Abstract 15203: MRI-Compatible Voltage-Based Electro-Anatomic Mapping in Swine Models: Verifying an Enabler for Efficient Multimodality Electrophysiology
Background: MRI provides luminal, edema & scar maps , which assist Electrophysiological (EP) interventions for treatment of ventricular & atrial arrhythmias. A voltage-based Electroanatomic Mapping (EAM) system, rendered MR compatible, may enable registration-free EP procedures to be performed partially in & outside the MRI; during X-ray, Intra-cardiac-echo (ICE) or EAM guidance.
Objectives: To perform multi-catheter EAM (localization & wall-ECG measurement) & navigation both in & outside the MRI scanner. To perform voltage-based positional tracking during MR imaging, improving catheter identification.
Methods: An MR compatible EnSite™ Velocity™ cardiac mapping system (St. Jude Medical) was constructed using MR compatible EP catheters, modified surface patches, MR safe transmission lines & switching circuits, preventing MR gradient-noise from reducing tracking accuracy . X-ray/ICE guided trans-septal puncture was performed on 5 intubated swine. The swine were moved to an MR suite equipped with the prototype system. Pre-procedural 3D ECG-gated MR Angiography served as navigational roadmaps. Two voltage-tracked deflectable EP catheters were used for navigation & EAM of the left & right heart inside MRI, with a third in the coronary sinus. Imaging was tested simultaneously with voltage-tracking. The swine were moved out of the magnet & navigation was continued without coordinate re-registration.
Results: Navigation was performed in & outside the MRI at >20 frames-per-second without re-registration. Intra-/extra-MRI positional change <3mm. Simultaneous imaging & tracking succeeded in MRI sequences with repetition-times>32ms, visualizing catheter surroundings during critical procedure stages.
Conclusions: MRI-compatible voltage tracking allows EP procedures in & outside MRI without re-registration. Ref:  CE Saikus JACC Img.‘09,  ZTH Tse ISMRM’12 Acknowledgement: NIH U41-RR019703, R43 HL110427-01, AHA 10SDG261039
- © 2012 by American Heart Association, Inc.