Abstract

BACKGROUND: Diuretic requirements in patients with acute decompensated heart failure (ADHF) and hyponatraemia versus normonatraemia on admission has not been previously explored. METHODS: The Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial dataset was utilised to examine the characteristics and diuretic requirements of patients with ADHF with hyponatraemia or normonatraemia on admission. RESULTS: Patients with ADHF and admission hyponatraemia (n = 103, average Na 130.2 meq/L) had a higher degree of congestion evident in higher frequency of jugular venous distension (JVD) >12 cmH₂O (p = 0.007), 2+ lower extremity oedema (p = 0.001), and higher right atrial pressure (p = 0.007), compared with normonatraemic patients (n = 327, average Na 138.6 meq/L). Despite a similar baseline furosemide dose in both groups (median 200 mg), the hyponatraemia group received higher in-hospital furosemide (280 vs. 200 mg, in both groups, respectively, p < 0.001) which represented a higher percentage of furosemide utilisation relative to baseline, compared with the normonatraemia group (33% vs 0%, in both groups respectively, p = 0.007). With in-hospital diuresis, the Na level of hyponatraemic subjects started significantly increasing at discharge and up to 6 months after randomisation-all relative to baseline. Hyponatraemic patients had significantly lower systolic blood pressure (SBP) longitudinally at multiple time points compared with normonataremic patients, but it did not further decrease despite the higher furosemide dose in the former group. CONCLUSION: Patients with ADHF and hyponatraemia on admission had a higher degree of congestion and required higher doses of furosemide, compared with normonatraemic subjects. The lower Na and SBP in this instance should not lead to withholding or minimising diuretic dosage which should rather be dictated by volume status.