Background: Heart failure (HF) is a major public health problem. In Chile hospitalized patients due to HF have not been. characterized. Aim: 76 evaluate clinical profile and outcome of patients hospitalized for heart failure in Chilean hospitals. Patients and Methods: Prospective registry of 14 centers. Patients hospitalized,for HT in functional class III and IV were included. Epidemiological and clinical data, functional class, type of presentation, decompensation cause, electrocardiogram, echocardiogram, treatment and evolution were registered. Results: Three hundred seventy two patients aged 69+/-73 years old, 59% men, were assessed. The main etiologies of HF have ischemic in 31.6% hypertensive in 35.29%, valular in 14.9% and idiopathic in 7.4%. There was a history of hypertension 69%, diabetes in 35%, myocardial infarction in 22%, atrial fibrillation in 28%. The presentation form of HF was chronic decompensated in 86%, acute in 12% refractory in 29%. The causes of decompensation were non compliance with diet or medical prescriptions in 28%, infections in 22% and AF 17%. ECG showed AF in 36% and let bundle branch block in 16%. Echocardiography was performed in 52% of the patients, 69% bad left ventricular ejection fraction <40%. On admission, 39% received angiotensin converting enzyme (ACE,) inhibitors, 15% beta-blocker; 2596 digoxin, 16% spironolactone and 53% furosemide. The mean hospital stay was 11+/-10 days and mortality was 4.5%. Conclusions: The elderly is the age group most commonly admitted to hospital due to HF. The main etiologies were ischemic and hypertensive. The main causes,for decompensations were noncompliance with, diet or medical prescriptions and infections. A significant proportion bad a relatively well preserved ventricular systolic function.