The CXR shows globular enlargement of the cardiac shadow, sometimes known as the "water bottle sign". This is due to a pericardial effusion. The lungs and pleural spaces are clear. A coronal view on CT confirms a large pericardial effusion:
Causes of a pericardial effusion include:
- Inflammation: following a myocardial infarction, known as Dresslers syndrome, or in rheumatological disorders.
- Infections: viruses, atypical pathogens such as mycobacterium tuberculosis
- Idiopathic: no known cause