Introduction: MSince the first registers of heart failure ADHERE, OPTIMEd CHF, ACTIVE in CHF, the data analyzed have attributed Hyponatremia to indepen-dent prognostic role. In the last decade, acute heart fa-ilure syndrome has been in the attention of researchers with additional refinement in terms of clinical forms and prognostic parameters in relation to them.

Objective: Analysis of the prognostic role of hypona-tremia, defined as serum at admission ≤134 mEq / l, in acute heart failure, short and medium term, in relation to the clinical form.

Methods: 228 patients with severe AHF forms were enrolled: CDAHF (Chronic Decompensated Acute Heart Failure) Class IV NYHA and non-ACS (Acute Coronary Syndrome) APE (Acute Pulmonary Edema), admitted to the Cardiology Department of the „St. Pantelimon“ Emergency Clinical Hospital from 01.01-31.12.2013; distributed and analyzed according to the clinical form. Prognostic value (PV) of hyponatremia was identified in the short and medium term, in rela-tion to the clinical form, along with other clinical and echocardiographic parameters.

Results: Analysis of the NA at baseline (NaB) does not show statistically significant difference (SS) (p=0.46) between the two forms – patients with APE vs. CDHAF having a higher serum Na value (135.84 +/- 5.70 mEq/l vs. 131.82 +/- 23.54mEq/l). Univariate analysis shows PV for NaB for both forms for both in-hospital mor-tality (IHM), APE (p<0.01), CDAHF cls. IV NYHA (p<0.01); and for 30-day mortality: APE (p=0.001), CDAHF IV NYHA (p=0.02). ROC curve analysis iden-tifies a threshold value for IHM in APE of 131mEq / l (p<0.01) with a sensitivity of 63.64 and a specificity of 85.71, 95% CI 0.647 -0.833, area under the curve 0.748; and for CDAHF IV NYHA of 130mEq / l with sensitivity of 88.89 and specificity 59.65, 95% CI 0.624 -0.785, area under the curve 0.710 and p<0.01. Mul-tivariate analysis showed independent PV for IHM in both CDAHF IV NYHA (p<0.01) and non-SCA APE (p<0.01) for a NaB value of <130mEq/l.

Conclusions: Hyponatremia not only makes it difficult to treat patients with AHF, indifferent to the clinical form, but also has prognostic value. Easily determined, initially and dynamically, this proved useful in asses-sing short and medium-term mortality for both severe AHF forms.