Spin echo MRI in the evaluation of pericardial disease

As in other pathological processes of the heart, the contribution of MRI is not limited to optimal anatomical evaluation but also offers functional or etiological information (approach of tissue characterization). In this work we report on our experience in evaluating normal and pathological pericardium with MRI spin echo sequences. The results with 41 patients, including pericardial effusion, thickening, and mass are discussed and confronted with previously reported data. Contrary to classical echocardiographic notions, pericardial effusions are more frequently in the anterior than posterior location (26/30 vs. 19/30 p less than 0.03). Not only does MRI provide a precise and positive diagnosis, but also a rather clear distinction appears in spin echo sequences between hemopericardium with high signal intensity and other effusions with lower signal (high intensity found in 6/6 patients with hemopericardium versus only 8/24 in the remaining group; p less than 0.01). When constriction signs are present, MRI solves the difficult differential diagnosis between pericardial thickening and restrictive cardiomyopathy. In paracardiac primary or metastatic tumors pericardial involvement is clearly demonstrated. Distinction between paracardiac, respectively pericardial cyst or false aneurysm is possible. We conclude that MRI is a new imaging method, complementary to echocardiography and/or computed tomography in the evaluation of pericardial pathology especially when hemopericardium, constrictive pericarditis, or tumoral etiologies are suspected. Important technological improvements are needed to solve the problem of long acquisition time and to improve the possibilities of tissue discrimination.