Sascha Krueger1, Oliver Lips1,
Bernd David1, Steffen Weiss1
1Philips Research
Laboratories,
MR-guided electrophysiology (MR-EP) ablation procedures for treatment of arrhythmias have the potential benefit of visualizing the tissue response and improving catheter guidance. Effective measures to ensure RF safety of diagnostic MR-EP catheters have been proposed, including the use of active tracking via transformer-based cables and recording of intra-cardiac ECG via highly resistive (HR) wires. Providing trans-catheter ablation power transmission and tissue impedance measurement functionality RF-safely remains a major challenge. This work shows the initial evaluation of a broad-band, high-power transmission line for RF safe ablation and tissue impedance measurements based on a novel concept. The proposed ablation line is designed for integration with state-of-the-art tip-irrigated catheters and utilizes the irrigation liquid for cooling of a thin PCB-based cable consisting of many resonant trap circuits floating in the irrigation tube. It is shown that tip heating is eliminated and that the capacitors and inductors of trap circuits are effectively cooled by the irrigation liquid, so that local temperature elevations can be avoided completely over the entire length of the catheter.