Effect of aspirin dose on hemocompatibility-related outcomes with a magnetically levitated left ventricular assist device: An analysis from the MOMENTUM 3 study

Background: Aspirin (ASA) anti-platelet therapy is mandated with left ventricular assist devices (LVADs) to prevent hemocompatibility-related adverse events (HRAEs). However, the optimal dose of ASA with HeartMate 3 (HM3) LVAD is unknown. Methods: In an exploratory analysis of HM3-supported patients in the MOMENTUM 3 study (NCT02224755), 2 groups were analyzed: usual-dose (325 mg) and low-dose (81 mg) ASA with anti-coagulation targeted to an international normalized ratio of 2.0 to 3.0. Exclusion criteria included patients not receiving either ASA 81 mg or 325 mg, those with HRAEs ≤7 days after device implantation, and those receiving >1 anti-platelet agent. The primary end-point was survival free from HRAEs (non-surgical bleeding, pump thrombosis, stroke, and peripheral arterial thromboembolic events) at 2 years. Results: Overall, 321 HM3 patients (usual-dose: n = 141, low-dose: n = 180) were included in this analysis. Usual-dose group patients were younger (57 ± 13 vs 60 ± 12 years, p = 0.035) and less often assigned destination therapy (55% vs 67%, p = 0.029) than low-dose ASA. At 2 years, a similar proportion of patients in the usual- and low-dose groups (43.4% vs 45.3%, p = 0.94) met the primary end-point. There were no differences in survival free from hemorrhagic (usual-dose: 54.4% vs low-dose: 51.7%, p = 0.42) or thrombotic (usual-dose: 76.8% vs low-dose: 75.7%, p = 0.92) events. Conclusions: Usual- and low-dose ASA revealed similar rates of bleeding and thrombotic events in HM3 LVAD-supported patients within the MOMENTUM 3 trial. Whether ASA therapy provides any meaningful therapeutic effect in patients treated by the HM3 LVAD remains to be determined.