<unk>  is a condition that affects the cardiovascular system. It typically begins with blood accumulating in the pericardial sac posterior to the heart, and eventually expands to surround the entire heart. The fluid build-up then causes pressure within the pericardial sac to increase. If the pressure becomes greater than the intracardiac pressure of the heart, compression of the adjacent cardiac chambers can occur. This compression, called cardiac tamponade, is often associated with<unk>  and can be fatal if not diagnosed and treated promptly. Early signs of this compression include right atrial inversion during ventricular systole followed by diastolic compression of the right ventricular outflow tract. There have also been cases reported in which<unk>  was noted as an initial manifestation of essential thrombocythemia.
Hemopericardium
Pneumopericardium
Urinothorax
Chylothorax
Hemothorax
Pneumomediastinum
Fibrothorax
Pulmonary hematoma