Robotics-assisted catheter manipulation for improving cardiac ablation efficiency

The quality of contact between the catheter tip and cardiac tissue has been identified as an important factor in the efficacy of the catheter-based cardiac ablation procedures. However, maintaining a constant tip/tissue contact force during the procedure is difficult due to cardiac and respiratory motions. Robotic manipulation of the catheter has the potential to overcome this difficulty and decrease the range of variations in the contact force during the ablation procedure. This paper investigates the possibility of performing motion compensation for conventional steerable ablation catheters using a robotic manipulator. The behavior of such catheters is analyzed in free space as well as in contact with static and moving targets and the limitations in the actuation mechanism are identified. Based on this analysis, a technique for synchronizing the motion of the catheter tip with cardiac motion is proposed. The suggested control system estimates the frequency of the moving target and reshapes the input trajectory accordingly. The performance of the resulting system is evaluated experimentally. The results show that in the experimental setting, the proposed technique reduces the variations in the contact force and noticeably improves the quality of tip/tissue contact.