RF induced heating is a principal concern for patients with active implantable medical devices (AIMDs). MRI exams at >1.5T are often avoided, largely because the SAR increases with the square of field strength, thus RF-induced heating is expected to increase. RF induced heating, however, also arises because of the antennae-like characteristics of the AIMD. Our objective was to compare RF-induced heating in rods with different lengths at 1.5T and 3T when the same B1+RMS was applied. Results suggest that for a specific device length, RF-induced heating is not always higher for increasing field strength.