Electrolyte Imbalance and Outcomes in Heart Failure

Electrolyte disturbances are a hallmark of heart failure, arising from a combination of neurohormonal activation, impaired renal function and the widespread use of diuretics. Hyponatraemia, hypokalaemia and hypochloraemia each correlate with worsened functional status, higher rates of arrhythmia and increased hospital readmission. Alterations in serum osmolality further reflect the delicate balance between volume status and solute concentration, and both hypo- and hyperosmolar states have been linked to early mortality. Beyond patient-level implications, these derangements have global significance: they complicate management in low-resource settings and contribute substantially to the health-economic burden of heart failure. Emerging evidence has begun to integrate electrolyte profiling into risk stratification and therapeutic algorithms, underscoring the need for routine monitoring and tailored intervention to improve prognosis and reduce rehospitalisation.

Research from Nature Portfolio

A retrospective cohort of acute heart failure patients examined the prognostic value of urinary chloride excretion. Patients with low urinary chloride (<115 mmol/L) experienced higher in-hospital mortality, greater need for inotropic support and more frequent intensive care admissions. Over one year, low chloride excretion independently predicted both mortality and rehospitalisation, suggesting that urinary chloride may serve as a practical biomarker of congestion severity and renin–angiotensin–aldosterone system activation beyond traditional clinical indices.

Electrolyte Imbalance and Outcomes in Heart Failure publication trend

The graph below shows the total number of articles in electrolyte imbalance and outcomes in heart failure across all publications each year (not limited to Nature Index journals).

Technical terms

Hyponatraemia: A serum sodium concentration below 135 mmol/L, often arising from fluid overload, diuretic use and vasopressin-driven free-water retention in heart failure.

Hypochloraemia: Low serum or urinary chloride levels, reflecting diuretic use and neurohormonal activation; linked to greater congestion and worse outcomes.

Serum osmolality: The total concentration of solutes in the blood, expressed in mmol/kg; extremes of osmolality predict early mortality in heart failure.

Neurohormonal activation: The enhanced release of hormones such as renin, angiotensin II and aldosterone in response to low cardiac output, driving fluid retention and electrolyte shifts.

Congestion: The accumulation of fluid in tissues and the circulation due to impaired cardiac pumping, often manifesting as peripheral oedema, pulmonary rales and elevated jugular venous pressure.

Heart failure with reduced ejection fraction (HFrEF): A subtype of heart failure characterised by impaired left ventricular contraction (ejection fraction ≤40%), often accompanied by distinctive electrolyte and fluid-management challenges.

References

1. The role of urine chloride in acute heart failure. Scientific Reports (2024).
2. Association between serum osmolality and 28-day all-cause mortality in patients with heart failure and reduced ejection fraction: a retrospective cohort study from the MIMIC-IV database. Frontiers in Endocrinology (2024).
3. Medical Treatment in Heart Failure with Reduced Ejection Fraction: A Proposed Algorithm Based on the Patient’s Electrolytes and Congestion Status. Medical Sciences (2023).
4. Relationship between serum sodium levels and all-cause mortality in congestive heart failure patients: A retrospective cohort study based on the Mimic-III database. Frontiers in Cardiovascular Medicine (2023).