Thrombocytopenia Complicating Transcatheter Aortic Valve Implantation: Differences Between Two New-Generation Devices

Area of Science:

• Cardiovascular Medicine
• Hematology
• Biomaterials Science

Background:

• Thrombocytopenia is a common and detrimental complication following transcatheter aortic valve implantation (TAVI).
• Previous observations indicated a more significant platelet reduction in patients receiving the Portico TAVI device compared to the Evolut device.

Purpose of the Study:

• To investigate periprocedural platelet damage and the pro-inflammatory state in TAVI recipients.
• To explore the potential role of the TAVI device storage solution and biomaterial in platelet injury and immune activation.

Main Methods:

• Retrospective analysis of 64 TAVI recipients (Portico vs. Evolut).
• Assessment of platelet damage using annexin V staining.
• Evaluation of monocyte-phagocytic phenotype via CD14/CD36 expression.
• Measurement of serum cytokines (IL-6, IL-8) in a subset of patients.

Main Results:

• Portico recipients exhibited a more profound platelet drop and increased platelet damage compared to Evolut recipients.
• An additional flushing step for the Portico valve mitigated thrombocytopenia, platelet damage, and CD36-monocyte counts.
• Elevated serum IL-8 levels, a thrombocytopenia inducer, were specifically observed in Portico recipients, even after extra rinsing.

Conclusions:

• The storage solution of the Portico TAVI valve may induce platelet injury.
• Biomaterial interaction with innate immunity is hypothesized to contribute to TAVI-associated thrombocytopenia.
• Further large-scale prospective studies are warranted to confirm these findings.