Ultrasound Case #13 – Just Relax
A 64 year old female presents to your ED with 1 week of worsening shortness of breath. A chest xray is done and shows pulmonary edema vs atypical pneumonia. You consider CHF but note that her ejection fraction appears normal and wonder if she may have heart failure with preserved ejection fraction (HFpEF).
Based on the following ultrasound images and clips, what is the primary cause of this patient’s heart failure?
The patient’s diastolic function appears normal.
We have discussed the mitral valve inflow pattern in a previous post, but here again briefly. As the LV relaxes it creates a negative force that pulls blood from the atria into the ventricle. In the 2nd image, with the PW doppler over the mitral valve leaflets, this passive filling is the first wave you see and called the E wave. The next wave is the A wave and that corresponds to the atrial kick. Under normal circumstances the E>A wave. As the LV becomes stiff and fails to relax properly, the A>E, this is early diastolic failure or impaired relaxation.
As diastolic failure progresses, the MV inflow patter becomes “pseudonormal.” The next (3rd) image above is a diastology cheat sheet from @gasmanjonny that helps explain this concept. As the LA pressure continues to increase due to longstanding diastolic dysfunction, once again the E>A wave due to high LA pressures causing greater early LV filling.
So to differentiate between normal and “pseudonormal” you need tissue doppler (TD). TD is another mode on the ultrasound that specifically looks at the movement of tissues and can detect much lower velocities. The TD gate goes on the medial mitral valve annulus. Here in the 4th image you notice 2 negative deflections. These deflections once again represent LV relaxation and atrial kick and are called e’ and a’ respectively. As you can see our patient shows the normal pattern where e’>a’ and therefore has normal relaxation.
This can be more complicated and I have include a flow sheet from UpToDate showing a more complete evaluation, but from an acute care perspective, if you are worried about diastolic failure, a normal E/A and e’/a’ pattern should reassure you.
E/A = 1.61
E/e’ = 5.6
Septal e’ velocity = 13.88
