Purpose: Little is known about the relationship between the level of platelet NOD-like receptor protein 3 (NLRP3) and the severity of acute coronary syndrome (ACS) or the prognostic value of platelet NLRP3 for percutaneous coronary intervention (PCI).
Methods: Platelets collected from 25 healthy subjects, 23 patients with stable angina pectoris (SAP), and 72 patients with ACS were analyzed by Western blotting and real-time fluorescence quantitative PCR (qPCR). A total of 152 patients with ACS who had undergone PCI were included in this study to evaluate the prognostic value of platelet NLRP3 .
Results: The levels of platelet NLRP3  in both the healthy and SAP groups were clearly lower than in the ACS group (P < 0.001). According to the Pearson correlation analysis, the expression of platelet NLRP3  was closely related to the mean platelet volume (MPV), left ventricular ejection fraction (LVEF), the Gensini score, and the Global Registry of Acute Coronary Events (GRACE) score (all P < 0.001). Multivariate logistic regression analysis identified NLRP3  as an independent risk factor for adverse cardiovascular events (ACEs) after PCI (P =0.004). The proportion of patients with high NLPR3  expression (the NLRP3 -high group) remaining free of adverse events for 3 years was remarkably lower than that in patients with low NLPR3  expression (the NLRP3 -low group; P =0.024). The NLRP3 -high group had a significantly higher proportion of patients with interleukin-1β–expressing (20.4%± 6.1%) platelets than the NLRP3 -low group (10.7%± 3.5%, P < 0.001). Moreover, the NLRP3 -high group exhibited higher platelet activity, as indicated by increased PAC-1 binding and CD62P expression, compared with the NLRP3 -low group (P < 0.001).
Conclusion: These results indicated that platelet NLRP3  was a novel potential prognostic factor for patients with ACS that underwent PCI.
Keywords: platelet NLRP3, acute coronary syndromes, percutaneous coronary intervention, inflammation, prognosis