The newer HeartMate 3 continuous-flow left ventricular assist device (LVAD) improved on its predecessor in staving off neurological complications among implanted patients, long-term results from the MOMENTUM 3 trial showed.
Stroke rates were 10.1% and 19.2% in the first 2 years following placement of the HeartMate 3 and HeartMate II devices, respectively (P=0.02), reported Paolo Colombo, MD, of the Columbia University Medical Center in New York City, and colleagues, in
With no difference in event rates in the first 180 days, it was only thereafter that the newer device was associated with significantly fewer strokes (0.04 versus 0.13 per patient-year, OR 0.23, 95% CI 0.08-0.63), according to the report, which was also presented as a late-breaking trial at the Heart Failure Society of America conference.
The sole predictor of having fewer strokes in the long run: treatment with the HeartMate 3 pump (adjusted OR 0.44, 95% CI 0.24-0.82). Investigators could not reach any conclusions on whether blood pressure and antithrombotic medications affect stroke.
"Overall, our findings indicate that the difference in stroke events that we found in the MOMENTUM 3 trial is primarily device related, owing dominantly to the enhanced hemocompatibility observed with the HeartMate 3 pump, rather than influenced by preimplantation or postimplantation factors," the authors said.
The main upgraded feature of HeartMate 3 is its centrifugal-flow pump (as opposed to HeartMate II's cardiac axial-flow one).
That neither blood pressure nor antithrombotic regimens appeared to budge the risk of stroke "likely reflects the superior hemocompatibility of the HeartMate 3," said Randall Starling, MD, of Cleveland Clinic, one of the participating centers.
Included in this prespecified secondary analysis of the MOMENTUM 3 trial were the first 361 patients with advanced heart failure who got their assigned device. Participants were eligible whether they got mechanical circulatory support as a bridge to transplantation or destination therapy.
During the study, all stayed on anticoagulation with warfarin (target international normalized ratio 2.0-3.0) and aspirin.
One important finding from the study was that patients experiencing any kind of stroke -- hemorrhagic (43%), ischemic (57%), disabling (51%), or nondisabling (51%) -- had lower 2-year survival rates than the 85% of those who didn't have a stroke.
"These findings also suggest that clinical trials of LVAD therapy must not selectively report functionally disabling stroke rates; rather, they must primarily consider overall stroke rates because of the similar prognostic implications of nondisabling and disabling strokes," Colombo's group suggested.
As for the relatively small sample in this study, the investigators noted that the full 1,000-person MOMENTUM 3 cohort will have long-term stroke data reported within a year from now.
"I also expect the standard of care in the trial was excellent and more uniform than perhaps in real-world practice," Starling commented.
Disclosures
The MOMENTUM 3 trial was sponsored by Abbott.
Colombo disclosed support from, and a relevant relationship, with Abbott.
Primary Source
Circulation
Colombo PC, et al “Comprehensive analysis of stroke in the long-term cohort of the MOMENTUM 3 study: A randomized controlled trial of the HeartMate 3 versus the HeartMate II cardiac pump” Circulation 2018; DOI:10.1161/CIRCULATIONAHA.118.037231.