The US Food and Drug Administration has approved Thoratec’s PMA (pre-market approval) supplement, allowing the use of its HeartMate II left ventricular assist system for destination therapy.
This approval means that the HeartMate II can be used to provide long-term cardiac support for patients suffering from advanced stage heart failure who are not eligible for transplantation. Thoratec said it will begin roll-out of the device for the destination therapy indication immediately and has sufficient inventory to address the expected increase in demand. The device was approved for bridge to transplantation in the USA under the original PMA in April 2008.
The approval allows the HeartMate II to be used in patients with New York Heart Association (NYHA) Class IIIB or IV end-stage left ventricular failure who have received optimal medical therapy for at least 45 of the last 60 days, and who are not candidates for cardiac transplantation. The PMA approval was based on a filing submitted in April 2009 that included two-year data on a pivotal study cohort of 200 randomised patients enrolled at 38 centres. Patients in the HeartMate II destination therapy trial were randomised to the HeartMate II or the HeartMate XVE – the only other device approved for destination therapy – on a 2:1 basis, respectively. Patients in the pivotal cohort ranged in age from 26–81 years old, with a median age of 64 years. Also included in the primary analysis were data on 24 small body surface area patients who because of their body size could not be randomised to the larger HeartMate XVE. The filing also included data on adjunctive cohorts totalling an additional 409 patients, including those who had been originally supported by a HeartMate XVE, and based on the need for device replacement, elected to receive a HeartMate II, as well as patients enrolled under continuous access protocols.
As a condition of the approval, Thoratec has agreed to a post-approval study of 247 patients who will be followed until outcome or two years, whichever occurs first. Thoratec will utilise the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) to collect the FDA-required data on outcomes, adverse events, functional status and quality of life. Thoratec has also agreed to conduct a second small study at three specific centers to collect data regarding the relationship between bleeding, thrombosis, von Willebrand syndrome and anticoagulation in left ventricular assist device patients.
The HeartMate II and the HeartMate XVE are the only devices approved by the FDA for both destination therapy and bridge to transplantation. A continuous flow device, the HeartMate II is an implantable left ventricular assist system powered by a rotary pumping mechanism and is designed to have a much longer functional life than pulsatile devices and to operate more simply and quietly. The device provides blood flow through the circulatory system on a continuous basis with only one moving part. It is also smaller and easier to implant than previously approved pulsatile devices.