All subjects will be followed in the study from the date of TAH-t implant until six months post-implant, cardiac transplantation, death, or withdrawal from study, whichever occurs first. Data from the six month post-TAH-t implant period will be used to support an HDE application. After the six month follow-up visit, patients will continue to be followed under the study for up to five (5) years post-TAH-t implant [every six months for up to two years while supported with the TAH-t implant and then annually for another three years].