Repetitive early stent thrombosis in a patient with the CYP2C19*3/*3 genotype

Area of Science:

• Cardiology
• Pharmacogenomics
• Internal Medicine

Background:

• Dual antiplatelet therapy (DAT) is standard after coronary stent placement.
• Clopidogrel response can vary due to genetic factors, particularly CYP2C19 polymorphisms.
• Stent thrombosis remains a serious complication despite standard therapy.

Observation:

• A patient experienced recurrent stent thrombosis despite standard DAT (aspirin and clopidogrel).
• Platelet function tests revealed inadequate antiplatelet effect from clopidogrel.
• Genetic analysis identified the patient as a poor metabolizer with the CYP2C19*3/*3 genotype.

Findings:

• The patient's CYP2C19*3/*3 genotype prevented adequate conversion of clopidogrel to its active form.
• This led to insufficient platelet inhibition and contributed to repeated stent thrombosis.
• This case demonstrates a direct link between poor clopidogrel metabolism due to genotype and stent thrombosis.

Implications:

• Pharmacogenetic testing for CYP2C19 genotype may be crucial for patients undergoing stenting.
• Personalized antiplatelet therapy strategies are needed for poor metabolizers.
• Understanding genetic factors can help prevent adverse cardiovascular events like stent thrombosis.