Penetrating chest trauma.
Hypotension and tachycardia.
This is a subcostal view.
There is a 2.5cm echogenic mass within the pericardium compressing the right ventricle.
In the setting of penetrating cardiac trauma this represents acute haemopericardium and clot formation within the pericardium. Subsequent compression of the right sided chambers is reducing filling and causing obstructive shock.
Traditional teaching is that a pericardial effusion will appear as an echo free rim within the pericardial space.
This is not always the case, and particularly with acute haemopericardium blood can clot and this appears moderately echogenic.