Positron emission tomography has become an increasingly alternative
method for clinical application in patients with coronary artery disease. Although,
various myocardial perfusion PET tracers are available, the most commonly used in
clinical setting are Rubidium-82 (82Rb) and nitrogen-13-ammonia (13Ν-ammonia). 82Rb
is a cation and an analog of potassium with kinetic properties similar to those of
Thallium-201. It combines the advantages of a short 75 seconds physical half-life and
its independency of an onsite cyclotron through the availability of a relative small
onsite Strontium-82 / 82Rb generator. Although it is not the ideal tracer for absolute
quantification (first–pass extraction of 65%), it has been used extensively for this
purpose showing valuable data in the clinical setting. 13Ν-ammonia is a cyclotron
product with physical half-life of 9.96 minutes. Due to the combination of the high
first-pass myocardial extraction fraction (80%) and the relatively long physical half-life
of the radiotracer, high-contrast resolution myocardial perfusion images can be
obtained. Oxygen -15-water (15O-water) is used in research studies, mainly for precise
measuring of myocardial blood flow. 18F-Fluripiridaz is a new promising tracer with
excellent biological and imaging characteristics, including longer half-life, availability
in unit doses from regional cyclotrons, low positron range, and high myocardial
extraction. It is now in advanced clinical evaluation with encouraging results. Due to
the short half-life of the radiotracers a PET rest-stress study is obtained in a shorter
time than a single photon emission computed tomography study, while PET myocardial perfusion imaging provides higher diagnostic accuracy, using lower radiation doses
compared to single photon emission tomography.
Keywords: 13Ν-ammonia, 15O-water, 18F-FBnTP, 18F-Fluripiridaz, 18FFluorodihydrorotenone,
18F-FTPP, Coronary artery disease, Myocardial blood
flow, Myocardial perfusion imaging, Positron emission tomography, Rubidium-
82.