Myocardial Perfusion Imaging Theory

Abstract The concept of injecting a tracer into the blood stream and detecting its transit and distribution in the heart muscle for the assessment of myocardial perfusion is well established in nuclear cardiology and cardiovascular magnetic resonance (CMR). Both exogenous, injected contrast agents and endogenous contrast mechanisms have been used to assess perfusion with CMR. The use of a gadolinium (Gd)-based contrast agent for the assessment of myocardial perfusion with CMR has been extensively validated and successfully applied in patient studies. Developments, in particular the introduction of parallel imaging, and sparse sampling methods, have made it possible to combine the requirements for spatial and temporal resolution for myocardial perfusion imaging during the first pass, with multi-slice coverage of the heart. The need for a quantitative, largely observer-independent analysis of perfusion studies has also received increasing support. Several approaches have been developed that allow quantification of myocardial blood flow (MBF) with CMR. Advances in rapid imaging techniques for CMR perfusion imaging and the development of methods to obtain reproducible, quantitative measures of myocardial perfusion have established CMR perfusion imaging as an attractive alternative to nuclear perfusion imaging.