Magnetically Levitated Rotor Helps Heart Pump Blood

A new left ventricle assist system (LVAS) levitates in the middle of the heart chamber, never touching the walls, consistently pushing blood from the heart to the body.

The DuraHeart LVAS is a third-generation rotary blood pump designed for long-term patient support. It incorporates a centrifugal flow rotary pump with a magnetically levitated impeller to pump blood from the heart around the body. The magnetically levitating impeller--shaped like a flat magnetic disc the size of hockey puck--acts as a paddlewheel, turning constantly as it is suspended in a magnetic field coupled to a turning motor within the pump housing. This expels the blood into a flexible artificial blood vessel, called the outflow conduit, which is connected to the ascending aorta. As a result, the DuraHeart may cause less damage to blood cells and be less likely to allow dangerous blood clots to form, compared with other heart-assisting devices that use mechanical pumps. During the implantation procedure, the surgeon diverts blood flow from the ailing left ventricle of the heart into a titanium tube that leads into the pumping chamber. The DuraHeart a product of Terumo Heart (Ann Arbor, MI, USA), has received the European Community (EC) marking, and is currently undergoing clinical trails in the United Sates.

"This trial will test the DuraHeart's potential to overcome some of the issues that have been seen with other devices, including hemolysis caused by shear stress on red blood cells, and clotting risk caused by blood that does not circulate rapidly enough from all areas of the chamber,” said surgeon Francis Pagani, M.D., Ph.D. of the University of Michigan (Ann Arbor, MI, USA) cardiovascular center, who is co-leader of the U.S. clinical trial of the DuraHeart. "It also remains to be seen if this device offers superior durability, which might make it useful as a destination therapy that could remove the need for a heart transplant.”

Related Links:
Terumo Heart
University of Michigan