Avoidance of aspirin as part of an antithrombotic regimen that includes vitamin K antagonists (VKAs) in patients with advanced heart failure (HF) treated and with fully magnetically levitated left ventricular assist devices (LVADs), is not inferior to a regimen containing aspirin, according to findings from the ARIES-HM3 trial presented Nov. 11 at AHA 2023 and simultaneously published in JAMA. Additionally, exclusion of aspirin did not increase thromboembolism risk and was associated with a reduction in bleeding events, said Mandeep R. Mehra, MBBS, FACC, who presented the findings.

ARIES HM3 enrolled 628 patients from 51 centers in nine countries who had advanced HF and a fully magnetically levitated LVAD and randomized them to an antithrombotic regimen that included aspirin (100 mg daily) or a placebo regimen with VKA therapy. Median follow-up was 14 months and 77% were men and approximately 33% were Black. The composite primary endpoint, assessed for noninferiority (−10% margin) compared with placebo, was survival free of a major nonsurgical hemocompatibility-related adverse events at 12 months. The primary secondary endpoint was nonsurgical bleeding events.

Of the 589 patients who were analyzed, more patients were alive and free of hemocompatibility events at 12 months in the placebo group (74%) compared with those taking aspirin (68%). Noninferiority of placebo was demonstrated (absolute between-group difference, 6.0% improvement in event-free survival with placebo; p<0.001). Additionally, a reduction in nonsurgical bleeding events was observed in the placebo group compared with the aspirin group, leading to decreases in bleeding-related hospitalization rates and costs of care.

“The benefits of avoiding aspirin are consistent among those with prior vascular disease, including surgical or percutaneous coronary revascularization, obesity, or diabetes, which are characteristics associated with increased thrombosis risk,” Mehra and colleagues said. “Aspirin is not required to maintain outcomes with a fully magnetically levitated LVAD in advanced HF, and exclusion from antithrombotic therapy is safe and associated with a reduction in bleeding events.”