Echocardiography Chapter 7: Diastology

Question 1

equation

How is cardiac index calculated?

Answer 1

CI = CO/BSA

Question 2

What finding is consistent with moderate RV dilation?

a) RV size < LV size

b) RV size = LV size

c) RV size > LV size

Answer 2

b) RV size = LV size

Question 3

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

Answer 3

IVS flattening in systole

Question 4

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

Answer 4

IVS flattening in diastole

Question 6

What is the mechanism by which early filling velocity decreases in Stage 2 diastolic dysfunction (aka, why the small E-wave)?

Answer 6

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.

Question 7

What are some indications of Stage 2 diastolic dysfunction (~6 answers)?

Answer 7

• 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

Question 8

Why is dT decreased in Grade 3 diastolic dysfunction?

Answer 8

With impaired LV compliance, LV pressure doesn’t take as long as it should to match LAP as filling outpaces expansion of LV chamber.

Question 9

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?

Answer 9

1. mean E/e’ > 14? (means filling outpaces expansion)
2. LA volume > 34 mL/m2?
3. e’ of septal MV leaflet < 7 cm/s or e’ of lateral MV leaflet < 10 cm/s? (means slow myocardial relaxation)
4. TRVmax > 2.8 m/s (means high RVSP d/t backpressure caused by high LAP)?