For the first time, the fully mechanical heart made by BiVACOR, which uses the same technology as high-speed rail lines, has been implanted inside a human being. The feat marks a major step in keeping people alive as they wait for heart transplants.The total artificial heart (TAH) was implanted as part of an early feasibility study overseen by the US Food and Drug Administration. According to a statement from the Texas Heart Institute where the implantation surgery was carried out, the heart "is...