Evaluation of Renal Sodium Excretion After Salt Loading in Heart Failure With Preserved Ejection Fraction

Heart failure (HF) affects 2-3% of the population, and is characterized by impaired sodium balance which results in fluid overload. Ejection fraction, a measure of systolic function, is reduced in only about half of all HF patients. Incidence of heart failure with preserved ejection fraction (HFpEF) has increased in the last 20 years making it a growing public health problem. Currently, most patients admitted to the hospital with heart failure have preserved rather than reduced ejection fractions. However, to date it remains unknown why patients with HFpEF retain salt and water. The hypothesis is that patients with clinical HFpEF have an impaired renal response to salt loading, intravascular expansion and diuretics. Characterization of the salt and water excretory renal response to intravascular salt, fluid and diuretic load in patients with HFpEF will provide insight into the pathophysiology of HFpEF, and may help in the development of novel strategies to target renal sodium handling in patients with HFpEF. This characterization is the primary objective of this pilot project.