accumulation of pericardial fluid under pressure results in impaired cardiac venous filling and resultant impaired cardiac output which may rapidly become life threatening unless relieved by therapeutic pericardiocentesis
clinical features
can be suspected based on:
history and physical examination
near-syncope or syncope
hypotension
tachycardia
elevated JVP
pulsus paradoxus
peripheral oedema if subacute or chronic aetiology
NB. must be differentiated from other conditions such as: