Box 2: Comparison of cardiac mass features on transthoracic echocardiography and cardiac magnetic resonance imaging2,3
Imaging modalityThrombusBenign tumourPrimary malignant tumourMetastatic tumour
Transthoracic echocardiography

  • Associated with severe left ventricular dysfunction, atrial fibrillation and mitral valve disease

  • Mobile

  • Connected to the interatrial septum with a stalk (especially with myxomas)

  • Homogenous and hyperechoic (e.g. lipomas)

  • Broad-based

  • Invasion of the myocardium and inferior vena cava

  • Pericardial involvement

  • Pericardial effusion

Cardiac magnetic resonance

  • Low signal intensity on T1- and T2-weighted imaging in chronic thrombus

  • No contrast uptake

  • Well-defined borders

  • Homogeneous

  • Small hemorrhages may be seen within the mass

  • Ill defined with irregular borders

  • > 5 cm

  • Invasion of adjacent tissue

  • Intralesion hemorrhage and necrosis

  • Contrast enhancement

  • Hemorrhagic pericardial effusion

  • Similar to malignant tumours

  • Extra cardiac involvement