Mirriam asked me a question with regards to sodium levels in people with congestive cardiac failurei did some reading and thought the following info may be useful for those doing Gen med. The question Mirriam asked was:"in decompensated congestive cardiac failure, is the sodium status high or low?" The answer will likely be that the sodium levels are low especially in the case of decompensated cardiac failure. This answer seems to be contradictory to what we've learnt:CCF --> decreased renal perfusion --> activation of Renin-Angiotensin-Aldosterone pathway --> Aldosterone induces Na+ retention (and subsequent fluid retention) with consequent loss of K+However, other mechanisms:1. CCF --> atrial stretch --> ANP --> sodium loss 2. RAAS/peripheral baroreceptors --> posterior pituitary gland secretes ADH --> favours water retention alone3. Increase Sympathetic Nervous System Activity --> favours water retention alone These favours a significantly increased level of water retention relative to sodium retention.The end result is the patient being in a state of hyponatremia. However, the story does not end here. Hyponatremia's significance as a predictor of mortality is frequently ignored by physicians. Its a pity because recent studies by the American College of Cardiology found out that:1. 1/4 of patients with severe heart failure have hyponatremia2. people with CCF with hyponatremia are 2 times more likely to die than those without hyponatremia in a period of 60 days Perhaps we should consider ditching this ignorance as our patients will certainly benefit since:1. Sodium levels can be easily obtained with U/E/Cr2. Low sodium levels are potentially treatable (no not by fluid loading them with more normal saline, but there are drugs like Tolvaptan which may be available in the future) Anw thats my 2 cents' worthThank you for your kind attention =) Youjiang