Thallium myocardial imaging is a useful technique to evaluate myocardial perfusion and myocardial viability in ischemic heart disease. However, myocardial imaging using single photon emission computed tomography (SPECT) and gamma-emitting radiopharmaceuticals has been recently developed for more precise evaluation of myocardial infarction and ischemia. The present study evaluates animal experiments and the clinical applications of these new myocardial imaging techniques. Areas considered on 1) myocardial necrosis assessed using 111In-antimyosin, 2) myocardial fatty acid metabolism assessed using 123I-beta-methyl-iodophenyl pentadecanoic acid (BMIPP) and 3) myocardial sympathetic neural activity assessed using 123I-metaiodobenzyl guanidine (MIBG). Dual energy SPECT using these new agents and thallium gives precise characterization of the myocardial tissue in the infarcted and ischemic area.