Thoratec Corporation develops, manufactures and markets medical devices used for mechanical circulatory support for the treatment of heart failure patients. The Company's products include ventricular assist devices (VADs), such as HeartMate II Left Ventricular Assist System (HeartMate II), HeartMate III Left Ventricular Assist System, Thoratec Paracorporeal Ventricular Assist Device (PVAD) and Thoratec Implantable Ventricular Assist Device (IVAD). For acute circulatory support, the Company's product lines are CentriMag Acute Circulatory System (CentriMag) and for pediatric patients PediMag/PediVAS Acute Circulatory System (PediMag/PediVAS). HeartMate III, a centrifugal-flow, chronic, left ventricular assist system.