Developments in nuclear cardiology: transition from single photon emission computed tomography to positron emission tomography-computed tomography.

Recent advances in positron emission tomography (PET) instrumentation have paralleled those of multichannel computed tomography (CT) for cardiac applications. Whereas multi-channel CT angiography provides information on the presence and extent of anatomical luminal narrowing of epicardial coronary arteries, stress myocardial perfusion PET provides information on the downstream functional consequences of such anatomic lesions. With the advent of hybrid PET/CT systems, such complimentary information of anatomy and physiology can be realized immediately at the same imaging session. By acquiring dynamic, gated myocardial perfusion data, PET studies provide insight into impairment of regional coronary blood flow reserve and microvascular endothelial dysfunction. This paper presents recent developments in PET detector materials, acquisition modes, combined PET/CT scanners, rubidium-82 (Rb-82) gated myocardial perfusion studies and analysis methods for absolute myocardial blood flow quantification.