Radionuclide assessment of myocardial fatty acid metabolism by PET and SPECT.

Although fatty acid is a major energy source in the normal myocardium, fatty acid oxidation is easily suppressed in a variety of cardiac disorders. Therefore assessment of fatty acid metabolism may hold an important role for early detection of myocardial abnormalities and provide insights into cardiac pathologic states. C-11 palmitate is a well-established PET tracer to probe myocardial fatty acid metabolism. On the other hand, a variety of iodinated fatty acid compounds have been introduced for assessment of fatty acid metabolism with conventional gamma cameras. These include straight-chain, such as iodopheyl pentadecanoic acid (IPPA), and branch-chain fatty acid compounds, such as beta-methyl iodopheyl pentadecanoic acid (BMIPP). This review article includes the characterization of these tracers and clinical experiences with these tracers for detection and characterizing patients with ischemic heart disease and cardiomyopathy.