【Abstract】Objective To explore the application value of four-dimensional automatic right ventricular quantitative analysis (4D Auto RVQ) technology in assessing right ventricular function in patients with chronic heart failure (CHF) of varying severity. Methods 99 in-patients with CHF were prospectively selected from April 2023 to January 2024. Based on the six-minute walk distance (6MWD), the patients were divided into three groups: mild heart failure group (6MWD> 450m) with 33 cases, moderate heart failure group (150m≤ 6MWD≤ 450m) with 33 cases, and severe heart failure group (6MWD< 150m) with 33 cases. All patients underwent routine echocardiography, and 4D Auto RVQ technology was applied to obtain four-dimensional right ventricular ejection fraction (4D-RVEF), four-dimensional right ventricular end-diastolic volume index (4D-RVEDVI), four-dimensional right ventricular end-systolic volume index (4D-RVESVI), four-dimensional right ventricular stroke volume index (4D-RVSVI), four-dimensional tricuspid annular plane systolic excursion (4D-TAPSE), four-dimensional right ventricular fractional area change (4D-RVFAC). Moreover, one-way ANOVA, Kruskal-Wallis H-test, Spearman''s correlation analysis, and ordinal logistic regression were performed for statistical analyses. Results 4D-RVEF, 4D-RVSVI, 4D-TAPSE, 4D-RVFAC, and the absolute values of right ventricular global longitudinal strain (RVGLS) and right ventricular free wall longitudinal strain (RVFWLS) of mild heart failure group, moderate heart failure group and severe heart failure group decreased sequentially (all P < 0.05). Correlation analysis showed that 4D-RVEF, 4D-RVSVI, 4D-TAPSE, 4D-RVFAC, and the absolute values of RVGLS and RVFWLS were positively correlated with 6MWD (r=0.904, 0.567, 0.646, 0.644, 0.634, 0.653, all P < 0.05). Ordinal logistic regression analysis showed that 4D-RVEF had a significant negative impact on the severity of heart failure in patients (regression coefficient: -1.520, 95% CI: 0.092~0.522, P < 0.05). Conclusion 4D Auto RVQ technology can quantitatively evaluate right ventricular function in patients with CHF of varying severity, and 4D-RVEF has a significant correlation with the severity of heart failure in patients.