Abstract: Abstract: Objective　To investigate the relationship between proprotein invertase subtilisin 9 (PCSK9) and recent adverse cardiovascular events in elderly patients with chronic heart failure. Methods　A total of 126 elderly patients with chronic heart failure were selected. All patients were followed up for 12 months. According to whether there were adverse cardiovascular events, the patients were divided into the poor prognosis group (n=40) and the good prognosis group (n=86). The relevant data and serum PCSK9 levels were compared between the two groups. The risk factors of poor prognosis in elderly patients with chronic heart failure were analyzed by multivariate Logistic regression equation, and the predictive value of relevant indicators on the risk of recent adverse cardiovascular events was analyzed by subject operating characteristic curve (ROC). The incidence of adverse cardiovascular events in patients with different expression levels of PCSK9 was analyzed. Results　New york heart association (NYHA) grade scale of Ⅳ, PCSK9 and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were significantly higher in the poor prognosis group than those in the good prognosis group, and left ventricular ejection fraction (LVEF) was significantly lower than those in the good prognosis group (P＜0.05). Multivariate Logistic regression analysis showed that NYHA grade with grade Ⅳ (OR=1.540, 95%CI: 1.150-2.063) and high levels of PCSK9 (OR=1.679, 95%CI: 1.132-2.489), NT-proBNP (OR=1.383, 95%CI: 1.005-1.903) were risk factors for poor prognosis in elderly patients with chronic heart failure (P＜0.05). ROC curve analysis showed that the area under the curve of PCSK9 and NT-proBNP for predicting recent adverse cardiovascular events in elderly patients with chronic heart failure was 0.837 (95%CI: 0.755-0.919) and 0.740 (95%CI：0.635-0.845). The incidence of adverse cardiovascular events was 43.75% (28/64) in the PCSK9 high expression group, which was significantly higher than 19.35% (12/62) in the PCSK9 low expression group, and the difference was statistically significant (χ2=8.650，P＜0.01). Conclusion　The expression level of PCSK9 is closely related to the risk of recent adverse cardiovascular events in elderly patients with chronic heart failure, and it has high predictive value for the risk of recent adverse cardiovascular events.

Key words: heart failure, proprotein convertase 9, aged, prognosis, adverse cardiovascular events, predictive value