Table 1.

Differential diagnosis of cardiac masses based on echocardiographic characteristics

Cardiac mass	Echo findings
Blood cyst	Attached to valve leaflet (most commonly mitral valve). Thin-walled cystic lesion. Echolucent core. May be multilobed. Usually doesn't opacify with use of echo contrast, but if channels are present, contrast may show up in the cyst. May cause valve regurgitation and left ventricular outflow tract obstruction.
Fibroelastoma	Most often found in valves (most commonly aortic valve, may occur in any endothelial structure). Attached to valve by a stalk. “Shimmering” edge. No associated regurgitation or valve destruction.
Myxoma	Most commonly located in the left atrium, followed by the right atrium and usually attached to the atrial septum by a stalk.
Lambl's excrescence	Linear echodensities most commonly seen in the aortic valve at the closure margin of the valve. Considered degenerative process and frequency increases with age. No associated regurgitation or valve destruction.
Vegetation	Mobile mass with independent motion from the structure it is attached to. Usually located in a valve but can also be seen in support structures or prosthetic devices. Typically causes valve destruction and is usually seen in the path of the regurgitant jet. Positive blood cultures support the diagnosis.