Klein TTE Q book Flashcards
How can you differentiate linear aortic artifacts (which are caused by reverberation) from aortic dissection?
1) These artifacts typically occur when the aortic diameter is > than the LA diameter
2) Dissection flaps, unlike linear artifacts, have independent motion the posterior aortic wall (artifacts move in parallel to the posterior aortic wall)
3) Dissection flaps, unlike artifacts, have rapid oscillatory movements
4) Artifacts are usually created at the posterior aortic wall interace with the LA, not the anterior aortic wall
What type of artifact does a mechanical valve create?
Reverberation artifact
What type of artifact is a double image aortic valve?
Refraction
What type of artifact is a mitral valve below diaphragm?
Mirror image
What type of artifact is distortion of ball and cage valve?
Propagation speed
How can you tell the difference between a side lobe artifact and a refraction artifact, when both appear adjacent to the original structures?
- Echo Intensity:
Side Lobe Artifact:
The artifact is usually fainter and less well-defined compared to the actual structure since it originates from secondary energy (side lobes).
Refraction Artifact:
The artifact can appear nearly as bright and well-defined as the actual structure because it is part of the primary beam, albeit redirected.
- Behavior with Probe Manipulation:
Side Lobe Artifact:
Does not move significantly with changes in probe angle or position.
Persistently aligns with the original reflective structure producing the side lobe.
Refraction Artifact:
Shifts position depending on the angle of insonation because refraction follows Snell’s Law.
Moving the probe can make the artifact disappear or change its displacement.
When does a mirror image artifact occurs, and how can you reduce it?
It occurs when the doppler gains are set too high and it can be reduced by decreasing the power output or gain and optimising the angle between the ultrasound beam and doppler flow.
How can you differentiate from a LV thrombus and near field clutter?
1) Change from fundamental to harmonic imaging (this also helps with reduce side lobe / grating lobes / reverberation artifacts)
2) Increasing transducer frequency
3) Decreasing the depth
4) Using multiple views
5) Contrast agents (decrease the MI)
What are the artifacts that could mimic LV thrombus?
1) Reverberation (near-field clutter, comet tail)
2) Range ambiguity
3) Attenuation (shadowing)
What is a ghosting artifact
Colour doppler that is distorted beyond anatomic borders due to multiple reflections
What is refraction?
Bending of the ultrasound beam that results in side-to-side images
How can you tell AR on a M-mode tracing of the LV?
Fluttering of the mitral valve leaflets
What, on an M-mode of the LV, suggest high LVEDP?
The “b-bump” which is at the end of the leaflet
What is the formula for relative wall thickness?
(2 x PWTd)/LVIDd
The UL is 0.42
What is the UL for LV mass index
115 g/m2 in men
95 g/m2 in women
Do you need to have a holodiastolic murmur for severe AR?
In acute severe AR, the LV diastolic pressure rises rapidly because the LV is non-compliant (stiff). This can cause early equalization of aortic and LV pressures, truncating the murmur (it may only be early diastolic).
Similarly, in chronic severe AR with very low systemic vascular resistance or hypotension, the aortic diastolic pressure may fall, reducing the pressure gradient and shortening the murmur.
If you put a pulse wave in the RVOT just prior to the pulmonary valve in a patient in NSR with severe PAH, what will you see?
Small or absent A wave (atria cannot contract sufficiently against the high RVEDP seen, therefore v little blood flow so small or absent A wave)
A mid-systolic notch (flying “W” sign)
In an acute PE, are pulmonary pressures significantly raised?
typically not >50 mmHg
What findings do you see on M mode for a subaortic membrane?
Fluttering of the RCC (top) cusp
Abrupt, very early posterior motion of the right cusp of the aortic valve
Talk about chamber collapse assessment in tamponade assessment:
Normal Chamber Dynamics:
The RV and RA naturally collapse during parts of the cardiac cycle due to physiologic variations in pressures.
RA collapse: Occurs briefly during atrial systole (end-diastole).
RV collapse: May occur during early systole due to contraction.
Pathologic Chamber Collapse in Tamponade:
In tamponade, pericardial pressure exceeds the chamber pressures (RA and RV diastolic pressures), leading to prolonged, abnormal chamber collapse.
RA collapse: Abnormal if it persists for more than one-third of the cardiac cycle.
RV collapse: Significant if it occurs during diastole, when the RV is supposed to be filling.
RA collapse in tamponade occurs in late diastole, when the RA should be filling.
RV collapse in tamponade occurs in early diastole, when the RV is supposed to be filling.
Is hypertension related to dilatation of the sinuses of Valsalva?
No - just the distal aortic segments
When should the aortic annulus be measured?
Mid-systole
When should all the other aortic measurements be made e.g. STJ, Asc aorta
End-diastole
An IVC diameter <1cm with spontaneous collapse indicates
intravascular volume depletion