Can anyone explain why HypoNa in CHF pt is a bad progostic indicator?

[hunteradam07]

I could not get this concept of my cardio question. It said that hyponat in CHF is very bad indicator, because it's associated with neurohumoral increase like ADH, Aldosterone, and NE. I get how ADH makes hypoNa, bt how can Aldosterone would cause hyponat?

[Protoman2050]

I could not get this concept of my cardio question. It said that hyponat in CHF is very bad indicator, because it's associated with neurohumoral increase like ADH, Aldosterone, and NE. I get how ADH makes hypoNa, bt how can Aldosterone would cause hyponat?

Because aldosterone promotes reabsorption of sodium and water. And the water so reabsorbed by the aldosterone and ADH dilutes the reabsorped sodium.

Hyponatremia is associated with fluid overload, which increases the strain on the heart, and can lead to pulmonary edema and cerebral edema.

Read: Managing Hyponatremia in Heart Failure | Cardiology (http://www.touchcardiology.com/articles/managing-hyponatremia-heart-failure)

And: Hyponatremia Predicts Right Heart Failure and Poor Survival in Pulmonary Arterial Hypertension -- Forfia et al. 177 (12): 1364 -- American Journal of Respiratory and Critical Care Medicine (http://ajrccm.atsjournals.org/cgi/content/short/177/12/1364)