Which Platelet Function Test Best Reflects the In Vivo Plasma Concentrations of Ticagrelor and Its Active Metabolite?
Condition: Infarction; Myocardial Infarction; Cardiovascular Diseases; Heart Diseases; Ischemia; Myocardial Ischemia; Necrosis; Pathologic Processes; Vascular Diseases
MeSH terms: Cardiovascular Diseases; Heart Diseases; Myocardial Infarction; Vascular Diseases; Myocardial Ischemia; Infarction; Ischemia; Necrosis; Pathologic Processes
Study type: Observational

Summary: 
      Ticagrelor is a direct-acting, reversible platelet P2Y12 receptor inhibitor recommended by
      the recent European Society of Cardiology guidelines in patients with acute coronary
      syndromes (ACS) (class of recommendation I, level of evidence B). Ticagrelor inhibits
      platelet function stronger, faster and more consistently than clopidogrel, the former
      standard of antiplatelet therapy. In the landmark PLATO trial (Study of PLATelet inhibition
      and patient Outcomes), ticagrelor therapy as compared with clopidogrel treatment was
      associated with the reduced occurrence of major adverse cardiovascular events and all-cause
      mortality, but also resulted in a small, but statistically significant, increase in the rate
      of major bleeding. The optimum choice of antiplatelet treatment, aimed to provide each
      patient with maximum protection against ischemic events, while minimizing the risk of
      bleeding complications, is the challenge of contemporary ACS therapy. The tool which may help
      physicians and facilitate clinical decision making is platelet function testing. According to
      the guidance of both European and American groups of experts, there are three currently
      recommended platelet function tests, namely the VerifyNow device, the Multiplate analyzer and
      the Vasodilator Stimulated Phosphoprotein Phosphorylation (VASP) assay. It needs to be
      emphasized that none of these three methods is preferred over others. So far there are no
      studies linking pharmacokinetic analysis of ticagrelor and its active metabolite with
      comparative evaluation of platelet reactivity. The aim of this trial is to assess the
      relationship between concentrations of ticagrelor and its active metabolite (AR-C124910XX)
      and results of all three recommended platelet function tests in patients with myocardial
      infarction. Patients who receive GP IIb/IIIa receptor inhibitor will be excluded from the
      primary analysis.

      Statistical analysis: The correlation will be assessed using correlation coefficients and
      intraclass correlation coefficients. while the agreement between the results of the compared
      platelet function tests will be measured using the Kappa statistic and Bland-Altman analysis.
    


Observational model: Cohort
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Patients with myocardial infarction
      
Keywords: ticagrelor; ticagrelor active metabolite (AR-C124910XX); platelet function tests; the flow cytometric VASP assay; the VerifyNow® device; the Multiplate® analyzer; pharmacokinetics; pharmacodynamics; Multiplate® ADPtest; VerifyNow® PRUTest™; Platelet VASP/P2Y12 assay