From the Guidelines
Pericardial effusion on transthoracic echocardiography (TTE) is associated with a swinging motion of the heart within the pericardial sac, often described as "swinging heart" or pendular motion, which can progress to signs of cardiac tamponade, including electrical alternans, right ventricular diastolic collapse, and right atrial collapse. This characteristic finding occurs when a significant amount of fluid accumulates in the pericardial space, allowing the heart to move more freely within the fluid-filled pericardial sac 1. The swinging motion is particularly important to recognize as it may indicate a hemodynamically significant effusion that could progress to tamponade, requiring urgent intervention such as pericardiocentesis 1. Some key echocardiographic parameters to evaluate in the context of pericardial effusion include chamber collapse, Doppler inflow variations, and the size and dilation of the inferior vena cava (IVC) 1. In more severe cases, the swinging motion can be accompanied by signs such as early diastolic collapse of the right ventricle, late diastolic collapse of the right atrium, abnormal ventricular septal motion, and exaggerated respiratory variability in mitral inflow velocity 1. The degree of swinging motion generally correlates with the size of the effusion and the rapidity of fluid accumulation, making it a critical finding to recognize in the assessment of pericardial effusion on TTE 1. It is essential to integrate these echocardiographic findings with the clinical context to guide further management, including the potential need for pericardiocentesis or other interventions 1. Overall, the identification of swinging heart motion on TTE is a crucial aspect of diagnosing and managing pericardial effusion, particularly in cases where cardiac tamponade is suspected or confirmed 1.
From the Research
Ventricular Motion Associated with Pericardial Effusion
The type of ventricular motion associated with pericardial effusion seen on transthoracic echocardiography (TTE) includes:
- Early diastolic collapse of the right ventricle 2
- Late diastolic collapse of the right atrium 2
- Respiratory variation in mitral valve inflow, akin to pulsus paradoxus 2
- Decreased early filling (E wave) of mitral valve inflow, related to loss of the y descent 2
Echocardiographic Features
Echocardiographic examination is crucial in confirming the size, location, and other characteristics of the causal pericardial collection, and several features support the hemodynamic diagnosis of tamponade, including:
- Equalization of diastolic pressures across all chambers 2
- Pulsus paradoxus and loss of the normal "y" descent of a jugular venous pressure waveform 2
- Confirmation of the size and location of the pericardial effusion 3, 2, 4, 5, 6
Clinical Significance
Pericardial effusion can lead to cardiac tamponade, a medical emergency that requires prompt recognition and treatment, and the prognosis of pericardial effusions largely depends on the underlying etiologies 3, 4, 5, 6