"idiopathic (presumed viral, post-viral or immune-related)"
"post-myocardial infarction: Dressler syndrome"
"post-surgical or traumatic"
"However, due to complex pericardial anatomy and fluid being able to pool in the pericardial recesses, this relationship is not exact, and it may be better to report volume in more general terms 10-12,13:"
Expected headings
"Echocardiography"
"Estimating volume"
"systemic inflammatory conditions or connective tissue diseases, e.g. systemic lupus erythematosus, rheumatoid arthritis, scleroderma, Sjögren disease, vasculitis, familial Mediterranean fever"
"lateral projections may show a vertical opaque line (pericardial fluid) separating a vertical lucent line directly behind the sternum (pericardial fat) anteriorly from a similar lucent vertical lucent line (epicardial fat) posteriorly; this is known as the Oreo cookie sign 5"
"Differentiation from an epicardial fat pad and a left pleural effusion, which have similar sonographic appearances, relies on the recognition of the anatomical boundaries of the fluid collection in question; pleural effusions are bounded anteriorly by the descending aorta, and a fat pad will be seen most prominently in the atrioventricular groove. Additionally, epicardial fat pads have a different echotexture, with low-level echoes scattered throughout 8."
"If small, asymptomatic and clinically not suspected, then conservative management is usually favoured 13."