- Clinical science
Pericardial effusion is the acute or chronic accumulation of fluid in the pericardial space (between the parietal and the visceral pericardium) and is often associated with a variety of underlying disorders. The fluid can be either bloody (e.g., following aortic dissection) or serous (usually idiopathic). As the pericardium is rather stiff, the capacity of the pericardial space is limited. In chronic effusion, the pericardium can stretch to a certain degree, accommodating slightly more fluid. In the acute setting, however, the added volume quickly exceeds the maximum capacity of the pericardial space. In both cases, the end result is often cardiac tamponade: compression of the heart which can lead to a life-threatening reduction in cardiac output. Pericardial effusion is initially asymptomatic, but cardiac tamponade has a distinct clinical presentation, including hypotension, tachycardia, jugular venous congestion, and pulsus paradoxus. Echocardiography is the most important diagnostic procedure and usually reveals an anechoic pericardial space. Treatment depends on hemodynamic stability: unstable patients require quick pericardial fluid drainage, through either pericardiocentesis or surgery, whereas in stable patients, treatment focuses on the underlying disease.
Serous pericardial effusion
- Acute pericarditis (especially viral, but also fungal, tuberculous or bacterial)
- Poststernotomy syndrome
- Autoimmune disorders
Limited elasticity of the pericardium → ∼ 150–200 mL of fluid → ↑ pressure in pericardial space → compression of the heart, especially of the right ventricle due to a thinner wall → interventricular septum shifts towards the left ventricle chamber → ↓ ventricular diastolic filling → ↓ stroke volume (+ venous congestion) → ↓ cardiac output
- Usually initially asymptomatic
- Shortness of breath, especially while lying down (orthopnea)
- Beck's triad
- Retrosternal chest pain
- Apical impulse difficult to locate or nonpalpable
- Pallor, cold sweats
- Cardiogenic shock, asystole
- Echocardiography (gold standard)
- CXR: enlarged cardiac silhouette, clear lungs, in severe cases a globular "water bottle-shaped" heart contour (water bottle sign)
- Low voltage
- Electric alternans
- Pericardial fluid drainage: used to sample the effusion in cases of unclear etiology
- Pericardial fluid drainage: ultrasound-guided pericardiocentesis or surgical drainage
- Subsequent surveillance in an intensive care unit (ICU)
- Treatment of underlying cause
Pericardial window: an incision in the pericardium is made that allows continual drainage; from the pericardial space into the pleural cavity to prevent a cardiac tamponade
- Commonly indicated for effusion due to underlying malignancy
- Hemodynamic monitoring
- Consult cardiology immediately.
- Urgent pericardiocentesis
- If HD unstable: without imaging guidance
- If HD stable: US- or CT-guided
- Consult cardiothoracic surgery for surgical drainage if pericardiocentesis is unsuccessful or conditions make it difficult.
- Gentle hemodynamic support
- Serial pulsus paradoxus measurement
- Continuous telemetry, continuous pulse oximetry
- Transfer to ICU/CCU.
- Avoid positive pressure ventilation.