title: Platelet volume indices are associated with high residual platelet reactivity after antiplatelet therapy in patients undergoing percutaneous coronary intervention.
abstract: OBJECTIVE
  It is well known that platelet volume indices are associated with adverse outcomes following percutaneous coronary intervention(PCI). In this study, we investigated the hypothesis whether the association between platelet size and clinical outcomes is the result of high residual platelet reactivity after antiplatelet therapy in patients with large platelets.
  
  
  METHODS
  Between February 2010 and December 2011, a total of 462 consecutive patients with coronary artery disease who were scheduled to undergo planned PCI were enrolled in this study. The degree of platelet aggregation induced by arachidonic acid(AA) and adenosine diphosphate(ADP) was assessed using the Multiple Electrode Platelet Aggregometry(Multiplate(®), Dynabyte, Munich, Germany)(MEA) test. We simultaneously measured the mean platelet volume(MPV) in the same period(Sysmex XE-2100, Mundelein, IL).
  
  
  RESULTS
  The study population consisted of 462 consecutive patients, including 371 stable angina patients and 91 acute coronary syndrome patients. The patients with large platelets(upper quintile of MPV ≥10.6 fL) had significantly high residual platelet reactivity after both aspirin(MEA ASP 9 [5-14] Units vs. 13 [8-18.5] Units, p < 0.001) and clopidogrel(MEA ADP 21 [15-30] Units vs. 24 [18.5-40] Units, p=0.003) treatment. According to a multivariate analysis, having large platelets was independently associated with high residual platelet reactivity after both aspirin (OR 2.52, 95% CI 1.50-4.24, p < 0.001) and clopidogrel(OR 2.86, 95% CI 1.59-5.15, p < 0.001) treatment. Platelet volume indices were not associated with any differences in the incidence of major adverse cardiac events during follow-up.
  
  
  CONCLUSIONS
  Platelets with a higher volume are associated with high residual platelet reactivity after conventional dual antiplatelet therapy.
authors.affiliation: The Cardiovascular Center, Seoul National University Bundang Hospital.
authors.forename: Yun Gi
authors.initials: YG
authors.lastname: Kim
authors.forename: Jung-Won
authors.initials: JW
authors.lastname: Suh
authors.forename: Chang-Hwan
authors.initials: CH
authors.lastname: Yoon
authors.forename: Il-Young
authors.initials: IY
authors.lastname: Oh
authors.forename: Young-Seok
authors.initials: YS
authors.lastname: Cho
authors.forename: Tae-Jin
authors.initials: TJ
authors.lastname: Youn
authors.forename: In-Ho
authors.initials: IH
authors.lastname: Chae
authors.forename: Dong-Ju
authors.initials: DJ
authors.lastname: Choi
mesh_terms: D000368:Aged; D001792:Blood Platelets / Q000502:physiology*; D003324:Coronary Artery Disease / Q000097:blood / Q000628:therapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D063847:Mean Platelet Volume; D008875:Middle Aged; D062645:Percutaneous Coronary Intervention; D010974:Platelet Aggregation; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D011379:Prognosis; D012189:Retrospective Studies
chemical_list: D010975:Platelet Aggregation Inhibitors