HeartMate 3: ‘A Much More Forgiving Pump’

NEW ORLEANS — The HeartMate 3 left ventricular assist device’s (LVAD) safety and outcome advantage over its predecessor held up in the final analysis of the MOMENTUM 3 trial.

With the full complement of 1,028 advanced heart failure patients, the newer centrifugal-flow pump improved 2-year survival free of safety endpoint events (disabling stroke or reoperation to replace or remove a malfunctioning device) by a relative 16% compared with HeartMate II (76.9% vs 64.8%, P<0.001 for superiority).

Pump replacement as a secondary endpoint also remained significantly lower than with the older, axial flow device (12 patients vs 57, 2.3% vs 11.3%, RR 0.21), Mandeep Mehra, MD, of Brigham and Women’s Hospital in Boston, reported here at the American College of Cardiology meeting and simultaneously in the New England Journal of Medicine.

The findings were in line with 2-year data reported from an analysis of the first 366 patients, which likewise showed superiority over the HeartMate II for the composite primary endpoint (79.5% vs 60.2%) and reoperation for pump malfunction (1.6% vs 17.0%).

While that earlier analysis had showed no pump thrombosis requiring replacement with HeartMate 3, the lower rate in final results was still notable (1.4% vs 13.9%, P<0.001), Mehra said at a press conference for the late-breaking clinical trial session.

For every 100 patients implanted, 20 strokes, 22 pump thrombosis incidents, and 68 bleeds (38 GI) are prevented, Mehra summarized.

“We now have a much more forgiving pump in the left ventricular assist device space,” he concluded, predicting it would open up greater use.

Notably, the stroke rate was 48% lower with HeartMate 3 (9.9% vs 19.4%), with a 36% reduction in disabling stroke as well (5.0% vs 7.5%). In the previous analyses, only a nondisabling stroke reduction had been seen.

Bleeding overall and GI bleeds specifically were both 36% reduced compared with the prior-generation device. Mehra attributed this to the switch to a magnetically-levitated pump that reduces shear stress on blood cells and permits pulsatile flow.

“There wasn’t a mortality benefit, but if you start piling up additional procedures, hospitalizations, things like that, it’s clear that this magnetically triggered device is an advance,” Kim Eagle, MD, of the University of Michigan in Ann Arbor, commented in an interview with MedPage Today. “It’s changing practice right now.”

Too few LVADs have been implanted compared to the need, whether due to concern about cost or about complications, Clyde Yancy, MD, of Northwestern University in Chicago, told MedPage Today.

“Patients are beginning to thrive with these pumps. For a long time, we knew pumps could help patients to stay alive longer, but the whispered undercurrent was ‘alive but’ dealing with longitudinal complications,” he said. “Quality of life data may be the most important thing we saw.”

MOMENTUM 3 included advanced-stage heart failure patients who were candidates for an LVAD either as a bridge to transplantation or as destination therapy. Exclusion criteria included expectation of needing biventricular circulatory support, irreversible end-organ dysfunction, and active infection.

The trial showed a significant 8% relative reduction in all-cause rehospitalization, with a median 5 fewer days in-hospital.

Press conference panel discussant Gurusher Panjrath, MD, of George Washington University Hospital in the nation’s capital, pointed to the high survival rate at 2 years in comparison with transplant survival rates.

The next step is to pause and think how to go further with LVADs, he said. “Can we go for a lower risk population?”

last updated 03.18.2019