NATIONAL HARBOR, MD. – A next-generation left-ventricular assist device, the HeartMate 3, gave a solid debut performance in an uncontrolled series of the first 50 recipients, which was designed to gain the device CE mark approval in Europe.
In this study, run at 10 sites in Australia, Austria, Canada, Czech Republic, Germany, and Kazakhstan, the new-design left ventricular assist device (LVAD) numerically surpassed the study’s prespecified primary endpoint with 6-month recipient survival of 92%. This bested the target survival rate of 88% that the trial’s designers derived from the survival rate among 50 matched patients who had received a LVAD during 2012-2014 and had entered the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS), Dr. Ivan Netuka said at the annual meeting of the Heart Failure Society of America.
Mitchel L. Zoler/Frontline Medical News
Dr. Ivan Netuka
Other notable findings of the HeartMate 3’s performance in the first 50 patients followed for 6 months were no pump malfunctions, no thrombosis within the pump, and no evidence of hemolysis, said Dr. Netuka, deputy director of cardiovascular surgery at IKEM hospital in Prague.
HeartMate 3 features several improvements over the HeartMate II model, such as a fully magnetically levitated rotor designed to eliminate friction and wear within the pump. The device also is engineered to produce an artificial pulse of 30 beats per minute, and it can deliver a wide blood-flow range of 2-10 L/min. Larger and consistent pump gaps are designed to reduced shear stress on blood components.
The study enrolled patients during June-November 2014 with NYHA class IIIB or IV heart failure and stage D heart failure, with a left ventricular ejection fraction of 25% or less. The 50 patients averaged 59 years of age and 90% were men; they were divided about equally between patients who received the device as a bridge to transplant and those who received the LVAD as destination therapy.
During 6 months of follow-up, two patients received a heart transplant. Twenty-one (42%) of the enrolled patients classified as INTERMACS patient profile 3, 20 (40%) as profile 4, and 5 (10%) as profile 2 patients, with the remaining four patients falling into other profile levels. Twenty-one patients had concomitant heart surgery when they received their LVAD, usually valve replacement. All patients received warfarin treatment and aspirin following device placement. Dr. Netuka and his associates calculated an expected 6-month survival of 78% for the enrolled patients without LVAD intervention.
The four deaths included a patient who died from cardiac arrest following a stroke on day 19 – a complication judged attributable to the device-placement procedure, a patient with circulatory failure on day 48, a suicide on day 113, and a patient with multiorgan failure on day 144.
After 6 months of follow-up, notable adverse events included bleeding in 19 patients (38%) – including gastrointestinal bleeds in 4 patients (8%) – strokes in 6 patients (12%), and infections in 18 patients (36%). Most of the adverse events occurred in the first 7 days following LVAD placement. Three of the six strokes were judged procedure associated, Dr. Netuka said.
Following device placement, patients showed improvements in their NYHA class and quality of life; their 6-minute walk distance improved by an average of 231 m.
The HeartMate 3 device is currently undergoing U.S. assessment in comparison to HeartMate II prior to submission to the Food and Drug Administration. The randomized trial, known as MOMENTUM 3, plans to enroll 1,028 patients with completion scheduled for 2018.
The study was sponsored by Thoratec, which is developing the HeartMate 3 device. Dr. Netuka is a speaker for and consultant to Thoratec.
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