Case Resolution

Murmur

A 62 y/o with hx of iron deficiency anemia and hip pain was hospitalized for aspiration pneumonia and MSSA bacteremia. A murmur was heard on physical examination.

Image Interpretation

This clips shows an apical 4 chamber view of the heart. Color Doppler is being used to assess the tricuspid valve.

Proper use of color Doppler of a valve to assess for regurgitation should put the top of the box just past the valve leaflets (in the RV here) and include chamber which the regurgitant jet is being assessed (the RA here).

Mild TR is demonstrated as a narrow "blue" jet travelling to the bottom of the screen. Remember, flow away from the probe appears blue (it is getting "colder"!).

Sound Reasoning

A still image is shown below of the clip. The arrow points the tricuspid regurgitation jet. The TR was classified as "mild" on formal TTE. Mild TR is found in up to 70% of people, and thus is a normal finding. In fact, the interesting part about TR is that it is critical in the evaluation of PA pressures by echo. The velocity of the TR jet is a key component of the measurement and factors into Bernoulli Principle to measure pressure on the right side of the heart. Thus if no TR, you cannot measure the PA pressure by echo!

Two other quick learning principles.

If you are in the apical 4 chamber view, two key features distinguish the RV from the LV

• the RV contains the moderator band, labelled "MB" on the annotated image below
• the RV "inserts" into the LV at the apex, thus the LV extends further to the apex (and closer to the probe) in the A4C view (outlined in red)

Lastly, this patient did not have a vegetation, by POCUS, TTE, or TEE. Remember, TTE has low sensitivity for vegetations, thus by extension, POCUS should be used for "rule in" only of endocarditis.