Dyshomeostasis of serum sodium concentration in congestive heart failure.

Congestive heart failure (CHF) is the most common discharge diagnosis in the United States and accounts for greater than 1 million hospital discharges annually. CHF is associated with many serum electrolyte abnormalities, the most common and perhaps most significant of which is hyponatremia. CHF with hyponatremia makes the already high morbidity and mortality of CHF even more unfavorable. Further, the usual treatment for CHF with diuretics usually aggravates hyponatremia. Hyponatremia may result in impaired cognition and neurologic performance in a large number of patients, which is usually reversible with correction. The high morbidity and mortality with CHF and hyponatremia are not improved with the usual treatment with diuretics or ultrafiltration. This article provides an overview of the pathophysiology of hyponatremia in CHF. In addition, the authors will explore the various treatment options that are available and the evidence to support their utility.