Background: Patients with acute decompensated heart failure (ADHF) face a substantial risk of in-hospital mortality and rehospitalization. We evaluated clinical characteristics and outcomes for the patients with ADHF. Methods: This was a retrospective analysis of observational patient data. Between Oct 2002 & June 2005, 178 patients with ADHF were included. We defined ADHF as a new onset or decompensation of chronic, established HF with symptoms sufficient to warrant hospitalization. Initial data including the clinical characteristics, patterns of care, and outcomes of these patients were analyzed using an ADHERE study profiles. The blood BNP (Triage짰) level (initial & early period;< 30 day) and clinical profiles were analyzed. Poor outcome was defined as readmission due to HF and cardiovascular death. Results: Mean follow-up duration was 19.2 months. Mean age was 69짹13 and male was 61%. Most frequent etiology was ischemic heart disease (38.7%) and most common precipitating factor was myocardial ischemia (43.3%). NYHA class was 2.97짹0.82. The mean length of hospital stay was 7.5짹8.1 days. During hospitalization, 45 (25.3%) of these cases received IV nitrate and 11 (6.2%) for IV dobutamine. Baseline BNP level was 1425짹1224 and early BNP (mean 14.9 days) was 739짹1070 pg/ml. During the follow-up period, poor outcome was developed in 48 patients (27%) including 9 (5.1%) of in-hospital death and 39 (21.9%) of readmission due to HF. In univariate analysis for poor outcome, BUN (p=0.005), Cr (p=0.017), log BNP (p=0.046), early log BNP (p=0.000) and diastolic BP (p=0.057) were significant parameters. Other risk profiles (serum Na, EF, male, NYHA, etc) were not significant correlation with poor outcome. Also, in multivariate analysis, log BNP (p=0.001) was the only independent predictor of poor outcome. The best value of early BNP with the highest sensitivity (68.6%) and specificity (65.4%) for prediction of poor outcome was 438.5 pg/ml (AUC=0.696, p=0.001). Conclusion: In ADHF patients, the risk of in-hospital mortality was relatively low, but readmission rate was relatively high. The important risk factor for poor outcome was early BNP level in our study.