Cardiac masses
Cardiac MR (magnetic resonance) imaging holds an important role in the evaluation of suspected cardiac masses. Even early in its development, MR was found to be diagnostically superior to echocardiography for diagnosis of cardiac masses, due in part to the modality’s high spatial resolution and in part to its large field of view, which allowed evaluation of mediastinal and paracardiac structures.
Now, with the development of electrocardiogram (ECG) gating, cine gradient recalled echo and steady state free precession techniques, MR imaging has improved lesion detection with reduced imaging times. Cine MR allows dynamic assessment of cardiac masses as well as their effect on valvular function. Furthermore, with administration of gadolinium, Cardiac MR helps distinguish cardiac masses from intracardiac thrombus and normal myocardium.
Key Points
- While echocardiography provides clear visualization of the left side of the heart, it is limited in its evaluation of the right heart and mediastinal structures. MR can provide clear evaluation of these areas, as well as help to define normal anatomic variants or “pseudotumors” found on echo.
- Metastatic disease to the heart is far more common than primary cardiac tumors. Metastases from lung and breast cancer are common, given their proximity to the heart, and MR can be used to provide important staging information when such lesions are detected. Other common tumors with cardiac involvement include melanoma and lymphoma.
- Tumors such as renal cell carcinoma can spread by transvenous extension, and accurate evaluation of the inferior vena cava (IVC) and right atrium is important in surgical planning for these patients. The IVC can be evaluated by MR images acquired in the coronal and sagittal planes.
- In addition to cardiac masses, MR allows evaluation of complications of these masses. Valvular involvement can be well-visualized on cine images. Pericardial effusions may also be characterized as benign or malignant, with the majority of malignant effusions presenting as hemorrhagic.
- MR can help characterize lesions by detecting fat, fluid, or blood products.
Case in Point
35 year old male with synovial sarcoma. The Cardiac MR using four-chamber views (left) demonstrates a large mass within the apex of the left ventricle which enhances following the administration of gadolinium. The coronal image (right) demonstrates metastatic lesions at the level of the left atrium. Picture of human lungs with cardiac mass in the right lung.
For Further Reading
- Gilkeson RC, Chiles C. MR evaluation of cardiac and pericardial malignancy. Magn Reson Imaging Clin N Am. 2003 Feb;11(1):173-86, viii.
- Araoz PA, Mulvagh SL, Tazelaar HD, Julsrud PR, Breen JF. CT and MR imaging of benign primary cardiac neoplasms with echocardiographic correlation. Radiographics. 2000 Sep-Oct;20(5):1303-19.