Cardiac MRI is a widely accepted modality for characterizing pericardial effusions (loculated vs. hemorrhagic), distinguishing constrictive pericarditis (CP) from restrictive cardiomyopathy (RCM), and delineating pericardial masses.  Aetna Policy 0520 (CMR) cites “pericardial disease” as an indication in which CMR is considered medically necessary.  Cigna Policy 0168 (CMR) also cites “disease of the pericardium” as an indication of medical necessity for CMR.

Accurate diagnosis of pericardial disease is a well-recognized clinical challenge.^Reference   MRI remains the gold standard for comprehensive imaging of pericardial disease.^Reference

• Cardiac MRI provides superior soft tissue and pericardial anatomic characterization.^Reference
• MRI provides superior tissue characterization relative to both CT and echocardiography.^Reference
• Detailed anatomic characterization of the pericardium provided by CMR has aided in determining the etiology of pericardial pathology.^Reference

Cardiac MR should be used when findings on echocardiography are difficult to interpret or conflict with clinical findings.^Reference

Pericardial Masses

Characterization of pericardial masses, especially identifying and/or differentiating their infiltration of adjacent structures, is often difficult. Cardiac MR is the imaging modality of choice when evaluating pericardial masses.^Reference MRI provides superior evaluation of pericardial masses because of its capacity for tissue characterization and high spatial resolution.^Reference

Pericardial Effusion and Tamponade

CMR provides more detailed quantification and localization of pericardial effusion than Transthoracic Echocardiography (TTE), and is especially useful to guide pericardiocentesis, since loculated or regional effusions or regions of calcified pericardium can be identified. When hemopericardium complicates aortic dissection, CMR can readily identify the 2 diagnoses, thereby preventing inappropriate and potentially catastrophic pericardiocentesis. Real-time cine CMR imaging can also provide information similar to TTE with respect to interventricular septal (IVS) motion and chamber collapse.^Reference

CMR is a useful adjunct to TTE for characterizing pericardial effusion and tamponade, in situations in which the hemodynamics are atypical and the presence and severity of tamponade are less certain.^Reference

Constrictive Pericarditis

CMR can show indications for Constrictive Pericarditis similar to those shown by CT, including an elongated and narrowed right ventricle, right atrial enlargement, and abnormal septal motion. Because the pericardium is outlined by fat and lung tissue, accurate measurement of pericardial thickness using CMR is clinically feasible with a reported accuracy of 93% when the pericardium is >4 mm thick. Abnormal diastolic septal motion on CMR yields a sensitivity of 81% and a specificity of 100% for the diagnosis of Constrictive Pericarditis. CMR can be used to evaluate adherence and immobility of the pericardial-myocardial interface.^Reference

Effusive Constrictive Pericarditis can be readily demonstrated with Cardiac MRI with combined elements of pericardial effusion, a thickened pericardium, and hemodynamic evidence of constrictive physiology.^Reference

References:

Yared K, Baggish AL, Picard MH, Hoffmann U, Hung J. Multimodality Imaging of Pericardial Diseases . J Am Coll Cardiol Img. 2010.

Grizzard JD, Ang GB. Magnetic resonance imaging of pericardial disease and cardiac masses. Heart Failure Clinics. 2007.