Antonitsa Vlahoulis knew as she slipped into unconsciousness on the operating room table that her surgeon would choose which medical device she would receive to fix her leaky heart valve. But when a warranty card arrived in the mail for the device stitched into her heart, Vlahoulis got the first of several shocks. The card referred to the device by its original name: the McCarthy Annuloplasty Ring. That's when she realized that Dr. Patrick McCarthy, her surgeon at Northwestern Memorial Hospital, had invented it. Vlahoulis, of Niles, said McCarthy had told her he would choose a ring from those listed in a booklet he gave her. She flipped through it, but this ring wasn't there. She checked the Food and Drug Administration's website, looking for the ring on the agency's list of approved devices. But she couldn't find it. When she contacted the FDA to ask about it, she received a startling email in reply.