Objective:This study aimed to investigate the predictive value of N-terminal pro-B-type natriuretic peptide (NT-proBNP) trajectory on future major adverse cardiovascular events (MACE) in patients with stable coronary artery disease (SCAD) after percutaneous coronary intervention (PCI).Methods:A retrospective cohort study was conducted on SCAD patients admitted to the Department of Cardiology at Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, from January 2013 to December 2021. A total of 828 subjects were enrolled, comprising 592 males and 236 females, with an average age of (66.44±11.71) years. SCAD patients post-percutaneous coronary intervention (PCI) were stratified into three NT-proBNP trajectory groups: T1 Low-Low (219 cases), T2 Medium-Low (363 cases), and T3 High-High (246 cases). The median follow-up time was 2.1 years, and the maximum follow-up time was 9 years. The primary clinical endpoint event was MACE. The NT-proBNP concentration in patients′ serum was measured using enzyme-linked fluorescent assay, and different trajectory groups were determined using latent class trajectory modeling. The association between NT-proBNP trajectory and occurrence of MACE in SCAD patients was evaluated using Kaplan-Meier survival curves and multivariable Cox proportional hazards regression models.Results:A total of 67 (8.1%) major adverse cardiovascular events occurred, including 43 cases (5.2%) of all-cause mortality, 13 cases (1.6%) of heart failure death, 9 cases (1.1%) of non-fatal myocardial infarction, and 15 cases (1.8%) of non-fatal stroke. Kaplan-Meier survival curve analysis showed significant differences in survival rates among T1, T2, and T3 groups of SCAD patients for MACE, all-cause mortality, and heart failure death (all P<0.001). In the multivariable Cox regression analysis, the risk of MACE occurrence for patients in the T2 group and T3 group was 1.708 times (95% CI 0.72-4.05) and 3.842 times (95% CI 1.625-9.081) compared to the T1 group, respectively. Moreover, a statistically significant linear trend was observed for the risk of MACE occurrence across trajectory groups ( P<0.001). Conclusions:NT-proBNP trajectory groups after PCI in SCAD patients are strongly associated with the risk of MACE occurrence and can serve as an independent predictor for MACE. Dynamic monitoring of NT-proBNP during follow-up to obtain longitudinal trajectories helps identify high-risk SCAD patients and implement timely effective intervention measures.