A review describing the basic aspects, practical measurements and clinical applications of coronary endothelial function using myocardial perfusion PET in subjects with various coronary risk factors and published online in the Journal of Nuclear Cardiology outlined the utility of PET in this population.
Endothelial dysfunction is the earliest abnormality in the development of coronary atherosclerosis and is also independently associated with future cardiovascular events. Therefore, it is important to detect endothelial dysfunction as doing so may guide early interventions toward reducing the risk of future cardiovascular events, according to Keiichiro Yoshinaga, MD, PhD, associate professor of photobiology at Hokkaido University Graduate School of Medicine in Sapporo, Japan, and co-authors.
The non-invasive aspects and coronary specificity of measurements of myocardial blood flow (MBF) using PET with sympathetic stress make it widely applicable for the evaluation of endothelial function.
PET MBF measurements with sympathetic stress have been applied to a variety of subjects with coronary risk factors and have been shown to have value for risk assessment in these subjects, wrote Yoshinaga and colleagues.
15O-labeled water and 13N-ammonia have most often been employed for MBF quantification to evaluate endothelial function. Recently, generator-produced rubidium-82 (82Rb) has been employed for this measurement. Specific protocols such as pharmacological stress tests, mental stress tests and cold pressor tests have been proposed for endothelial function measurement. However, standard stress protocols should be established, noted the authors.
Endothelial measurement using PET also remains an ideal research tool for the study of the pathophysiology of several cardiac diseases, according to the authors, who added that PET is well-suited for the acute and longitudinal evaluation of treatment. Thus, continued development of this approach to evaluate new treatment effects should be expected, concluded Yoshinaga and colleagues.