Cardiac neuronal imaging at the edge of clinical application.

Cardiac neuronal innervation plays an important role in normal cardiac function and is adversely affected in the presence of disease. In particular, radiotracer imaging of cardiac sympathetic function has been extensively investigated and not only provides a method of assessing the severity of disease but also has repeatedly been shown to be prognostically useful with a potential for helping to guide patient management. SPECT imaging of myocardial uptake of (123)I-mIBG, an analog of the sympathetic neurotransmitter norepinephrine, has been the most studied, but PET neurotracers, such as (11)C-HED, are also under investigation. The ability of cardiac neuronal imaging to visualize and measure underlying molecular processes should allow it to provide a perspective on cardiac disease that other testing modalities cannot.