Nitrogen-13 ammonia perfusion imaging: relation to metabolic imaging

PET provides an advanced imaging technology that permits the accurate definition of regional tracer distribution. In combination with N-13 ammonia, PET allows for the sensitive and specific detection of coronary artery disease. Results of several studies indicate the superiority of this approach compared with standard thallium-201 tomographic imaging. In addition, regional blood flow can be accurately measured with N-13 ammonia PET, and this approach can be used in conjunction with pharmacologic stress imaging to quantify regional flow reserve. In combination with metabolic markers, N-13 ammonia is capable of assessing myocardial viability. Furthermore, the N-13 ammonia PET approach may differentiate among various forms of cardiomyopathy. More studies are needed to define the cost-benefit ratio of the N-13 ammonia PET technique for the management of patients with coronary artery disease or cardiomyopathy.