Background and objective; In prior studies, clinical practice guidelines developed by several organizations were slowly and inconsistently applied in clinical practice, and certain evidence-based, guideline-driven heart failure (HF) therapies were significantly underused. The purpose of this study is to survey the guideline compliance of the cardiologists in the treatment of systolic HF and to investigate the consequence of adherence to care by cardiologists on the rate mortality and hospitalization in Korea. Method; The SUGAR trial is a multi-center, retrospective observational study on the clinical information of heart failure from 24 university hospitals cross Korean regions (clinical trial registration with www.clinicaltrials.gov; identifier NCT01390935). Total target was 1509 patients, which subject to participate in the study recruit regional participants as a representative to standard population distribution from Korean national census in 2009. Inclusion criteria were (i) age ��� 20, (ii) subjects admitted to hospital with systolic heart failure (LVEF under 45%) in 2009, (iii) subjects admitted to hospital with dyspnea and verification of heart failure. Patients who expired during hospitalization were excluded. We examined clinical outcomes by medical record at 1 year after first admission. Primary outcome was an adherence indicator which was defined as modified guideline adherence Indicator (mGAI-3) on the basis of the 3 proven pharmacological classes (ACEI or ARB, proven beta blockers and aldosterone antagonist) and mGAI-3 expressed as mean percentage of prescribed 3 each drug. Secondary outcomes were percentage of patients with each class drug prescribed, percentage of patients with daily target dose reached, all cause mortality and rehospitalization. Analysis will be performed to examine real incidence of adherence and the relationship between quality of care and outcomes. Conclusion; This trial is powered to provide robust clinical information for guideline adherence for treatment of systolic heart failure in Korea.