title: Comparison of Multiplate and VerifyNow platelet function tests in predicting clinical outcome in patients with acute coronary syndromes.
abstract: BACKGROUND
  This study examined the ability of two widely used "point of care" platelet function assays, VerifyNow and Multiplate, to predict adverse outcomes in patients with acute coronary syndromes (ACS).
  
  
  METHODS
  We examined platelet reactivity using VerifyNow and Multiplate P2Y12assays in patients with ACS and the relationship between platelet reactivity and both MACE (defined as a composite of death, myocardial infarction, stroke, stent thrombosis and unplanned revascularisation) and TIMI major bleeding at 1year.
  
  
  RESULTS
  In 619 ACS patients, 65 patients (10.5%) had experienced MACE at 1year and 6 patients (1%) had TIMI major bleeding events. The two measures of platelet reactivity were only moderately correlated (Rho=0.43, p=0.0001). Both measures demonstrated a statistically significant relationship with MACE, with area under the curve for VerifyNow of 0.632 (0.001) and for Multiplate of 0.577 (p=0.04), and neither measure showed a significant relationship with bleeding. Logistic regression analysis found that only VerifyNow was a statistical predictor of MACE (p=0.01). MACE occurred in 16% of those classified as having HPR using VerifyNow compared to 7% in those without HPR (odds ratio of 2.6 (95% CI 1.5-4.4, p=0.001). In those classified as having HPR by the Multiplate assay, MACE occurred in 13% compared to 9% of those without HPR (Odds ratio 1.5 95% CI 0.9-2.5, p=0.11).
  
  
  CONCLUSIONS
  The two points of care platelet function tests examined in this study were only moderately correlated. The VerifyNow assay demonstrated a stronger relationship to MACE than the Multiplate assay.
authors.affiliation: University of Otago, Wellington, New Zealand; Wellington Cardiovascular Research Group, New Zealand. Electronic address: peter.larsen@otago.ac.nz.
authors.forename: Peter D
authors.initials: PD
authors.lastname: Larsen
authors.affiliation: University of Otago, Wellington, New Zealand; Wellington Cardiovascular Research Group, New Zealand.
authors.forename: Ana S
authors.initials: AS
authors.lastname: Holley
authors.affiliation: Wellington Cardiovascular Research Group, New Zealand; Department of Cardiology, Wellington Hospital, New Zealand.
authors.forename: Alexander
authors.initials: A
authors.lastname: Sasse
authors.affiliation: Department of Cardiology, Wellington Hospital, New Zealand.
authors.forename: Ali
authors.initials: A
authors.lastname: Al-Sinan
authors.affiliation: Wellington Cardiovascular Research Group, New Zealand; Department of Cardiology, Wellington Hospital, New Zealand.
authors.forename: Sarah
authors.initials: S
authors.lastname: Fairley
authors.affiliation: Wellington Cardiovascular Research Group, New Zealand; Department of Cardiology, Wellington Hospital, New Zealand.
authors.forename: Scott A
authors.initials: SA
authors.lastname: Harding
mesh_terms: D054058:Acute Coronary Syndrome / Q000175:diagnosis* / Q000188:drug therapy*; D000368:Aged; D001792:Blood Platelets / Q000187:drug effects; D005260:Female; D006470:Hemorrhage / Q000139:chemically induced; D006801:Humans; D008297:Male; D008875:Middle Aged; D010975:Platelet Aggregation Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D010979:Platelet Function Tests / Q000379:methods*; D019095:Point-of-Care Systems; D011379:Prognosis
chemical_list: D010975:Platelet Aggregation Inhibitors
keywords: Acute myocardial infarction; Antiplatelet agents; Aspirin; Clopidogrel; Point-of-care testing