Abbott Laboratories announced Monday that the Food and Drug Administration has granted approval for a medical device called the HeartMate 3, which pumps blood for heart-failure patients with a fully magnetically levitated propeller that simulates the beating of a heart.
The device, which Abbott acquired earlier this year when it bought Minnesota-based St. Jude Medical, is supposed to be safer than traditional left-ventricular assist heart pumps because it eliminates friction and cellular damage created by rotors mounted on mechanical bearings. Clinical trial results published in February showed that after six months, HeartMate 3 patients lived with fewer strokes and device problems compared to those with Abbott's other heart pump.
"Heart failure is a crippling and costly disease and the HeartMate 3 system is a big stride forward in giving patients the opportunity to return to better quality lives," Dr. Mark Carlson, chief medical officer of Abbott's heart-failure business, said in a news release announcing the FDA approval.
The only other major competitor in the market for left-ventricular assist devices (LVADs) is Minnesota-run Medtronic. Monday's FDA approval news should give Abbott the edge in the market, according to cardiovascular device market analyst Fernando Amador, of the Toronto-based Decision Resources Group.
Abbott declined to talk about device prices. Amador said hospitals tend to pay about $80,000 apiece for LVADs, though exact figures vary and Abbott is likely to seek a premium price for the HeartMate 3.
The U.S. LVAD market is worth at least $400 million a year and is growing.
Wells Fargo Securities senior analyst Larry Biegelsen said in a note to investors that the HeartMate 3 should provide a boost to the overall U.S. market and help Abbott take market share from Medtronic because the device is smaller and has lower rates of complications in treating end stage heart failure.
Heart failure is a weakening of the heart muscle caused by persistent high blood pressure, heart attack, valve diseases, birth defects or other factors. Left untreated, the low blood flow from heart failure can damage other organs and eventually lead to death.
About 6 million Americans today live with heart failure with varying levels of severity, for which doctors typically prescribe drugs, physical exercise and diet changes. Implanted medical devices may be used on advanced cases that don't respond to treatment, and LVADs like the HeartMate 3 are the most complex options outside of a total artificial heart or human heart transplant.
A ventricular-assist device works by taking blood out of a damaged ventricle — usually the left ventricle — and pumping it into the aorta above the heart with enough force to improve a person's full-body circulation. Traditional LVADs, including Abbott's older HeartMate II device, use a propeller mounted on bearings inside the device to create the blood momentum.
But such propellers are vulnerable to a problem called "pump thrombosis," in which friction from the rotors and narrow passages in the device create blood clots that can cause mechanical damage and expose patients to a risk of stroke and re-operation to replace the clotted-up device.
The problem is considered so common that it has "lowered enthusiasm" for implanting the devices, according to a study report in the New England Journal of Medicine this past February.
The HeartMate 3 uses a propeller that is suspended in place using magnets instead of physical bearings that touch the rotor, reducing friction and shear stress on blood cells.
Although the device's propeller spins continuously, it changes speeds at regular intervals to simulate a pulse and further reduce the risk of clot formation.
"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," the NEJM study report said. "The incremental benefits associated with the centrifugal-flow pump observed in this 6-month analysis were due to the absence of suspected or confirmed pump thrombosis leading to surgical pump exchange or urgent transplantation."
The "Momentum 3" study found that none of the 152 HeartMate 3 patients wound up with pump thrombosis, while 14 of the HeartMate II patients had it after six months. Overall death rates were the same in both groups of advanced heart-failure patients, but those who were randomized to the HeartMate 3 had a higher combined rate of freedom from major stroke or device replacement than the group who got the older pump (86 percent vs. 77 percent).
For now, the HeartMate 3 is only approved as a "bridge to transplant" therapy, which means that it is intended to keep the patient alive long enough to get a heart transplant or total artificial heart. An Abbott Labs spokeswoman confirmed Monday that the Momentum 3 study is ongoing, with a goal of gathering data to support use for long-term "destination" therapy for patients who don't expect to get another heart.