PERICARDIAL EFFUSION

General Considerations   Abnormal amount of fluid in the pericardial space, defined as the space between the visceral and parietal layers of the pericardium Normally contains about 20-50 cc of fluid Fat covers outside of heart and outside of pericardium sandwiching pericardial space between the two layers Normal thickness of pericardium (parietal pericardium and fluid in space) is 2-4 m Clinical Findings   Small effusions frequently produce no symptoms Chest pain or discomfort with a characteristic of being relieved by sitting up or leaning forward and worsened in the supine position\ Syncope Palpitations Shortness of breath, tachypnea Muffled or distant heart sounds, tachycardia Hypotension Jugular venous distension Pulsus paradoxus Decrease in systolic pressure with inspiration of more than 10 mm Hg Rate of accumulation of fluid is proportional to severity of symptoms The faster the fluid accumulates, the more severe the symptoms Requires about 150-250cc before cardiac tamponade occurs About 7-10% of those with pericardial effusion are at risk for developing tamponade Tamponade compresses heart and causes low cardiac output Most effusions do not lead to cardiac tamponade Size of cardiac silhouette is frequently increased Tamponade is rarely seen in association with pulmonary edema in the lungs  Causes   Causes of Pericardial Effusions Cause Remarks Myocardial infarction Most common Collagen vascular disease Especially Lupus Trauma Surgical or accidental Metastatic disease Serosanguinous effusion Tuberculosis Uncommon except in AIDS Viral infection Coxsackie A and B virus Uremia 18% in acute uremia   Other causes Serous fluid or transudate Congestive heart failure Hypoalbuminemia Irradiation Blood (hemopericardium) Rupture of ascending aorta or pulmonary trunk Coagulopathy Fibrin (produces exudate) Pyogenic infection, e.g. staph Uremia More common in chronic renal disease than acute Imaging findings  Conventional radiography Suggestive but not usually diagnostic "Water bottle configuration" is symmetrically enlarged cardiac silhouette Major DDX is cardiomegaly Loss of retrosternal clear space Non-specific and frequently not valid "Fat-pad sign" Produced by separation of retrosternal from epicardial fat line >2 mm Uncommon but specific Rapidly enlarging cardiac silhouette with normal pulmonary vascularity Echocardiogram Study of choice Echo-free fluid between the visceral and parietal pericardium Early effusions accumulate posteriorly first > 1cm is usually defined as a “large” effusion CT May detect small effusions (50cc) Fluid-filled space surrounding the myocardium Early effusions accumulate posteriorly first  Treatment  Medical treatment depends on cause and may include Non-steroidal anti-inflammatory agents Colchicine Steroids Antibiotics Chemotherapeutic agents Pericardiocentesis Pericardial sclerosis for recurring effusions Tetracycline, doxycycline, 5-fluorouracil Pericardial window Video-assisted thoracic surgery (VATS) Allows for wide resection of pericardium

 

 

 

 

Pericardial effusion on both frontal chest radiograph and axial CT. Red arrow points to fat outside of pericardium. Green arrow points to pericardial space which is 8 mm in this patient (<4 mm is normal.)  The  yellow arrow  points to fat outside of heart and the blue arrow to the myocardium.

 

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