The role of cardiac magnetic resonance imaging in cardiology consultation

Cardiovascular magnetic resonance imaging (CMR) has emerged as a powerful, multipurpose, noninvasive imaging modality of great value to cardiac consultants who are asked increasingly to evaluate increasingly complex cases of cardiac anatomy and pathophysiology. CMR, unlike other imaging modalities that require ionizing radiation, is extremely safe and suited for the evaluation of both congenital and acquired cardiac diseases. CMR is the gold standard for the evaluation of global systolic function, abnormal tissue characteristics, and myocardial viability. This chapter will review key fundamental principles in MR physics that form the basis of MR imaging followed by a brief discussion of image acquisition and signal processing that are unique for CMR. Basic CMR pulse sequences and common clinical applications of these sequences will be discussed including the use of flow/velocity encoding sequences in the quantitative analysis of flow and myocardial stress imaging. The chapter will also touch on the common roles of CMR in the assessment of restrictive, dilated, and hypertrophic cardiomyopathies, valvular heart disease, congestive heart failure, myocarditis, cardiac neoplasms, pericardial disease, and congenital heart disease. Technical and patient safety issues will also be reviewed. To date, CMR remains a relatively time-consuming and technically difficult imaging modality and is not commonly available. Future improvement in hardware and software as well as simplifying image post-processing will improve the availability of CMR and allow it to be performed on even more challenging patients.