Heart failure (HF) is a highly prevalent and progressive condition associated with significant morbidity and mortality rates. Acute decompensated HF precipitates millions of hospitalizations each year. Despite therapeutic advances, the overall prognosis of HF is poor. The varying clinical courses and outcomes of patients with this disease may be due to region-specific gaps and since most HF studies are conducted in developed countries, the participation of Latin American and Caribbean countries is low. Considering this, the American Registry of Ambulatory and Acute Decompensated Heart Failure (AMERICCAASS) aims to characterize the population with ambulatory and acute decompensated HF in the American continent and to determine rehospitalization and survival outcomes during the 12 months of follow-up.