Tehran University of Medical Sciences Archives of Anesthesiology and Critical Care 2423-5849 12 3 2026 01 01 273 280 Ahmed Abdelmoniem Critical Care Medicine Department, Faculty of Medicine, Kaser Elani, Cairo University, Cairo, Egypt. Mennatullah Abdel-Maksoud Critical Care and Intensive Care Medicine Department, Faculty of Medicine, Misr University for Science and Technology (MUST), 6th of October, Egypt. Amr Elhadidi Critical Care Medicine Department, Faculty of Medicine, Kaser Elani, Cairo University, Cairo, Egypt. Ahmed Battah Critical Care Medicine Department, Faculty of Medicine, Kaser Elani, Cairo University, Cairo, Egypt. Doaa Moubarez Critical Care Medicine Department, Faculty of Medicine, Kaser Elani, Cairo University, Cairo, Egypt. 2025 07 28 2025 08 11 Background: Accurate assessment of volume status in cases with acutely decompensated heart failure (ADHF) is crucial for prognostication and management. While brain natriuretic peptide (pro-BNP) and echocardiographic inferior vena cava (IVC) diameter are commonly used surrogate markers, their combined prognostic value has not been thoroughly established. Methods: This prospective cohort study included 100 adults with ADHF and reduced ejection fraction (EF <40%). Pro-BNP levels and IVC diameter were assessed on admission and after 72 hours. The primary outcome was in-hospital mortality; secondary outcomes included complications and 30-day cardiovascular mortality. Repeated measures ANOVA, ROC analysis, and correlation testing were performed to evaluate predictive value. Results: In-hospital mortality occurred in 21% of cases. Pro-BNP levels were significantly higher in non-survivors both on admission (median: 11,542 pg/mL vs. 6,350 pg/mL, p<0.001) and after 72 hours (3,695 pg/mL vs. 3,029 pg/mL, p<0.001). Similarly, IVC diameter was significantly greater in the mortality group at both time points (2.85 cm vs. 2.2 cm on admission, p<0.001; 2.15 cm vs. 1.9 cm after 72 hours, p=0.004). ROC analysis revealed strong predictive power for in-hospital mortality with admission Pro-BNP >8,856 pg/mL (AUC=0.89) and IVC diameter >2.55 cm (AUC=0.81). A combined model incorporating both parameters at admission yielded the highest diagnostic accuracy (AUC=0.89; NPV=95.4%). Conclusion: Pro-BNP and IVC diameter are independent yet complementary predictors of in-hospital mortality in ADHF. Combined early assessment significantly enhances risk stratification and may guide intensive monitoring and therapeutic strategies. https://aacc.tums.ac.ir/index.php/aacc/article/view/1359