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

Abstract

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.

Restoration of von Willebrand factor after transcatheter aortic valve replacement—A possible cause for posttranscatheter aortic valve replacement thrombocytopenia?

“…32,33 Ibrahim et al found that patients receiving a clopidogrel loading dose before TAVR showed a significantly lower DPC. 20 This finding supports the hypothesis of an increased platelet consumption through activation, since clopidogrel inhibits platelet aggregation.…”

“…The percentual change 6 h after TAVR was calculated for platelet count (DPC = 100 × [baseline platelet count – 6 h platelet count]/baseline platelet count) and vWF:Ac/Ag ratio (ΔvWF = 100 × [baseline vWF:Ac/Ag ratio – 6 h vWF:Ac/Ag ratio]/baseline vWF:Ac/Ag ratio). In previous publications, different cut‐off values at 50% (at nadir), 10 30% (at nadir), 13 or 20% (after 1 day) 20 were used. To analyze possible causative factors in the present study early DPC was analyzed, accordingly a lower DPC at 20% was chosen as cut off value.…”

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

“…Notably, even nuisance thrombocytopenia may cost substantial resources by increasing hospital stay [10]. Several general mechanisms to explain post-TAVI thrombocytopenia have been proposed, including drug toxicity (e.g., heparin, aspirin, clopidogrel, warfarin, and novel oral anticoagulants), thromboinflammation, increased platelet consumption, mechanical damage due to shear stress (e.g., in case of paravalvular leak), activation of the coagulation cascade, decreased platelet production, and impaired platelet renewal, as well as dilution pseudothrombocytopenia [4,[11][12][13][14][15]. Further understanding the causes of thrombocytopenia is urgently needed to improve next-generation devices.…”

Between a Rock and a Hard Place: How to Use Antithrombotics in Patients Undergoing Transcatheter Aortic Valve Replacement

“…3 New data suggest that P2Y 12 inhibition prior to the procedure may blunt the severity of TAVR-associated thrombocytopenia. 8 In-hospital and early thromboembolic event rates after TAVR range between 2-4%. 9 More than 70% of these events occur within 2 days of the procedure.…”