On cardiac myxoma, CT scan is characterized by low attenuation and areas of dystrophic calcification in cardiac chambers. CT scan may be helpful in the diagnosis of cardiac myxoma, because it provides better soft-tissue contrast than echocardiography, and it can also differentiate calcification and fat, and may allow tissue diagnosis of some masses such as lipomas.
Key CT scan Findings in Myxoma
Cardiac myxomas appear as intra-cardiac masses, most often in the left atrium and attached to the interatrial septum. They are usually heterogeneously low attenuating (approximately two-thirds of cases). Due to repeated episodes of haemorrhage, dystrophic calcification is common.
The contrast–enhanced chest CT findings in cardiac myxoma include:
Low attenuating heterogeneous intracardiac mass
Spherical or ovoid intracavitary mass
CT Examples of Cardiac Myxoma
Two- or three-dimensional echocardiography
Echocardiography is usually the initial modality used for identification and evaluation of cardiac myxomas.
Hyperechogenic lesions with a well-defined stalk.
Protrusion into the ventricles is a common finding.
Tumor mobility and distensibility.
Limited views of the mediastinum and cannot be used to evaluate extracardiac manifestations of disease.
TEE is an invasive imaging technique.
TT is limited by the imaging window, which can vary with the patient and operator experience.
Evaluation of cardiac masses and is of greatest value when echocardiographic findings are suboptimal or when the lesion has an atypical location or appearance.
Cardiac myxomas appear spherical or ovoid with lobular contours, irregular in shape.
T1 : Low to intermediate signal, but areas of hemorrhage may be high.
T1 C+ (Gd): shows enhancement (important discriminator from a thrombus) demonstrates uniform heterogeneous enhancement.
MRI allows imaging in multiple planes.
Provides some functional information such as, flow direction and flow velocity in large vessels.
Cannot show calcification.
High susceptibility to motion artifact.
Dependent on regular electrocardiographic rhythms and cardiac gating.
CT can be used to accurately image the heart and surrounding mediastinum.