<qa>  What is the cause of heart failure?Heart failure HF is a major cause of morbidity and mortality world wide. Glucagon-like peptide-1 GLP-1 is an incretin hormone that regulates plasma glucose, and has direct effects on the cardiovascular system. In our previous study, the GLP-1 analogue liraglutide could improve left ventricular function in patients with acute myocardial infarction. However, the effects of GLP-1 on chronic heart failure patients with type 2 diabetes remain unclear. The aim of this study was to evaluate the effects of liraglutide on left ventricular function in chronic heart failure patients with type 2 diabetes. 