Management of Hyponatremia in Heart Failure

BACKGROUND: Asymptomatic or clinically mild hyponatremia commonly occurs in the setting of heart failure, especially among elderly and severely decompensated, fluid-overloaded patients, and is associated with increased morbidity and mortality. Successful detection and treatment of hyponatremia by cardiovascular and advanced practice nurses caring for patients with heart failure are part of multidisciplinary team care. Nurses should be able to detect signs and symptoms of hyponatremia and, even when patients are asymptomatic, initiate appropriate treatment promptly to prevent complications. PURPOSE: In this review, the epidemiology and pathophysiology of hyponatremia in heart failure, and signs and symptoms are described. In patients with heart failure, challenges involved in determining the type of hyponatremia (hypervolemic, hypovolemic, or euvolemic) and in correctly managing hyponatremia to prevent serious complications are presented. Conventional treatment options and their limitations are reviewed, and the vasopressin-receptor antagonist tolvaptan, an emerging oral therapy option, is introduced and discussed. CONCLUSIONS: Hyponatremia is a marker of morbidity and mortality in patients with heart failure. Nurses working collaboratively with other healthcare providers must be able to recognize the condition and understand treatment options, including potential adverse effects of current and emerging therapies. One emerging therapy--tolvaptan--can be used in hypervolemic and euvolemic hyponatremic patients with heart failure to correct serum sodium level without negatively affecting renal function. CLINICAL IMPLICATIONS: Improved nurse understanding of hyponatremia in patients with heart failure may promote nurse-initiated or nurse-facilitated detection and management, which could decrease mortality and morbidity.