arteries can be challenging due to bifurcations and narrow vessels. This paper introduces a novel robotic guidewire design that is specifically engineered to navigate the aortic bifurcation, into peripheral branches of the right common iliac artery. We present a detailed description of the design and outline the procedure for determining the notch parameters to reduce motion coupling between the flexible joints. Lastly, we demonstrate remote control of the guidewire as it traverses through a phantom vasculature under different pulsatile flow rates to validate the feasibility of the guidewire.

Compact Design and Task Space Control of a Robotic Transcatheter Delivery System for Mitral Valve Implant

Mitral regurgitation (MR) is one of the most common valvular abnormalities, and the gold-standard for treatment is surgical mitral valve repair/replacement. Most patients with severe MR are over the age of 75, which makes open-heart surgery challenging. Thus, minimally invasive surgeries using transcatheter approaches are gaining popularity. This paper proposes the next generation of a robotic transcatheter delivery system for the mitral valve implant that focuses on the design of the actuation system, modeling, and task space control. The proposed actuation system is compact while still enabling bidirectional torsion, bending, and prismatic joint motion. A pulley structure is employed to actuate the torsion and bending joints using only one motor per joint in conjunction with an antagonistic passive spring to reduce tendon slack. The robotic transcatheter is also optimized to increase its stability and reduce bending deflection. An inverse kinematics model (with an optimization algorithm), singularity analysis method, and joint hysteresis and compensation model are developed and verified. Finally, a task space controller is also proposed. Experiments, including trajectory tracking and demonstrations of the robot motion in an ex vivo porcine heart and a phantom heart through a tortuous path are presented.

A multifunctional soft robot for cardiac interventions

In minimally invasive endovascular procedures, surgeons rely on catheters with low dexterity and high aspect ratios to reach an anatomical target. However, the environment inside the beating heart presents a combination of challenges unique to few anatomic locations, making it difficult for interventional tools to maneuver dexterously and apply substantial forces on an intracardiac target. We demonstrate a millimeter-scale soft robotic platform that can deploy and self-stabilize at the entrance to the heart, and guide existing interventional tools toward a target site. In two exemplar intracardiac procedures within the right atrium, the robotic platform provides enough dexterity to reach multiple anatomical targets, enough stability to maintain constant contact on motile targets, and enough mechanical leverage to generate newton-level forces. Because the device addresses ongoing challenges in minimally invasive intracardiac intervention, it may enable the further development of catheter-based interventions.

Telerobotic Transcatheter Delivery System for Mitral Valve Implant

Mitral regurgitation (MR) is the most common type of valvular heart disease, affecting over 2% of the world population, and the gold-standard treatment is surgical mitral valve repair/replacement. Compared to open-heart surgeries, minimally invasive surgeries (MIS) using transcatheter approaches have become popular because of their notable benefits such as less postoperative pain, shorter hospital stay, and faster recovery time. However, commercially available catheters are manually actuated, causing over-exposure of clinical staff to radiation and increased risk of human error during medical interventions. To tackle this problem, in this letter, we propose a telerobotic transcatheter delivery system, which consists of a robotic catheter (5.7 mm OD), a reinforced guide tube (1.11m length), and an actuation system. We present the robotic system design, fabrication of key components, and static model of reinforced quadlumen tube. The robot interface design enables the user to intuitively control the robot. We demonstrate the effectiveness of the telerobotic transcatheter delivery system and reinforced quadlumen tube in a realistic human cardiovascular phantom for preclinical evaluation.