Cardiac positron emission tomography (PET) with generator-produced rubidium-82 (Rb-82) provides information not previously available for optimal diagnosis and management of cardiac disease. This new information includes the accurate, noninvasive diagnosis of coronary artery disease in asymptomatic or symptomatic patients, the noninvasive assessment of coronary stenosis severity, myocardial infarct imaging, myocardial viability, collateral function, and cardiomyopathy. Cardiac positron imaging may be carried out economically at the same or less cost as other high-tech diagnostic imaging but provides perfusion and metabolic information quantitatively for routine clinical studies not available by other diagnostic modalities.