In myocardial SPECT imaging with the popularly used 99mTc-sestamibi and 99mTc-tetrofosmin, intense liver uptake leads to a paradoxical decrease of counts in the absence of perfusion abnormalities, making it difficult to assess myocardial perfusion, particularly in the inferior or inferoapical left ventricular wall. 99mTc-N-DBODC5, which is a new lipophilic, mono-cationic nitride myocardial perfusion imaging agent, exhibits high myocardial uptake and excellent biodistribution kinetics with rapid liver clearance in rats and dogs. 99mTc-N-DBODC5 myocardial imaging during vasodilator stress can determine the severity of stenosis, though underestimates occur with mild coronary stenosis compared to 201Tl, in a similar way to what occurs with 99mTc-sestamibi and 99mTc-tetrofosmin. In particular, 99mTc-N-DBODC5s rapid liver clearance, which may significantly reduce the photon scatter from the liver, allows for the reduction of artifactual decreased myocardial perfusion and the improvement of the diagnostic accuracy of coronary artery disease.
Keywords: 99mTc-N-DBODC5., lipophilic mono-cationic nitride, technetium-99m, 99mTc labeled myocardial perfusion agent, myocardial perfusion imaging, single photon emission computed tomography (SPECT), radionuclide imaging, myocardial uptake, rapid liver clearance, liver artifact