Thoratec Corp. develops, manufactures and markets proprietary medical devices used for circulatory support for the treatment of heart failure patients. The company's products include Ventricular Assist Devices, HeartMate Left Ventricular Assist System, HeartMate II Left Ventricular Assist System, Thoratec Paracorporeal Ventricular Assist Device and Thoratec Implantable Ventricular Assist. It also manufactures and markets the CentriMag Acute Circulatory System, HeartMate II, PVAD, IVAD and for pediatric patients PediMag/PediVAS Acute Circulatory System. Its ventricular assist devices products primarily serve patients suffering from late-stage heart failure. Heart Failure is a chronic disease that occurs when degeneration of the heart muscle reduces the pumping power of the heart, causing the heart to become too weak to pump blood at a level sufficient to meet the body's demands. The company operates its business through the Cardiovascular group segment, which develops, manufactures mechanical circulatory products to support the cardiovascular systems of humans and to provide product-related services. Thoratec was founded in March 1976 and is headquartered in Pleasanton, CA.