Platelet activation and aggregation in different centrifugal-flow left ventricular assist devices

Area of Science:

• Cardiovascular Medicine
• Biomedical Engineering
• Hematology

Background:

• Left-ventricular assist devices (LVADs) are crucial for end-stage heart failure management.
• Two centrifugal-flow LVADs, HeartMate 3 (HM3) and Medtronic/Heartware HVAD (HVAD), are approved.
• Differences in thrombogenicity between HM3 and HVAD warrant investigation.

Purpose of the Study:

• To compare platelet activation and aggregation markers between HM3 and HVAD systems.
• To investigate potential differences in von Willebrand factor (VWF) profiles between the two LVADs.

Main Methods:

• Prospective study of 59 LVAD patients (40 HM3, 19 HVAD).
• Flow cytometry assessed P-selectin, GPIIb/IIIa, and monocyte-platelet aggregates (MPA).
• Light-transmission aggregometry (LTA) and multiple-electrode aggregometry (MEA) measured platelet aggregation.
• VWF antigen (VWF:Ag), VWF activity (VWF:Ac), and VWF multimer patterns were analyzed.
• Soluble P-selectin (sP-selectin) was measured via ELISA.

Main Results:

• In vivo and agonist-stimulated platelet activation markers (P-selectin, GPIIb/IIIa, MPA) were similar between HM3 and HVAD.
• Platelet aggregation measured by LTA and MEA did not differ significantly between the two LVAD groups.
• VWF:Ag and FVIII:C levels were comparable, but HVAD patients exhibited significantly lower VWF:Ac and reduced large VWF multimers.
• Soluble P-selectin levels were similar in both LVAD groups.

Conclusions:

• On-treatment platelet activation and aggregation are comparable between HeartMate 3 and HVAD left-ventricular assist device patients.
• Observed differences in von Willebrand factor activity and multimer profiles between HVAD and HM3 require further clinical investigation.
• Future trials should explore the clinical implications of these VWF differences in LVAD thrombogenicity.