A medical device is configured to attenuate emission of electromagnetic radiation and comprises a housing, a circuit assembly mounted in the housing, and a panel coupled to the housing and to the circuit assembly. The panel comprises a first conductive region on an interior surface of the panel that is configured to be capacitively coupled to the ground, an opening substantially adjacent to the first conductive region, a second conductive region on the interior surface that is configured to be coupled to ground, and a non-conductive region on the interior surface between the first conductive region and the second conductive region.