Dual antiplatelet therapy (DAPT) remains a cornerstone of treatment following percutaneous coronary intervention (PCI). However, interindividual variability in response to clopidogrel, largely influenced by CYP2C19 genetic polymorphisms, may increase the risk of ischemic events and stent thrombosis. Personalized antiplatelet therapy guided by genetic testing has emerged as a precision medicine strategy.

Objective

To evaluate the clinical effectiveness and safety of genotype-guided antiplatelet therapy compared with conventional treatment in patients undergoing PCI.

Methods

A prospective multicenter observational study was conducted among 620 PCI patients. CYP2C19 genotyping was performed before hospital discharge. Patients were categorized into genotype-guided and conventional treatment groups. Primary outcomes included major adverse cardiovascular events (MACE), stent thrombosis, myocardial infarction, stroke, and bleeding complications at 12 months.

Results

Loss-of-function (LOF) alleles were identified in 34.7% of patients. Patients with LOF alleles receiving ticagrelor or prasugrel experienced significantly lower MACE rates compared with clopidogrel-treated patients (6.8% vs. 14.9%, p=0.01). Definite stent thrombosis occurred in 1.3% versus 4.7% respectively. Major bleeding rates were comparable between groups.

Conclusion

Genotype-guided antiplatelet therapy improves clinical outcomes after PCI by reducing ischemic events and stent thrombosis without significantly increasing major bleeding. Personalized antiplatelet strategies represent an important advancement in precision cardiovascular medicine.