Whereas evidence supporting the diagnostic value of cardiovascular magnetic resonance (CMR) has increased, there exists significant worldwide variability in the clinical utilization of CMR. A recent study demonstrated that CMR is represented in the majority of European Society for Cardiology (ESC) guidelines, with a large number of specific recommendations in particular regarding coronary artery disease. To further investigate the gap between the evidence and clinical use of CMR, this study analyzed the role of CMR in the guidelines of the American College of Cardiology (ACC) and American Heart Association (AHA).
Twenty-four AHA/ACC original guidelines, updates and new editions, published between 2006 and 2017, were screened for the terms “magnetic”, “MRI”, “CMR”, “MR” and “imaging”. Non-cardiovascular MR examinations were excluded. All CMR-related paragraphs and specific recommendations for CMR including the level of evidence (A, B, C) and the class of recommendation (I, IIa, IIb, III) were extracted.