rubidium-82

Rubidium-82 (82Rb) is a radioactive isotope of rubidium. 82Rb is widely used in myocardial perfusion imaging. This isotope undergoes rapid uptake by myocardiocytes, which makes it a valuable tool for identifying myocardial ischemia in Positron Emission Tomography (PET) imaging. 82Rb is used in the pharmaceutical industry and is marketed as rubidium-82 chloride under the trade names RUBY-FILL and CardioGen-82.

==History== In 1953, it was discovered that rubidium carried a biological activity that was comparable to potassium. In 1959, preclinical trials showed in dogs that myocardial uptake of this radionuclide was directly proportional to myocardial blood flow. In 1979, Yano et al. compared several ion-exchange columns to be used in an automated 82Sr/82Rb generator for clinical testing. Around 1980, pre-clinical trials began using 82Rb in PET. In 1982, Selwyn et al. examined the relation between myocardial perfusion and rubidium-82 uptake during acute ischemia in six dogs after coronary stenosis and in five volunteers and five patients with coronary artery disease. Myocardial tomograms, recorded at rest and after exercise in the volunteers showed homogeneous uptake in reproducible and repeatable scans. Rubidium-82 has shown considerable accuracy, comparable to that of 99mTc-SPECT. In 1989, the FDA approved the 82Rb/82Sr generator for commercial use in the U.S. With increased 82Sr production capabilities, the use of 82Rb has increased over the last 10 years and is now approved by several health authorities worldwide.