Pericardial effusion

  • Normal fluid 15 – 35 ml
  • > 50 ml is abnormal
  • Cardiac failure, renal or hepatic insufficiency, bacterial, viral or fungal infection, neoplasia (lung, breast or lymphoma)
  • Chest Xray
    • Seen only when 200 ml of fluid present
    • Symmetric enlargement of cardiac silhouette resulting in flask like configuration
    • Cardiophrenic angles become acute
    • Curvilinear lucency along left hear border
    • Lateral view: loss of retrosternal clear space. Fluid separates substernal fat from epidural fat
  • ECHO
    • Primary investigation
    • Small amount fluid seen as thin anechoic area in systole behind left ventricle free wall
    • Limited in obesity
    • False positive due to atelectasis, pleural effusion, anterior epicardial fat
    • Common sites of fluid accumulation (gravity dependent): posterolateral wall of left ventricle, inferolateral to right ventricle, superior pericardial recess
  • CT/MR
    • Best demonstrates loculated effusion, hemorrhage, inflammation, thickening
    • Distance between pericardial leaflets > 4 mm is abnormal
    • Moderate effusion if 5 mm or more anterior to right ventricle
    • T1 hypointense, T2 hyperintense
    • T1 hyperintense if protein rich
    • GRE shows blood products
    • Pericardial thickening, leaflet enhancement points to inflammation/neoplasia. Nodularity favors neoplasia
Cardiac tamponade
  • Severe acute effusion compressing cardiac chambers
  • Limits ventricular filling 
  • Decreases cardiac output 
  • ECHO: right atrial compression, diastolic collapse of right ventricle free wall, increased variation of mitral and tricuspid diastolic blood flow velocities, abnormal right-sided venous flow, decreased IVC collapsibility in inspiration
Read more

Wang, Zhen J., et al. “CT and MR imaging of pericardial disease.” Radiographics 23.suppl_1 (2003): S167-S180.

Restrepo, Carlos S., et al. “Primary pericardial tumors.” Radiographics 33.6 (2013): 1613-1630.

Restrepo, C. Santiago, et al. “Imaging findings in cardiac tamponade with emphasis on CT.” Radiographics 27.6 (2007): 1595-1610.