Measuring pericardial thickness on echocardiography involves visualizing the pericardial layers and using the echo machine's measurement tools.
On a two-dimensional (2D) echocardiogram, the layers of the pericardium are seen as thin, bright lines surrounding the heart muscle (myocardium). You measure the thickness by identifying these lines in appropriate views and using the electronic calipers on the echocardiography machine.
Visualizing the Pericardium on Echo
When performing transthoracic echocardiography (TTE), the sonographer or physician maneuvers the ultrasound probe to obtain views that clearly show the heart and its surrounding structures, including the pericardium.
According to the reference:
- When visualized on two-dimensional echocardiography, the layers of the pericardium appear as thin echogenic lines surrounding the myocardium.
This means the pericardium shows up as brighter lines compared to the heart muscle on the echo screen.
Measurement Process
While the reference doesn't detail the step-by-step caliper placement, the general process for measuring structures on 2D echo involves:
- Obtaining a clear image where the structure (in this case, the pericardium) is well-visualized.
- Freezing the image at an optimal point in the cardiac cycle, often in diastole when the heart is relaxed and the pericardium might be most uniformly tense.
- Using the measurement tools (calipers) available on the echocardiography machine.
- Placing the first caliper at the outer edge of the pericardial layer.
- Placing the second caliper at the inner edge of the visualized pericardial layer, measuring the distance perpendicular to the layer.
The measurement should ideally be taken in multiple views where the pericardium is clearly seen, such as the parasternal long-axis or apical views, to ensure accuracy.
Normal Pericardial Thickness
Understanding the normal range is crucial for interpreting the measurement.
Based on the provided information:
- The normal thickness of the visualized pericardial layers on TTE is less than 3 mm.
Therefore, a measurement significantly greater than 3 mm could indicate increased pericardial thickness, potentially due to conditions like pericarditis (inflammation) or other infiltrative processes.
Summary of Key Points
Here's a quick look at the essential aspects:
- Appearance on Echo: Thin, bright (echogenic) lines around the heart muscle.
- Measurement Tool: Electronic calipers on the echocardiography machine.
- Method: Measure the distance across the visualized pericardial layers in a clear 2D image.
- Normal Range: Less than 3 mm.
Measuring pericardial thickness is a part of a complete echocardiographic examination when assessing for potential pericardial disease.
