on March 6, 2009
Published online before print March 6, 2009, doi: 10.1161/CIRCEP.108.778357
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Original Article |
Feasibility of Real Time Magnetic Resonance Imaging with a Novel Carbon Catheter for Interventional Electrophysiology
1 University of Würzburg;
2 Research Center Magnetic-Resonance-Bavaria;
3 Massachusetts General Hospital, Harvard Medical School;
4 Biotronik GmbH & Co. KG, Berlin
5 E-mail: ritter_o{at}medizin.uni-wuerzburg.de
Background—Cardiac magnetic resonance imaging (MRI) offers 3D real time imaging with unsurpassed soft tissue contrast without X-ray exposure. To minimize safety concerns and imaging artifacts in MR guided interventional EP, we aimed at developing a setup including catheters for ablation therapy based on carbon technology.
Methods and Results—The setup, including a steerable carbon catheter, was tested for safety, image distortion, and feasibility of diagnostic EP studies and radiofrequency ablation at 1.5 Tesla. MR imaging was performed in three different 1.5-T whole-body scanners using various receive coils and pulse sequences. To assess unintentional heating of the catheters by radio frequency (RF) pulses of the MR scanner in vitro, a fluoroptic thermometry system was used to record heating at the catheter tip. Programmed stimulation and ablation therapy was performed in eight pigs. There was no significant heating of the carbon catheters while using short, repetitive RF pulses from the MR system. Since there was no image distortion when using the carbon catheters, exact targeting of the lesion sites was possible. Both atrial and ventricular RF-ablation procedures including AV node modulation were performed successfully in the scanner. Potential complications such as pericardial effusion after intentional perforation of the RV free wall during ablation could be monitored in real time as well.
Conclusion—Here we describe a newly developed EP technology for interventional electrophysiology based on carbon catheters. The feasibility of this approach was demonstrated by safety testing and performing EP studies and ablation therapy with carbon catheters in the MRI environment.
Key Words: ablation • electrophysiology • magnetic resonance imaging
Author contributions: Peter Nordbeck, MD, and Wolfgang R Bauer, MD, PhD contributed equally to this work.