Predictive Value of Platelet FcγRIIa in Patients Treated With PCI Compared With Medical Therapy Alone After Myocardial Infarction

BACKGROUND: In patients with myocardial infarction (MI), quantifying platelet FcɣRIIa (pFCG) stratifies the risk of subsequent MI, stroke, and death. This report is a subgroup analysis of outcomes in patients treated with percutaneous coronary intervention (PCI) or medical management alone in an 800-patient, 25-center trial. METHODS: Patients were enrolled in a prospective, noninterventional trial during hospitalization for type 1 MI (ST-segment–elevation and non–ST-segment–elevation). Inclusion criteria included at least 2 of the following: aged ≥65 years, multivessel coronary artery disease, prior MI, chronic kidney disease, or diabetes. Flow cytometry was used to quantify pFCG at a core laboratory. High and low pFCG were defined by a prespecified threshold. The primary end point was the composite of MI, stroke, and death. RESULTS: Patients treated with medical therapy alone (n=151) had a greater occurrence of the primary end point (23.8%) than those treated with PCI (n=490, 8.8%). The pFCG test discriminated to a similar extent the risk of the primary end point in both the medical treatment group (hazard ratio, 2.29 [95% CI, 1.18–4.41]; P =0.014) and the PCI group (hazard ratio, 2.57 [95% CI, 1.41–4.69]; P =0.002). There was no significant association between pFCG and clinically relevant bleeding in the medical treatment group (hazard ratio, 1.22 [95% CI, 0.29–5.10]) or the PCI group (hazard ratio, 1.56 [95% CI, 0.67–3.61]). CONCLUSIONS: Quantifying pFCG discerned the risk of subsequent cardiovascular events among patients treated with medical therapy alone or PCI. This prognostic information will be useful for clinical decisions that balance ischemic and bleeding risk. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT05175261.