Updated LVAD yields fewer adverse events in patients with HF

Patients who received a new-generation left ventricular assist device experienced fewer hemocompatibility-related clinical adverse events compared with those implanted with an older device, according to new findings.

The HeartMate 3 (Abbott Laboratories) had updated engineering compared with the HeartMate II, including a frictionless motor, an artificial pulse to prevent pump stasis and wide gaps between the casing and rotor for blood paths, according to the study background.

To compare both devices, researchers performed a secondary endpoint evaluation of data from 289 patients with advanced-stage HF from the MOMENTUM 3 trial. Results were presented at the International Society for Heart and Lung Transplantation Annual Meeting and Scientific Sessions and published in Circulation.

Patients were previously assigned HeartMate 3 (n = 151; mean age, 64 years; 79% men) or HeartMate II (n = 138; mean age, 61 years; 80% men). The primary endpoint was survival free of reoperation to repair or replace the device and disabling stroke at 6 months and 2 years after implantation. Hemocompatibility-related clinical adverse events were also reviewed, including nonsurgical bleeding after 30 days, arterial thromboembolism, pump thrombosis, and stroke or other neurological events.

A hemocompatibility score system was designed, which evaluated each adverse event to calculate the total net burden. One point was given to mild events, and up to four points were given for more serious events. Each patient’s score was calculated during 6-month follow-up.

“The hemocompatibility risk score that we developed is based on a hierarchal approach,” presenter Nir Uriel, MD, professor of medicine and director of heart failure, transplant and mechanical circulatory support at the University of Chicago, told Cardiology Today. “A patient that has two [gastrointestinal] bleeding events is different than a patient that has a disabling stroke, and we should not look at any one of those adverse events as equal rather than hierarchal ... With this tiered approach, we studied the patient experience.”

Patients assigned the HeartMate 3 had significantly higher rates of survival free from hemocompatibility-related clinical adverse events (69 ± 4%) vs. those assigned the HeartMate II (55 ± 4%; HR = 0.62; 95% CI, 0.42-0.91).

At least one adverse event occurred in 43 patients (28%) with the HeartMate 3 compared with 53 patients (38%; P = .08) with the HeartMate II. The HeartMate 3 group mainly experienced bleeding events, whereas the HeartMate II group experienced more bleeding and thromboembolic events.

“We also identified that the intention to implant, if it was [bridge to transplant] or [destination therapy], were not important as findings to identify patients’ risk to be alive and without hemocompatibility adverse events,” Uriel told Cardiology Today.

The HeartMate 3 group yielded better hemocompatibility scores for nondisabling strokes (6 vs. 24; P = .026), medically managed pump thrombosis (0 vs. 5; P =.02) and surgically managed pump thrombosis (0 vs. 36; P < 001). The overall hemocompatibility score for those assigned the HeartMate 3 was 101 points (0.67 ± 1.5 points per patient; median, 0 points per patient; range, 0-10) vs. 137 points for patients assigned the HeartMate II (0.99 ± 1.79 points per patient; median, 0 points per patient; range, 0-9; OR = 0.64; 95% CI, 0.39-1.03).

“I would be really eager to see the results coming up on long-term support,” Uriel said in an interview with Cardiology Today. “This was the first 6 months of support. I want to see what will happen when those patients are 2 years on support, 3 years on support. Today, our expectation is that people will be able to live 5 or 6 years of support and even more. The question: what happened to the hemocompatibility-related adverse event burden? Is it going up? Is it going down? Is it plateauing? And is there a time that they’re in more risk? Time that they’re in less risk? And eventually, what kind of intervention can we do in order to reduce the hemocompatibility-related adverse event? This is our goal, to take those adverse events and to reduce them eventually so patients enjoy and benefit more from this technology.” – by Darlene Dobkowski

References:

Uriel N, et al. Oral Session 13: Contemporary LVAD trials — Same old song or different tune? Presented at: International Society for Heart and Lung Transplantation Annual Meeting and Scientific Sessions; April 5-8, 2017; San Diego.

Uriel N, et al. Circulation. 2017;doi:10.1161/CIRCULATIONAHA.117.028303.

Disclosure : The study was funded by Abbott Laboratories. Uriel reports serving as national principal investigator for the present study sponsored by Abbott, and receiving grants and consulting for Abbott and Medtronic.