Occurs when the pericardial space fills up with fluid faster than it can stretch, resulting in increased pressure within the pericardial sac 

As fluid accumulates less blood enters the ventricles during diastole as the increasing pressure presses on the heart and forces the septum to bend into the left ventricle, this leads to decreased stroke volume and eventually cardiac arrest if left untreated

Sinus tachycardia, Kussmaul’s sign, pericardial rub, pulsus paradoxus, 

Beck’s Triad - hypotension, raised JVP, muffled heart sounds 

ECG: Low QRS voltage, electrical alternans (beat-to-beat shift in QRS/P waves)

Chest X-Ray: Large globular heart, cardiomegaly seen with >200 ml of blood

Echo: Systolic collapse of right atrium followed by diastolic collapse of right 

Ventricle. Fluid accumulates around the heart which starts posteriorly.

Pericardiocentesis 

Open surgical drainage with pericardiectomy or pericardial window

Cardiac arrest from reduced cardiac output