A novel cumulative transfer function concept for accurate prediction of RF heating of bipolar leads

Motivation: Radiofrequency (RF) tissue heating is a known safety risk for patients with cardiac implantable electronic devices (CIEDs), especially children with epicardial systems. Goal(s): We present the first cumulative transfer function based on the guidelines in ISO/TS 10974 to evaluate the RF heating of a CIED with a bipolar epicardial lead. Approach: We measured, calibrated, and validated cumulative transfer functions for predicting RF heating through in vitro experiments and electromagnetic simulations. Results: Our cumulative transfer functions accurately predicted RF heating around the electrode ends for 48 unique lead trajectories (r=0.90-0.97, p<0.05). Impact: We introduce a high-fidelity cumulative transfer function model of a CIED with a bipolar epicardial lead to enable the evaluation of RF heating of bifurcating leads during MRI.