Magnetic resonance imaging of cardiac tumors: part 1, sequences, protocols, and benign tumors.

Cardiovascular magnetic resonance imaging (CMRI) is the reference noninvasive technique for assessment and characterization of a suspected cardiac or juxta-cardiac mass. The multiplanar assessment of anatomy, tissue composition, and functional impact afforded by CMRI allows for early differentiation between a nonneoplastic mass and a tumor mass, be it benign or malignant. CMRI has superior tissue contrast resolution compared with competing noninvasive imaging modalities (echocardiography and multidetector computed tomography). A number of different imaging sequences are employed for a comprehensive CMRI assessment. Black-blood prepared sequences are mainly used for tissue characterization and assessment of lesion enhancement characteristics. Bright blood prepared sequences provide functional information, such as lesion mobility and impact on adjacent valves and chambers. Atrial myxoma is the most common primary benign cardiac tumor and can present with obstructive or embolic phenomena. Fibroelastomas are smaller lesions that do not alter hemodynamic function but can cause symptoms secondary to systemic embolization. Less common benign cardiac tumors include lipoma, fibroma, hemangioma, paraganglioma, and cystic tumor of the atrioventricular nodal region.