Valvular Aortic Stenosis

Question 1

definition

Answer 1

an obstruction a the valve level involving imperfect cusp development with leaflet thickening and/or fusion

Question 2

Prevalence

Answer 2

3 to 4:1 more common in males than females; infants tend to be full term large babies

Question 3

Pathology/physiology

Answer 3

• valve may be bicuspid or have rudimentary central commissure or raphe in a large anterior cusp With fusion. Cusps may be fused equally or unequally

-Calcification of cusps develops slowly in and after the third decade of life in patients with either mild stenosis or bicuspid Aov. Thus, the adult patient presents with calcific aortic stenosis in what had once been a non obstructive or trivial stenosis of the valve in childhood. The speed with which calcification occurs depends on (1) severity of initial obstruction, (2) infection of the valve, (3) athletic activities, (4) sex- males, and (5) calcium metabolism. Calcification of the aortic valve is not seen in the pediatric population.

Question 4

Echo

Answer 4

Evaluation of valve leaflets should include:

1. number of leaflets and mobility. Doming can be visualized, but leaflets may appear thin (not as echo dense as a calcified valve)

2.Aortic annular ring - ring size may create obstructions (poses difficult courses of treatment). Associated with hypo plastic lt heart syndrome, coarctation of the aorta. Annulus diameter may limit balloon valvotomy/surgery

3.Dysplastic leaflets - no commissural fusion, leaflets appear lumpy, thick, malformed

Question 5

Views

Answer 5

Parasternal/subcostal short axis of aortic valve

Question 6

Mmode/2D

Answer 6

• systolic doming of Aov leaflets
• diastolic doming (prolapse) of Aov leaftlets

-thickened AoV leaflets with decreased excursion

-dysplastic AoV annulus

-LVH

• Poststenotic dilation of the ascending aorta

-Endocardial fibroelastonsis (secondary)

-measure the aortic annulus

• determine the location of the coronary arteries
• determine left ventricular dimensions, thickness and systolic function

-determine the presence of associated defects (coarctation, PDA, MS, PFO, ASD, ebsteins anomaly, tricusipd atresia)

Question 7

PW/CW/color doppler

Answer 7

• turbulence from all views can be seen at the level of obstruction. A complete PW doppler interrogation of the LVOT to the aortic arch should be performed to localize levels of obstruction (apical view)
• Suprasternal notch, high right parasternal, and apical views are the best locations for quantitating the severity of stenosis. Ideally, obtain recordings from all three areas to obtain the most accurate gradient.

-Determine peak velocity
- peak pressure gradient
- mean pressure gradient
- AV area
- velocity ratio
- stroke volume
- cardiac output
- cardiac index
-severity of coexisting regurgitation/lesions