Characterization of the Relationship Between MR-Induced Distal Tip Heating in Cardiac Pacing Leads and the Electrical Performance of Novel Filtered Tip Assemblies

Robert S. Johnson¹, Holly Moschiano¹, Robert Stevenson¹, Scott Brainard², Sam Ye², Joseph E. Spaulding¹, Warren Dabney¹

The impedance of inductor-capacitor band stop filters were characterized with impedance spectroscopy. If was found the impedance of the device was controllable with proper selection of the inductor and capacitor values. The filters were incorporated in implantable leads and the temperature rise of the distal end was measured during a MRI scan with an RF-intensive imaging protocol. The minimum heating was 9C with the highest impedance filter and the maximum heating was 51C with a control lead. Systematic changes in the lead configuration and location reduced the heating to near instrumentation noise level.