Cardiac Perfusion MRI

Cardiac perfusion magnetic resonance imaging (MRI) is used to evaluate blood flow to the myocardium during pharmacologic stress conditions. It is primarily employed in the diagnosis and assessment of coronary artery disease (CAD) and of coronary microvascular disease. Cardiac perfusion MRI provides radiation-free and high-resolution images of the heart and has become one of the methods of choice indicated by present guidelines for the assessment of the perfusion status of the heart. Whilst cardiac perfusion MRI images are normally assessed qualitatively, involving the visual interpretation of the images, automated quantitative analysis is emerging as a viable alternative. Quantitative perfusion analysis involves measuring the actual blood flow to the myocardium, typically in millilitres per minute per gram of tissue [ml/min/g]. This analysis provides more objective and precise measures of myocardial perfusion than qualitative assessment. This chapter discusses the main techniques for quantitative perfusion analysis, including the optimisation of MRI acquisition and post-processing methods, as well as some applications of artificial intelligence and machine learning which have the potential to enhance the accuracy, efficiency and clinical utility of this technique.