An implantable medical device includes a housing. An opening is present in the housing. The implantable medical device includes an antenna in the housing, where the antenna is located below the opening. The implantable medical device includes a cover coupled to edges of the housing defining the opening to close the opening. The cover enables passage of radio frequency signals at one or more communication frequencies to and from the antenna. The implantable medical device also includes an antenna shield positioned above the cover. The antenna shield reduces passage of radio frequency signals to and from at least a portion of the antenna during use.