Minimally-invasive procedures have become increasingly popular for screening, diagnosis and surgery. One of the most commonly performed procedures is catheter ablation for cardiac arrhythmia. Cardiac arrhythmia is a group of conditions abnormal heart rhythm in which the electrical activity of the heart is irregular or i faster or slower than normal. Through catheterized ablation procedures, abnormal cardiac tissues that cause irregular heartbeats can be destroyed. It is well known that contact force of the ablation tip is one of the critical factors of energy delivery that determine the lesion size ad ablation time during the procedure. If the contact force is too low, the ablation will take too lon to burn the target tissue. If the force is too high, a risk of perforation is introduced. To addres this issue, various tip force-sensing technologies have been proposed and have recently become commercially available. However, these technologies provide only contact force measurement during ablation but do not allow any automatic capability of force control, resulting in manually controlled procedure by the operator. Therefore, development of automatic force control along with accurate tip force sensing will be an innovation that could be applicable to all catheter ablation procedures in the future. The goal of this project is to develop an automatic force control system for cardiac ablation catheters. The innovation in the proposed system consists of a novel design incorporating a micro-actuator located at the tip of an ablation catheter for contact force control, combined with multiple embedded fiber-optic strain sensors that detect a multi-axis tip force in real-time.
Specific aims i nclude i) design and fabrication ofa ablation catheter prototype with an embedded force control unit that applies linear displacement and force to the target tissue with an accurate measurement of tip force, ii) design and prototyping of an anchor mechanism that mechanically holds the force control unit to the target site for increased control performance, iii) development of contact force control algorithms with modeling and system identification, and iv) validation experiments of the catheter prototype using phantom heart models that simulate dynamic heart function, and ex-vivo animal heart tests. The design and prototyping process as well as validation experiments will be monitored and guided by a cardiology expert through the entire project period. Successful completion of this research will demonstrate the feasibility of this research and support follow-on R01 application for developing a further improved system with more clinical tests.
This project increase the safety and efficiency of all catheter ablation procedures and also other minimally invasive procedures by addressing issues of i) risk of procedural complications from lack of dexterity in controlling interventional/surgical tools, ii prolonged procedure time caused by not optimally designed procedures, and iii) patient discomfort by multiple revisions of procedures. Consequently, the successful results of this research will extend the health life of human by minimizing unnecessary clinical procedures.
Aranda-Michel, Edgar; Yi, Jaehyun; Wirekoh, Jackson et al. (2018) Miniaturized Robotic End-Effector with Piezoelectric Actuation and Fiber Optic Sensing for Minimally Invasive Cardiac Procedures. IEEE Sens J 18:4961-4968 |