Chloride in Heart Failure: The Neglected Electrolyte.

The increasing burden of heart failure (HF) and emerging knowledge regarding chloride as a prognostic marker in HF have increased the interest in the pathophysiology and interactions of chloride abnormalities with HF-related factors and treatments. Chloride is among the major electrolytes that play a unique role in fluid homeostasis and is associated with cardiorenal and neurohormonal systems. This review elucidates the role of chloride in the pathophysiology of HF, evaluates the effects of treatment on chloride (eg, diuretic agents cause higher urinary chloride excretion and consequently serum hypochloremia), and discusses recent evidence for the association between chloride levels and mortality.