Copper-62 ATSM as a hypoxic tissue tracer in myocardial ischemia

Copper-62 labeled diacetyl-bis (N 4-methylthiosemicarbazone) (62Cu-ATSM) has been proposed as a generator produced positron-emitting tracer for hypoxic tissue imaging. To clarify the usefulness of62Cu-ATSM for myocardial ischemia,62Cu-ATSM PET was performed in 7 patients with coronary artery disease. Increased myocardial uptake of62Cu-ATSM was observed (myocardium/blood ratio: 3.09) in one patient with unstable angina, who had increased18F-fluorodeoxyglucose (18F-FDG) uptake under the fasting condition. The other 6 patients, who were clinically stable, did not have increased62Cu-ATSM uptake, although abnormal18F-FDG uptake was seen in 4 patients. This preliminary study suggests that62Cu-ATSM is a promising PET tracer for hypoxic imaging in acute ischemia.