The Korean Acute Heart Failure (KorAHF) registry is a prospective multicenter cohort study designed to describe patient demographics, clinical characteristics, current treatments, and short-term and long-term patient outcomes of AHF. Detailed information on the study design and results from interim analysis are described in our previous paper.20) (link) Briefly, patients who had signs or symptoms of HF and met one of the following criteria were eligible for this study: 1) lung congestion or 2) objective left ventricular systolic dysfunction or structural heart disease findings. Patients hospitalized for AHF from one of 10 tertiary university hospitals throughout the country were consecutively enrolled from March 2011 to February 2014. Follow-up of the patients is planned until 2018. Data were collected by each site and entered into a web-based case-report form in the web-based Clinical REsearch and Trial (iCreaT) system from the Korea National Institute of Health. Information about patient demographics, medical history, signs, symptoms, laboratory test results, electrocardiogram, echocardiography, medications, hospital course, and outcomes was collected at admission, at discharge, and during the follow-up (30-day, 90-day, 180-day, 1- to 5-year annually). In-hospital mortality and the mode of death were adjudicated by an independent event committee. The mortality data for patients who were lost to follow-up was collected from the National Insurance data or National Death Records. The study protocol was approved by the ethics committee/institutional review board at each hospital.