Relation between regional myocardial uptake of rubidium-82 and perfusion: Absolute reduction of cation uptake in ischemia

ASNC imaging guidelines/SNMMI procedure standard for positron emission tomography (PET) nuclear cardiology procedures

“…82 Rb extraction can be decreased by severe acidosis, hypoxia, and ischemia. [35][36][37] Thus, while uptake of 82 Rb predominantly depends on MBF, it may be modulated by metabolism and cell membrane integrity.…”

The Clinical Value of Myocardial Blood Flow Measurement

“…The generatorproduced cationic potassium analog 82 Rb represents an attractive alternative because it does not require a cyclotron on-site and has a short half-life (78 s). Early experimental studies have shown that, although 82 Rb with PET allows detection of myocardial ischemia, quantification of MBF using this tracer is limited by the heavy dependence of its myocardial extraction at higher flow rates (66). Because the myocardial extraction of 82 Rb decreases significantly with increasing flow rates, the calculated hyperemic flow with vasodilator stress may underestimate the actual flow rate.…”

Delineation of impaired regional myocardial perfusion by positron emission tomography with H2(15)O.

“…Because extraction and retention of both tracers are influenced by the metabolic states of myocardium, as well as by perfusion, 1,3,5,6,[8][9][10] these tracers can be used to evaluate myocardial meta-bolic activity, as well as flow,6 if enough tracer can be delivered to the myocardial segment in question.…”

“…Single-pass extraction and myocardial retention of`3N-labeled ammonia are influenced by flow23,8 as well as by cell membrane integrity9 and the metabolic state of the myocardium.8 9 Extraction of 82Rb also varies with flow and metabolism. 5,6,10 An ideal perfusion tracer should be either freely diffusible or completely extractable and retainable by myocardium on a single pass through the coronary circulation without having its kinetics altered throughout the range of flow studied or by the metabolic status of the myocardium. 150-labeled water (H2`50) is essentially a freely diffusible tracer in the heart with uptake that does not vary despite wide variations in flow rate11 or changes in the metabolic state of myocardium associated with prolonged ischemia or reperfusion.…”