The Sunnybrook Cardiac Dataset, also known as the 2009 Cardiac MR Left Ventricle Segmentation Challenge Dataset, is used for heart disease research and consists of 45 images from patients and case samples, including healthy, hypertrophic, myocardial infarction, and heart failure. This dataset was released by the National Institutes of Health in 2003, and the relevant paper is "Normal human left and right ventricular dimensions for MRI as assessed by turbo gradient echo and steady-state free precession imaging sequences".