A feedthrough terminal assembly for an active implantable medical device (AIMD) includes magnetic shielding elements to block incident magnetic fields during medical procedures such as Magnetic Resonance Imaging. The assembly includes conductive or ground plate(s) embedded in an insulator surrounding elements of the assembly, a plurality of lead wires extending from electronic circuitry of the AIMD, and a lossy ferrite inductor through which the lead wires extend in non-conductive relation for increasing the impedance of the lead wires at selected RF frequencies. Alternatively, the assembly includes a conductive sleeve or cap surrounding the feedthrough capacitor and/or conductive support.