Clopidogrel Platelet Function Tests
Caveats and Controversies
The normal genotype for the CYP2C19 gene is designated as CYP2C19*1. Patients who possess two copies of this have normal metabolism of clopidogrel, which is referred to as extensive metabolism. Most of the polymorphisms of the CYP2C19 gene result in less activity of the enzyme and patients with one copy of the normal genotype and one of the polymorphisms have decreased metabolism of clopidogrel which is called intermediate metabolism. Patients with two copies of the same polymorphism or one copy each of two different polymorphisms may have markedly decreased activity and are known as poor metabolizers. CYP2C19*2 is the most common of the polymorphisms and both CYP2C19*2 and CYP2C19*3 result in no or very little activity of the enzyme produced by that gene.
Number of Gene Polymorphisms
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- Learning Objectives
- Platelet Function Tests for the Detection of Clopidogrel Resistance1
- Platelet Function Tests for the Detection of Clopidogrel Resistance
- Caveat: There Is No Perfect Platelet Function Test...
- Problems With Testing For Clopidogrel
- How We Choose a Testing Method
- Methodology Table
- Platelet Function Testing Available at Mayo Clinic Florida
- Light Transmission Platelet Aggregometry Studies (LTA)
- Platelet Aggregation (Cont'd)
- Normal Patient
- Accumetrics VerifyNow Test
- VerifyNow P2Y12 Test
- P2Y12 Test Interferences
- P2Y12 Antagonists2
- Can These Platelet Function Tests Be Used for Ticagrelor (Brilinta/Brilique)?
- PFA–100 (Cont'd)
- INNOVANCE PFA P2Y
- TEG — Platelet Mapping
- Results of VerifyNow Testing
- 2009–2011 Clopidogrel Response at 30%
- Genetic Testing: Clopidogrel Metabolism
- Clopidogrel Metabolism
- Number of Gene Polymorphisms
- Clopidogrel Metabolism and Genetic Polymorphisms
- Why Do Genetic Testing?
- Clopidogrel Genetics (Cont'd)
- Caveats — Other Reasons for Poor Response to Clopidogrel
- CYP2C19 Polymorphism May Require Another Factor
- Controversy for Clopidogrel
- Warning: Diminished Effectiveness In Poor Metabolizers
- What Does Warning Mean For Clinicians With Patients On Clopidogrel?
- FDA Answer
- More Questions