CT and MR imaging findings of benign cardiac tumors

Abstract

This imaging review describes the appearance of benign cardiac tumors on CT and MRI. Although rare, benign tumors outnumber their primary malignant counterparts three to one. Since mortality varies directly with invasion, identifying the neoplasm at an early stage helps focus treatment, especially in benign cases, which generally respond well to surgical resection. In adults and children, myxomas and rhabdomyomas, respectively, represent the most common benign tumors, which can be grouped into tissue-specific subtypes, such as rhabdomyomas, fibromas, lipomas, teratomas, etc. Besides their variable prevalence in particular age groups, these tumors also differ with regard to their gender predilection, location, and number. For example, myxomas appear predominantly in women and generally as a solitary mass in the left or right atrium, whereas rhabdomyomas present equally in boys and girls and chiefly as multiple masses in the ventricles. Despite their differences, however, both types share an association with heritable syndromes like the Carney complex for myxomas and tuberous sclerosis for rhabdomyomas. As with all cardiac tumors, echocardiographic findings usually suggest the initial diagnosis but cross-sectional imaging with CT and MRI can help resolve diagnostically challenging cases. For example, with its direct multiplanar capability, excellent contrast resolution, and large field of view, MRI permits a detailed examination of the entire mediastinum, helping to rule out an equivocal mass on echocardiography. Through dynamic techniques, MRI, in addition to morphologic characterization, can depict the pathophysiological effects of these tumors, for instance, with regard to myocardial contraction, valvular function, or blood flow.