December 2, 2016 – A Fully Magnetically Levitated Circulatory Pump for Advanced Heart Failure
A scarcity of effective therapeutic options for advanced heart failure has led to the development of durable mechanical circulatory support devices. Left ventricular assist devices, more accurately known as left ventricular assist systems, increase the rate of survival and improve quality of life among patients with advanced heart failure. However, these clinical benefits are balanced by an increased risk of infection, bleeding, neurologic events, and pump malfunction that is due principally to pump thrombosis.
As adoption of circulatory pumps has expanded, concerns about pump thrombosis have heightened. In 2013, two reports suggested that there has been an increase in the risk of pump thrombosis, beginning in 2011, associated with a currently approved axial continuous-flow pump, HeartMate II. Pump thrombosis has also been associated with an approved centrifugal continuous-flow pump, HeartWare. The need for surgical pump exchange due to pump thrombosis results in substantial complications and increased cost of care. These concerns have lowered enthusiasm for expansion of this therapy to patients who are less severely ill and have even led to the premature discontinuation of a clinical trial.
A new fully magnetically levitated centrifugal continuous-flow circulatory pump, HeartMate 3, has been engineered to reduce shear stress on blood elements and avert pump thrombosis. This pump has wide blood-flow passages and no mechanical bearings, is frictionless, and is programmed to facilitate rapid changes in rotor speed to create an intrinsic artificial pulse. This fixed pulse, which is asynchronous with the native heartbeat, reduces stasis in the pump.
We conducted a trial to compare clinical outcomes with the centrifugal-flow pump HeartMate 3 with outcomes with the axial-flow pump HeartMate II in patients with advanced heart failure that is refractory to standard medical therapy. In this report, we present the results of the first prespecified analysis of the trial.