Echocardiography Chapter 7: Diastology Flashcards
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How is cardiac index calculated?
CI = CO/BSA
What finding is consistent with moderate RV dilation?
a) RV size < LV size
b) RV size = LV size
c) RV size > LV size
b) RV size = LV size
What finding in PSAX is consistent with RV pressure overload?
Hint: distortion of a certain structure, and the stage of the cardiac cycle it occurs in
IVS flattening in systole
What finding in PSAX is consistent with RV volume overload?
Hint: distortion of a certain structure, and the stage of the cardiac cycle it occurs in
IVS flattening in diastole
What is the mechanism by which early filling velocity decreases in Stage 2 diastolic dysfunction (aka, why the small E-wave)?
As diastolic dysfunction progresses, LV loses compliance, and can’t expand as well. When blood enters a smaller chamber, that causes an increase in LVP, and the flow through the MV will be impeded, lowering early filling velocities.
What are some indications of Stage 2 diastolic dysfunction (~6 answers)?
- decreased e’, d/t loss of elasticity
- decreased IVRT, d/t premature MV opening as a result of increased LAP
- decreased S-wave velocity in pulmonary veins, as blood struggles to enter LA against pressure gradient
- increased RVSP, d/t backpressure from pulmonary veins causing RV to have increased afterload
- increased D-wave velocity, as the opening of the MV “vents” the pressure buildup in the LA, which results in more forceful flow through the pulmonary veins
- LA dilation
Why is dT decreased in Grade 3 diastolic dysfunction?
With impaired LV compliance, LV pressure doesn’t take as long as it should to match LAP as filling outpaces expansion of LV chamber.
If it’s unclear whether diastolic dysfunction is present, what four factors do we look at, and consider diastolic dysfunction if more than two are abnormal?
- mean E/e’ > 14? (means filling outpaces expansion)
- LA volume > 34 mL/m2?
- e’ of septal MV leaflet < 7 cm/s or e’ of lateral MV leaflet < 10 cm/s? (means slow myocardial relaxation)
- TRVmax > 2.8 m/s (means high RVSP d/t backpressure caused by high LAP)?