Background Soluble suppression of tumorigenicity 2 (ST2) is closely related to the development of cardiovascular disease, but the level of acute coronary syndrome (ACS) and the relationship between ST2 and ACS are unclear. Patients and Methods Patients with the acute coronary syndrome were divided into the unstable angina pectoris (USAP) group (n = 65) and non‐ST‐segment elevation myocardial infarction (NSTEMI) group (n = 58), and the healthy population, without chest pain and with normal coronary CT, was included as a control group (n = 55). Laboratory index levels were collected from each participant. The baseline information was reviewed and analyzed. The binary logistic regression was used to explore the relation of ST2 levels with the occurrence of ACS and NSTEMI, and the diagnostic performance of ST2 for diagnosing ACS or NSTEMI was evaluated using a receiver‐operating characteristic (ROC) curve. Results The level of ST2 was found significantly higher in NSTEMI than in USAP and was higher in USAP than in control (p < 0.01). ST2 levels were positively correlated with ALT, AST, and BNP in the control group, were negatively correlated with HGB and TG in the USAP group, and were positively correlated with WBC, GLU, BNP, and Gensini scores in the NSTEMI group. Multivariate analysis revealed that the occurrence of ACS was associated with ST2, BNP, GLU, TC, BUN, WBC, and PLT, and the occurrence of NSTEMI was associated with AST, WBC, LDL‐C, and ST2. Meanwhile, ST2 levels achieved good performance for ACS and NSTEMI diagnostician. Conclusion ST2 could be used as an auxiliary diagnostic indicator for the occurrence of ACS and NSTEMI.

Objective. LCZ696 (sacubitril/valsartan) is an angiotensin II (Ang II) type 1 receptor-neprilysin inhibitor, with effects of immunosuppression, anti-inflammation, antiapoptosis, and antioxidation. The present study was aimed at determining whether LCZ696 has a protective effect against isoproterenol-induced acute heart failure (AHF) in rats. Methods. SD rats were randomly divided into four groups: control group, HF group, LCZ696 group, and enalapril group. The cardiac function of rats was evaluated using echocardiographic parameters, heart weight (HW), serum levels of cardiac troponin I (cTnI), and lactate dehydrogenase (LDH). HE is staining, which was used to determine the pathological damage of rat myocardial tissue. Also, we measured oxidative stress markers including reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT). Finally, the expression of Nrf2 signaling pathway-related proteins was determined using Western blot. Results. Compared with the HF group, LCZ696 could significantly improve cardiac function and myocardial injury in rats and reduce AHF-induced oxidative stress. In addition, the results of Western blot confirmed that LCZ696 could upregulate the expression of Nrf2 and HO-1 while decreasing Keap1 expression. Conclusion. LCZ696 ameliorates isoproterenol-induced AHF in rats by alleviating oxidative stress injury and activating the Nrf2 signaling pathway.