Clinical InvestigationInterventional CardiologyDoes baseline hematocrit influence the assays of on-treatment platelet reactivity to clopidogrel?
Section snippets
Study population and data collection
The study cohort included patients ≥18 years of age presenting for elective and urgent PCI who were consecutively enrolled in a prospective observational registry from October 2009 to March 2012. Patients who received the glycoprotein IIb/IIIa inhibitor eptifibatide up to 24 hours before platelet reactivity testing were excluded (no patients received abciximab or tirofiban). Similarly, patients on warfarin, nonsteroidal anti-inflammatory drugs, or with a contraindication for aspirin or
Results
Platelet reactivity was tested in 466 consecutive patients with VN and LTA ADP 5 and 20 μM. Baseline characteristics stratified by hematocrit ≥39% are presented in Table I. To evaluate the influence of hematocrit upon platelet function assays, further analysis was done by dividing the patients into quartiles (Q1: 25-35.9, Q2: 36-38.9, Q3: 39-41.9, Q4: 42-51) based upon baseline hematocrit (percentages). The patients in Q1 and Q2 were considered anemic, and Q3 and Q4 were considered nonanemic.
Discussion
The main findings of the present study are (1) there was clear influence of the hematocrit on PRU and BASE results by VN assay, whereas no such influence was seen with LTA assay; (2) lower hematocrit was independently correlated with HTPR by the VN assay but not by LTA; and (3) the interaction between the hematocrit and the platelet function assay results was shown to impact the predictive power of long-term adverse outcomes for the VN assay but not for the LTA assay.
Currently, several
Conclusions
In the present study, baseline hematocrit is noted to have differential influence on the results of ex vivo platelet functional assays. The PRU measured by the VN P2Y12 assay is clearly influenced by a patient's baseline hematocrit, whereas the platelet reactivity measured by LTA does not seem to be influenced by hematocrit.
References (22)
- et al.
2007 focused update of the ACC/AHA/SCAI 2005 guideline update for percutaneous coronary intervention: a report of the American College of Cardiology/American Heart Association Task Force on Practice guidelines
J Am Coll Cardiol
(2008) - et al.
Assessment of P2Y(12) inhibition with the point-of-care device VerifyNow P2Y12 in patients treated with prasugrel or clopidogrel coadministered with aspirin
Am Heart J
(2009) - et al.
Onset and offset of platelet inhibition after high-dose clopidogrel loading and standard daily therapy measured by a point-of-care assay in healthy volunteers
Am J Cardiol
(2006) - et al.
Variability in individual responsiveness to clopidogrel: clinical implications, management, and future perspectives
J Am Coll Cardiol
(2007) - et al.
Variability in platelet responsiveness to clopidogrel among 544 individuals
J Am Coll Cardiol
(2005) - et al.
Hematocrit alters VerifyNow P2Y12 assay results independently of intrinsic platelet reactivity and clopidogrel responsiveness
J Thromb Haemost
(2013) - et al.
Impact of anemia on platelet response to clopidogrel in patients undergoing percutaneous coronary stenting
Am J Cardiol
(2012) - et al.
Currently available methods for platelet function analysis: advantages and disadvantages
Cardiovasc Revasc Med
(2011) - et al.
Consensus and future directions on the definition of high on-treatment platelet reactivity to adenosine diphosphate
J Am Coll Cardiol
(2010) - et al.
Clopidogrel effect on platelet reactivity in patients with stent thrombosis: results of the CREST Study
J Am Coll Cardiol
(2005)
Platelet function assessment to predict outcomes after coronary interventions: hype or hope?
J Am Coll Cardiol
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<sup>1</sup>H NMR based pharmacometabolomics analysis of urine identifies metabolic phenotype of clopidogrel high on treatment platelets reactivity in coronary artery disease patients
2017, Journal of Pharmaceutical and Biomedical AnalysisCitation Excerpt :The negative correlations between Hct and Hb, and both PRU and BASE but not with the %Inh which were indicated in our study are in line with previous results [36,37]. However, similar correlations were absent in LTA ADP 5 μM and the multiple electrode platelet aggregometry (MEA) ADP when compared to VN-P2Y12 [36,37]. Although VN-P2Y12 and LTA have similar PFT mechanism, VN-P2Y12 uses whole blood specimen rather than platelets rich plasma (PRP); the specimen of LTA.
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