Clopidogrel Platelet Function Tests
Caveats and Controversies
This slide summarizes a little over 2 years of VerifyNow testing in Mayo Clinic Florida, looking at selected patients suspected of being resistant to clopidogrel or who received a loading dose of clopidogrel in preparation for surgery, often for stent placement with the goal of prevention of stent thrombosis. If 20% or less inhibition is used as the cutoff for clopidogrel resistance, 37% of the patients tested were found to be resistant out of over 750 patients tested. If however 30% was used as the cutoff for resistance, slightly over 50% of patients were resistant.
Results of VerifyNow Testing
Jump to section:
- 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