The net clinical benefit of personalized antiplatelet therapy in patients undergoing percutaneous coronary intervention.

This was a prospective study comparing two groups: personalized and non-personalized treatment with P2Y12 receptor blockers during a 12-month follow-up. We aimed to investigate whether personalized antiplatelet treatment in patients with high on-treatment platelet reactivity (HTPR) improves clinical outcome. Platelet reactivity was assessed by adenosine diphosphate induced aggregation using a multiple electrode aggregometry (MEA) in 798 patients with coronary artery disease undergoing percutaneous coronary intervention (PCI). Patients with HTPR received up to four repeated loading doses of clopidogrel or prasugrel in the personalized treatment group (n=403), whereas no change in the treatment strategy was undertaken in patients with HTPR in the non-personalized treatment group (n=395). There were fewer major adverse cardiac events (MACE) in the personalized treatment group than in the non-personalized treatment group (7.4% compared with 15.3% respectively; P<0.001). The multivariate Cox regression analysis showed that the relative risk to develop MACE was 51% lower in the personalized treatment group as compared with the non-personalized treatment group [hazard ratio (HR)=0.49; 95% confidence interval (CI): 0.31-0.77; P<0.001]. Similarly, there was a clear net benefit of the personalized antiplatelet treatment over the non-personalized treatment (ischemic and bleedings events: 8.2% versus 18.7% respectively; HR=0.46; 95%CI: 0.29-0.70; P<0.001). Further analysis indicated that patients with aggregation values within the therapeutic window (21-49 units) experienced the lowest event rates (stent thrombosis and major bleeding: 2.5%) as compared with poor responders (≥50 units: 5.4%) or ultra-responders (0-20 units: 5.2%). In conclusion, personalized antiplatelet treatment might improve patients' outcome without increasing bleeding complications compared with the non-personalized treatment during a 12-month follow-up.