Artifacts and Mimics
Echocardiographic artifacts are apparent findings that do not represent true anatomy or pathology. Suspect artifact when a finding appears in only one view, crosses anatomic boundaries, or changes substantially with transducer position or machine settings.
A true abnormality should generally be reproducible in multiple planes.
Evaluation¶
When an unexpected finding appears:
- Image it from another window.
- Sweep through it in multiple planes.
- Adjust gain, depth, focus, frequency, and harmonics.
- Apply color or spectral Doppler when appropriate.
- Use an ultrasound-enhancing agent if endocardial definition is inadequate.
- Consider TEE, CT, or CMR if uncertainty would change management.
Common Artifacts¶
| Artifact | Appearance | Common pitfall |
|---|---|---|
| Reverberation | Parallel, equally spaced echoes | Dissection flap or intracardiac mass |
| Mirror image | Duplicated structure beyond a strong reflector | Additional chamber, vessel, or mass |
| Side-lobe artifact | False echoes adjacent to a strong reflector | Thrombus or vegetation |
| Acoustic shadowing | Signal loss behind calcification or prosthetic material | Missed regurgitation or vegetation |
| Near-field clutter | Spurious echoes close to the transducer | LV apical thrombus |
| Dropout | Apparent interruption of a thin structure | ASD, VSD, leaflet perforation, or dissection |
| Color blooming | Color extending outside true flow boundaries | Exaggerated regurgitation or shunt |
| Spectral mirroring | Similar Doppler signal on both sides of baseline | False bidirectional flow |
Reverberation¶
Reverberation results from repeated reflections between strong interfaces. Common sources include prosthetic valves, calcification, leads, catheters, and the pericardium.
A reverberation line in the ascending aorta may mimic a dissection flap. Artifact often extends beyond the vessel or moves identically with another reflector.
Acoustic Shadowing¶
Calcification, prosthetic valves, ribs, and surgical material may obscure structures located behind them.
Use alternative windows or TEE when shadowing limits assessment for prosthetic regurgitation, vegetation, or paravalvular complications.
Near-Field Clutter¶
Near-field artifact is particularly important when evaluating the LV apex. It may create or conceal an apparent thrombus.
A true thrombus should:
- Persist in multiple views
- Remain distinct from the endocardium
- Occupy an area of abnormal wall motion or blood stasis
- Produce a reproducible filling defect with contrast
Dropout¶
Thin structures aligned parallel to the ultrasound beam may disappear and create a false defect.
Confirm a suspected ASD, VSD, leaflet perforation, or dissection using additional planes and Doppler. Color flow should also be interpreted cautiously because excessive gain can produce blooming.
Common Anatomic Mimics¶
| Structure | Potential mimic |
|---|---|
| Coumadin ridge | LA or LAA mass |
| Crista terminalis | RA mass |
| Eustachian valve | RA vegetation or thrombus |
| Chiari network | Mobile RA thrombus |
| Moderator band | RV mass |
| RV trabeculations | RV thrombus |
| Papillary muscle or false tendon | LV mass |
| Lipomatous hypertrophy of the septum | Atrial mass |
| Lambl excrescence | Valve vegetation |
| Epicardial fat | Pericardial effusion or mass |
Normal variants are identified by their characteristic location, attachment, texture, and motion.
Suggested Reporting¶
A linear echodensity is intermittently visualized in the left atrium but is not reproduced in orthogonal views and is favored to represent artifact.
The LV apex is incompletely visualized because of near-field artifact. Apical thrombus cannot be excluded. Repeat imaging with an ultrasound-enhancing agent is recommended if clinically indicated.
A prominent crista terminalis is present in the right atrium, representing a normal anatomic variant.
Acoustic shadowing from the mitral prosthesis limits assessment for posterior paravalvular regurgitation.
A mobile echodensity is reproducibly visualized in multiple planes and cannot be confidently classified. Additional evaluation with TEE is recommended.
Key Points¶
- Confirm unexpected findings in multiple planes.
- Change the window and machine settings before diagnosing pathology.
- Dropout may create a false defect; blooming may exaggerate flow.
- Near-field clutter is a major pitfall when assessing the LV apex.
- Report uncertainty and recommend additional imaging when it would change management.