Abstract: The implantable medical device includes high-voltage components (such as defibrillation shock generation components) operative to generate high-voltage pulses for delivery to tissues of the patient while using the case or housing of the device as a stimulation electrode. The device also includes low-voltage Medical Implant Communication Service (MICS) or Medical Device Radiocommunications Service (MedRadio) components operative to generate low-power signals for communicating with an external device via radio frequencies while using the case as part of an antenna. A conductive noise shield is mounted within the case of the device and interposed between the high-voltage components and the case, with the shield configured to attenuate electrical interference between the high-voltage components and the case to facilitate radio-frequency communication between the low-voltage MICS/MedRadio components and the external device, which use the case as part of the antenna.