Myocardial perfusion imaging is a major pillar of cardiological diagnostics in the field of nuclear medicine. PET-based assessments using Rb-82 as a tracer outperform conventional scintigraphic methods by offering absolute flow measurements; with this additional information, perfusion assessment becomes accessible for inexperienced users. This study primarily shows high inter-observer reliability of the method, enhancing its role as a robust tool among all levels of experience. Second, it demonstrates the reliability of measuring left-ventricular volumes and ejection fraction in comparison to echographic assessments. The study aims to enhance confidence in the method of myocardial blood flow measurement and left-ventricular volume assessment using Rb-82-PET/CT.