Preprocedural P2Y₁₂ inhibition and decrease in platelet count following transcatheter aortic valve replacement

Background: Thrombocytopenia after transcatheter aortic valve replacement (TAVR) is associated with adverse clinical outcomes. Whether preprocedural P2Y₁₂ inhibition prevents postprocedural thrombocytopenia is uncertain. Methods: This retrospective analysis identified consecutive patients (n = 266) undergoing TAVR between November 2016 and July 2017. Preprocedure clopidogrel load ≥300 mg or maintenance P2Y₁₂ inhibitor therapy defined preprocedural P2Y₁₂ inhibition. Patients who did not consent for the registry (n = 8), with baseline severe thrombocytopenia (<90 × 10³ platelets/μL; n = 14), or without baseline platelet count (n = 4) were excluded. The primary outcome was proportion of patients who developed >20% decrease in platelet count from baseline to day 1 post-TAVR. Results: Patients with (n = 134) versus without (n = 106) preprocedural P2Y₁₂ inhibition had no differences in platelet count at baseline. Patients with preprocedural P2Y₁₂ inhibition had a significantly lower proportion of the primary outcome (34.3% vs. 57.5%, p =.001) and a lower absolute decrease in platelet count (32.8 × 10³ vs. 45.8 × 10³ platelet/μL, p =.01). Of patients without baseline thrombocytopenia (n = 198), a numerically lower rate of patients with versus without preprocedural P2Y₁₂ inhibition developed thrombocytopenia on day 1 post-TAVR (25.5% vs. 36.4%, p =.1). Conclusion: Patients who received preprocedural P2Y₁₂ inhibition prior to TAVR were less likely to demonstrate a decrease in platelet count after TAVR. Prospective studies to further understand the clinical implication of these findings are warranted.