A normal sodium diet preserves serum sodium levels during treatment of acute decompensated heart failure: A prospective, blind and randomized trial

Background: We tested the hypothesis that a normal sodium diet could be associated with preservation of serum sodium during treatment of acute decompensated heart failure (ADHF).

Methods and results: Forty-four patients hospitalized for ADHF were blindly randomized by using block method to a low sodium diet (LS: 3 g/day of dietary sodium chloride; n = 22, 59.5 ± 11.9 y.o., 50% males. LVEF = 30.0 ± 13.6%); and a normal sodium diet (NS: 7 g/day; n = 22, 56.4 ± 10.3 y.o., 68% males; LVEF = 27.8 ± 11.7%), and both groups were submitted to fluid restriction of 1.000 mL/day. At the 7th day of intervention 16 patients of LS group and 15 patients of NS group were assessed for difference in serum sodium. Both groups had equivalent decongestion, reflected by similar percent reduction of body weight (LS: -5.0 ± 4.7% vs NS: -4.5 ± 5.2%. p = 0.41). Reduction of the N terminal fragment of type B natriuretic peptide (NT-proBNP) was significant only in the NS (-1497.0 [-18843.0 - 1191.0]. p = 0.04). The LS group showed lower levels of serum sodium (135.4 ± 3.5 mmol/L) compared to the NS group (137.5 ± 1.9 mmol/L; p = 0.04). Four cases of hyponatremia were observed only in the LS group (22%). The NS group exhibited higher mean blood pressure values (79.4 ± 2.4 mmHg vs 75.5 ± 3.0 mmHg. p = 0.03), and lower heart rate (73.2 ± 1.6 bpm vs 75.5 ± 2.1 bpm. p = 0.02).

Conclusions: These results suggest that a normal sodium diet, when compared to a low sodium diet, is associated with similar degrees of decongestion, but with higher levels of natremia, blood pressure and lower neurohormonal activation during ADHF treatment.

Trial registration: clinicaltrials.gov Identifier no. NCT03722069.