From the Guidelines
Pericardial effusion is characterized by the accumulation of excess fluid in the pericardial sac, which can lead to cardiac tamponade, a life-threatening condition.
Key Features of Pericardial Effusion
- Size: Pericardial effusion can be classified as small (<10 mm), moderate (10-20 mm), or large (>20 mm) based on the end-diastolic distance of the echo-free space between the epicardium and parietal pericardium 1.
- Symptoms: Classic symptoms include dyspnoea on exertion, orthopnoea, chest pain, and/or fullness 1.
- Causes: Common causes of pericardial effusion include cancer, infections, iatrogenic causes, and connective tissue diseases 1.
- Diagnosis: Transthoracic echocardiography is the first-line imaging test for diagnosing pericardial effusion and assessing its hemodynamic significance 1.
- Classification: Pericardial effusion can be classified according to its onset, distribution, hemodynamic impact, composition, and size 1.
Important Considerations
- The haemodynamic tolerance of pericardial effusion is more related to the rapidity of appearance of the effusion than to its total volume 1.
- Loculated pericardial effusions or pericardial effusions that contain clots may be difficult to diagnose using a transthoracic approach and may require transoesophageal echocardiography 1.
- Effusive-constrictive pericarditis is a rare condition where pericardial effusion is present in combination with constrictive pericarditis, and its diagnosis often becomes apparent during pericardiocentesis 1.
From the Research
Features of Pericardial Effusion
The features of pericardial effusion can be summarized as follows:
- Pericardial effusion is defined by an increase in the physiological amount of fluid within the pericardial space 2
- It can appear following different medical conditions, mainly related to inflammation and cardiac surgery 2
- The size of the effusion, its hemodynamic importance, and possible associated diseases should be assessed when a pericardial effusion is detected 3
- The causes of pericardial effusions include infections, cancer, connective tissue diseases, pericardial injury syndromes, metabolic causes, and myopericardial and aortic diseases 3
- Echocardiographic evaluation is paramount for timely and appropriate diagnosis and management of pericardial effusion 2
Echocardiographic Findings
Echocardiographic findings that suggest a pericardial effusion is causing tamponade include:
- Diastolic right ventricular collapse (high specificity) 4
- Systolic right atrial collapse (earliest sign) 4
- A plethoric inferior vena cava with minimal respiratory variation (high sensitivity) 4
- Exaggerated respiratory cycle changes in mitral and tricuspid valve in-flow velocities as a surrogate for pulsus paradoxus 4
- A structured echocardiographic approach including two-dimensional, M-mode, and Doppler echocardiographic evaluation assessing the quantity and quality of pericardial fluid, collapse of cardiac chambers, respiratory variation of the ventricular diameters, inferior vena cava collapsibility, and flow patterns in atrioventricular valves 2
Clinical Manifestations
Pericardial effusion can have a variety of clinical manifestations, ranging from:
- Asymptomatic, incidentally uncovered small effusions 5
- Life-threatening cardiac tamponade 2, 3, 6
- The management of patients with pericardial effusions is mainly based on four parameters: haemodynamic impact on diastolic function, elevation of inflammatory markers, presence of a specific underlying condition, and size and duration of the effusion 5