Definition:

Cardiac tamponade is a life-threathening condition in which a pericardial effusion has developed so rapidly or accumulated so much that it compresses the heart (like squeezing an orange in your hands).  Consequently, the heart cannot pump or flow blood properly because it cannot fill properly.  Like all other pericardial diseases, it is caused by: infection, drugs, trauma, surgery, connective tissue disorders, radiation therapy, uremia, pericarditis, and pneumopericardium.  

Symptoms:

• Dyspnea (shortness of breath)
• Tachypnea (high respiratory rate)
• Tachycardia (high heart rate)
• Neck vein distension
• Hypotension (low blood pressure)

Diagnosis:

• Distant heart sounds with stethoscope
• Ewart sign (area of dullness with bronchial breath sounds over left scapula)
• Pulsus paradoxus (decrease in systolic blood pressure >10mmHg with inspiration)
• Chest X-Ray - enlarged heart
• Echocardiography - presence of pericardial effusion
• Cardiac catheterization - left/right atrial pressures are equal

Treatment:

• Oxygen
• Volume expansion with IV fluids
• Bed rest with leg elevation
• Inotropic drugs (dobutamine)
• Positive-pressure mechanical ventilation
• Pericardiocentesis
• Emergency subxiphoid percutaneous drainage
• Surgery
  • Surgical creation of pericardial window - to allow drainage of effusion
  • Pericardio-peritoneal shunt - patients with cancer causing effusion
  • Pericardiectomy - last resort