Long-Term Impact of Platelet Reactivity and Clinical Risk on Clinical Outcomes in Patients With Coronary Artery Disease: Analysis of the PTRG-DES Registry

Abstract

BACKGROUND: Platelet reactivity (PR) and clinical risk factors are known to have impact on outcomes in patients receiving percutaneous coronary intervention (PCI). We aimed to assess the interaction of PR and clinical risk assessment using the Thrombolysis in Myocardial Infarction Risk Score for Secondary Prevention (TRS2P) on adverse clinical outcomes following PCI. METHODS: From the PTRG-DES (Platelet function and Genotype-Related Long-Term Prognosis in Drug-Eluting Stent-Treated Patients With Coronary Artery Disease) registry, 11 714 patients who underwent PCI and had a mean platelet reactivity unit (PRU) value were studied. Clinical risk was stratified using the TRS2P as low clinical risk (score 0-1) or high clinical risk (>= 2), and PR was stratified as high PR (HPR, PRU >= 252) and non-HPR (PRU <252). The primary outcome was a composite of cardiac death, myocardial infarction, and stent thrombosis. Landmark analysis was performed at 1- and 12 months after PCI. RESULTS: Among total population, mean PRU was 217.8 +/- 78.7, and mean TRS2P was 1.56 +/- 1.12. Over the long-term follow-up period, the primary outcome occurred in 335 (5.3%) patients. Patients with both high clinical risk and HPR had the highest incidence of the primary outcome (9.4%), followed by high clinical risk/non-HPR (5.9%), low clinical risk/HPR (4.8%), and low clinical risk/non-HPR (3.9%) (P<0.001). Compared with low clinical risk/non-HPR patients, those with both high clinical risk and HPR had a 3.25-fold higher risk of the primary outcome (hazard ratio, 3.25 [95% CI, 2.38-4.42]; P<0.001). Both PRU and TRS2P were independent predictors of the primary outcome. In landmark analyses, the risk of primary outcome within 1 month after PCI were mainly determined by PRU, while outcome beyond 1 month after PCI was mainly determined by TRS2P. CONCLUSIONS: In the secondary prevention after percutaneous coronary intervention, platelet reactivity and clinical risk had additive value in predicting outcomes. Platelet reactivity had greater relative impact within 1 month while clinical risk had greater relative impact beyond 1 month.