Predictors of Myocardial Sodium Accumulation in Chronic Heart Failure

Objective To identify clinical, laboratory, and imaging predictors of myocardial sodium accumulation in patients with chronic heart failure (CHF). Methods This was a prospective two-center observational study including 15 patients with decompensated CHF on a high-salt diet and 5 healthy volunteers on a low-salt diet. All participants underwent dual-energy computed tomography (DECT) with generation of material decomposition maps (H₂O|Na, H₂O|NaCl) for quantitative assessment of myocardial sodium and NaCl. Estimated plasma osmolarity (eOSM) was calculated as 2[Na⁺] + 2[K⁺] + [Urea] + [Glucose], followed by calculation of osmolyte fractions (PropNa/eOSM, PropUrea/eOSM, etc.). Between-group comparisons, correlation analysis, ROC analysis, and regression modeling (univariate and multivariate models with FDR correction; internal bootstrap validation of the multivariate model) were performed. Results Compared with healthy controls, CHF patients had higher myocardial relative density (HU: 51.69 ± 5.67 vs. 38.65 ± 4.72; p = 0.004) and sodium concentration (72.24 ± 26.38 vs. 25.49 ± 44.04 mmol/kg; p = 0.025). Myocardial sodium concentration correlated inversely with the sodium fraction of eOSM (R=–0.63; p = 0.0027) and positively with the urea fraction (R = 0.66; p = 0.0014). Similar associations were observed for NaCl (R=–0.54; p = 0.015 and R = 0.66; p = 0.0015, respectively). In ROC analysis, sodium and urea fractions of eOSM demonstrated comparable discrimination for low myocardial sodium (AUC = 0.829 and 0.843; Youden thresholds 45.6% and 2.25%, respectively). In a multivariate linear model, myocardial sodium accumulation was associated with reduced sodium (β=–54; p < 0.001) and glucose fractions of eOSM (β=–27; p = 0.014), as well as increased absolute monocyte count (β = 21; p = 0.047). Internal validation confirmed acceptable calibration of the model. Conclusion Patients with decompensated CHF demonstrate increased myocardial sodium content and higher HU on DECT. The plasma osmometric profile—particularly sodium and urea fractions of eOSM—together with inflammatory markers, are associated with myocardial sodium accumulation and may serve as predictors for risk stratification and personalized therapy.