Cardiac Positron Emission Tomography Myocardial Perfusion Imaging: Seeing Beyond Perfusion.

Positron emission tomography (PET) myocardial perfusion imaging (MPI) is a highly accurate noninvasive modality for evaluating coronary artery disease due to its excellent sensitivity and specificity, excellent image quality, efficient imaging protocol, and significantly lower radiation exposure. Its ability to absolutely quantify myocardial blood flow (MBF), MBF-R, and left ventricular ejection fraction-reserve also strengthens its diagnostic and prognostic properties and guides physicians about the justification for coronary revascularization. Presence of coronary artery calcification on the CT component indicates atherosclerosis, and its presence with normal PET MPI indicates subclinical nonobstructive coronaries and warrants risk factor medication to avoid future major adverse cardiac events. Metabolic imaging with FDG PET is considered the gold standard for diagnosing hibernating myocardium and helps in the management of sarcoidosis and infection of the cardiovascular system and implanted devices. However, the huge upfront and operational costs are the primary factors for the limited availability of PET MPI.