Objective To investigate the relationship between estimated pulse wave velocity (ePWV) and 1-year mortality in critically ill patients with acute myocardial infarction (AMI). Methods Adult AMI patients from the Medical Information Mart for Intensive Care IV (MIMIC-IV, v2.2) Database were selected. Patients were categorized into the survival and the non-survival groups based on 1-year outcomes. To minimize bias, propensity score matching (PSM) was used. Cumulative survival in each group was assessed using Kaplan-Meier curves. Restricted cubic spline (RCS) analysis and Cox regression were used to explore the relationship between ePWV and 1-year mortality. The robustness of the results was further verified by subgroup analysis. Results A total of 4 242 adult AMI patients were included in the final analysis. ePWV was linearly associated with the risk of death at one year of discharge as shown by the RCS (nonlinear P=0.407, P0.001). 1 552 pairs of patients were matched after PSM. The mortality rate was significantly higher in the high ePWV group compared with the low ePWV group (P0.001). Kaplan-Meier curves showed that before and after PSM, the 1-year cumulative survival rate at discharge for AMI patients in the high ePWV group was significantly lower than that in the low ePWV group (χ²=191.64, P0.001; χ²=108.76, P0.001). After adjusting for various confounders, multivariate Cox regression analysis showed that elevated ePWV was an independent factor for all-cause mortality in patients with AMI [hazard ratio (HR) 2.48, 95% confidence interval (CI) 2.09~2.95, P0.001]. Gender and acute kidney injury were shown to be significantly interactive with ePWV in subgroup analysis (P=0.01; P=0.035). Conclusion High ePWV was significantly associated with an increased risk of death at 1 year of hospital discharge in AMI patients. ePWV is an independent predictor of 1-year mortality in critically ill patients with AMI.