Magnetic Ball Chain Robots for Cardiac Arrhythmia Treatment

TL;DR

Experimental validation shows that the ball chain can ablate heart tissue and generate lesions comparable to the current clinical ablation catheters, and smoother navigation is observed using the proposed robotic system.

Abstract

This paper introduces a novel magnetic navigation system for cardiac ablation. The system is formed from two key elements: a magnetic ablation catheter consisting of a chain of spherical permanent magnets; and an actuation system comprised of two cart-mounted permanent magnets undergoing pure rotation. The catheter design enables a large magnetic content with the goal of minimizing the footprint of the actuation system for easier integration with the clinical workflow. We present a quasi-static model of the catheter, the design of the actuation units, and their control modalities. Experimental validation shows that we can use small rotating magnets (119mm diameter) to reach cardiac ablation targets while generating clinically-relevant forces. Catheter control using a joystick is compared with manual catheter control. blue While total task completion time is similar, smoother navigation is observed using the proposed robotic system. We also demonstrate that the ball chain can ablate heart tissue and generate lesions comparable to the current clinical ablation catheters.

Figures (16)

• Figure 1: Schematic representation of ball chain magnetic catheter introduced in the left atrium by femoral access.
• Figure 2: Schematic representation of the magnetic navigation system for cardiac ablation.
• Figure 3: Description of magnetic ball chains. Applied field ($\mathbf{B}$) represented as a generic non-homogeneous vector field.
• Figure 4: Representation of the actuation method.
• Figure 5: Simulation results showing the alignment of the chain's tip with the applied magnetic field.