Platelet function testing guided antiplatelet therapy reduces cardiovascular events in Chinese patients with ST-segment elevation myocardial infarction undergoing percutaneous coronary intervention: The PATROL study.

BACKGROUND: Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 receptor inhibitor has become the standard of care to reduce thrombotic events in patients with acute coronary syndrome or after percutaneous coronary intervention (PCI). The role of routine platelet function testing (PFT) in patients treated with DAPT after PCI remains controversial and evidence of PFT-guided antiplatelet therapy for patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary PCI is limited. METHODS: We analyzed 1,353 consecutive STEMI patients undergoing primary PCI. PFT was performed 72 hr postprocedure using a vasodilator-stimulated phosphoprotein assay. The primary endpoint of major adverse cardio-cerebral events (MACCEs) was defined as a composite of all-cause death, cardiac death, nonfatal myocardial infarction, target vessel revascularization, and ischemic stroke. Patients with high platelet reactivity (HPR) were randomized to receive an intensified antiplatelet strategy by switching from clopidogrel to ticagrelor (HPR switch group) or to continue on clopidogrel (HPR nonswitch group). One-year clinical outcomes were compared among the groups. RESULTS: The baseline clinical characteristics were comparable across all groups (all p > .05). At the 1-year clinical follow-up, the primary endpoint of MACCE was significantly higher in the HPR nonswitch group than in the non-HPR and HPR switch groups (19.49% vs. 10.20% or 8.57%, p < .05), which was mainly caused by higher mortality (14.87% vs. 4.51% or 5.71%, p < .05). Major bleeding events were comparable across the groups. CONCLUSIONS: In STEMI patients with HPR, identified by vasodilator stimulated phosphoprotein (VASP)-determined PFT, switching clopidogrel to ticagrelor could significantly improve 1-year clinical outcomes without increasing the risk of bleeding.