Design of Radioprobes for Pet and Spect Imaging

Nuclear Cardiology is an important and non-invasive tool for the clinical evaluation of patients with known or suspected coronary artery disease (CAD), one of the leading causes of death in western countries. The advancement of this field depends on the continuous improvement and development of equipment and signal processing technologies. However, its success is primarily determined by the design and development of new radiopharmaceuticals suitable for Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET) imaging. Nuclear cardiology started in the mid-1970s with the use of Tl-201-thallous chloride, which has been the firstly approved radiopharmaceutical for perfusion cardiac imaging. Later on, Tc-99m-Sestamibi was introduced and approved for clinical use. Nowadays, Tc-99m-Sestamibi is the most used radioprobe for SPECT cardiac imaging. In the case of PET, nuclear cardiology still relies mainly on the use of [F-18]-2-fluoro-2-deoxy-glucose, which is the gold standard metabolic tracer for cardiac imaging. Until now, a variety of other SPECT and PET radioprobes have been tested as radiopharmaceuticals for cardiac imaging. This contribution reviews representative examples of the chemical/radiochemical strategies that have been used to design perfusion and target-specific radiopharmaceuticals for cardiac imaging.