Echo - Aortic Stenosis Flashcards
Stages of Aortic Stenosis
A - At risk for disease
B- Progressive disease
C - asymptomatic Disease
c1 - normal LVEF
c2 - LVEF <50%
D- symptomatic Severe disease
D1 - high gradient
D2 - low flow, low gradient with reduced LVEF
D3 - low gradient with normal LVEF or paradoxical low flow
Can cause aortic stenosis
- 1-2% og general population
fusion of two cusps
associated with aortopathy
common in Male
BAV - most common is fusion of RCC and LCC
fatal AS in children under 1 year old, rare in adults with uni- or acommisural
usually in the absence of severe calcification of valves
unicuspid aortic valve
usually in the absence of severe calcification of valves
At risk to develop As
see pic
Classification of BAV fused on fusion of cusps
see pic
associated aortopathy of BAV?
- Dilatation of Sinus of valsalva
- aorta dilatation
- aortic coarctation
Clues for coarctation of aorta in BAV
- associated with hypertension
- on CWD at descending aorta (suprasternal view), look for saw like pattern - persistently high velocity both in systole and diastole
characteristics of a Quadricuspid Aortic Valve
see pic
the most common cause of AS
Calcific Degenerative AS
Grading severity of Aortic Stenosis
MILD
- AVA of >1.5 cm2,
-mean G <20mmHg,
- Vmax <3/sec
Moderate
- AVA of >1-1.5 cm2,
mean G of 20-39 mmHg,
Vmax of 3-3.9/sec
SEVERE
- AVA of <1.0 cm2 OR AVAi ≤0.6
mean G ≥40mmHg,
Vmax ≥ 4/sec
***VERY SEVERE
mean G of ≥ 60mmHg,
Vmax ≥5/sec
Criteria for a D2 - symptomatic severe low flow, low gradient AS with reduced LVEF
- AVA of <1.0 cm2
- with resting mean G <40mmHg,
-resting Vmax ≥ 4/sec - LVEF <50%
***DSE shows AVA of <1.0 cm2 with Vmax ≥ 4/sec at any flow rate
Criteria for a D3 - symptomatic severe low flow AS with normal LVEF or paradoxical low flow severe AS
- AVA of <1.0 cm2
- with resting mean G <40mmHg,
-resting Vmax ≥ 4/sec - Stroke volume index of <35mL/m2
*** measured when patient is normotensive (SBP <140mmHg)
Doppler Assessment of Aortic Stenosis
- Stroke volume - LVOT and LVOT VTI
- AVA - Continuity equation
- Vmax across the AV
- mean PG
MEASUREMENT REQUIRED
LVOT diameter via 2D
LVOT VTI via PWD
Peak AV VTI via CWD
Formula for AVA by continuity equation
see pic
severity cut off for velocity ratio for AS?
0.25 for severe AS
>0.5 is normal
Dimensionless index for AS severity
Why planimetry is unreliable in measuring AVA?
(1) the inability to determine whether the plane of imaging is at the leaflet tips where maximum stenosis occurs and is parallel to the orifice; and
(2) planimetry is difficult because of poor cusp definition from heavy calcium deposition, acoustic shadowing, and reverberation artifact.
cut off AVA index for severe AS?
≤0.6 cm2/m2
Discordant between AVA and MG in AS. what will you check??
see pic
for low gradient AS with LVEF <50%, do DSE
Dobutamine stress echo interpretation for true and pseudo severe AS.
True-severe AS is generally defined by an AVA of 1.0 cm2 or less and a MG of 40 mm Hg or greater at any
stage during DSE.
Typically, pseudo-severe AS shows a marked increase in AVA and little or no increase in gradients in response to increasing flow
whereas true-severe AS shows little or no increase in AVA and a marked increase in gradients which is congruent with the relative increase in flow
Goal of DSE for AS
increase SV by 20%
for true severe AS - AVA ≤1.0 cm2 and MG ≥40mmHg
pseudo severe AS. - AVA >1cm2 and MG ≤40mmHG
What are the echo parameters that is important in classifying severe AS?
flow (SVi), mean gradient and LVEF
type of AS that is usually caused by discrete fibrous membrane and by muscular narrowing
subvalvular AS
differential dx for Dynamic LVOT obstruction
a type of subvalvular AS
type of AS that can be focal or diffuse narrowing starting at the sinotubular junction
supravalvular AS
*** associated with Williams-Beuren Syndrome
Williams syndrome, also known as Williams-Beuren syndrome, is a rare, neurodevelopmental, genetic condition characterized by many symptoms including unique physical features, delayed development, cognitive challenges and cardiovascular abnormalities.
When to use CT calcium score in patient with AS?
low flow, low gradient AS with LVEF <50% AND
- DSE is not feasible or inconclusive, or
- mean flow rate at rest echo >200 mL/sec
-> proceed with AV calcium scoring by MDCT
cut off: ≥1,200 for female, ≥2000 for male
in AS, anatomical and procedural factors favours TAVI over SAVR?
- TAVI feasible via transfemoral approach
- Sequelae of chest radiation
- Porcelain aorta
- High likelihood of severe patient-prosthetic mismatch (AVAi <0.65cm2/m2 BSA)
- severe chest deformation or scoliosis
ESC guidelines on Valvular Heart Disease
in AS, clinical characteristics that favous TAVI over SAVR?
- Higher surgical risk
- Older age
- Previous Cardiac Surgery (particularly intact CABG at risk of injury during repeat sternotomy.
- Severe Frailty (>2 factors of Katz Index)
***active or suspected IE favours SAVR
in severe AS, SAVR vs TAVI?
see pic
in SYMPTOMATIC SEVERE AS, which are class I indication for intervention. (ESC)
- severe, high gradient AS
mean G ≥ 40mmHg
Vmax ≥ 4m/sec
AND AVA ≤ 1cm2 or AVAi ≤0.6cm2/m2 - severe, low flow (SVi ≤35ml/m2), low gradient (< 40mmhg) AS with LVEF <50%), and evidence of flow (contractile) reserve
***flow reserve is assess after DSE. there should be ≥20% increase in SV
in ASYMPTOMATIC SEVERE AS, which are class I
indication for intervention. (ESC)
- severe AS with LVEF <50% without another cause
- severe AS and demonstrable symptoms on exercise testing
in SYMPTOMATIC SEVERE AS, which are class IIa
indication for intervention. (ESC)
- severe, low flow, low gradient AS with normal LVEF
-severe, low flow (SVi ≤35ml/m2), low gradient (< 40mmhg) AS with LVEF <50%), AND no evidence of flow (contractile) reserve, particularly when CTT calcium score confirms severe AS
***flow reserve is assess after DSE. there should be ≥20% increase in SV
in ASYMPTOMATIC SEVERE AS, which are class IIa
indication for intervention. (ESC)
-severe AS with LVEF <55% without another cause
- severe As with sustained fall on BP (>20mhg) during exercise testing
- severe AS, LVEF >55%, low risk procedure AND
present of one of the following:
1. vere severe AS (mean G ≥ 60mmhg, Vmax of >5m/s)
2. severe valve calcification (ideally assessed by CCT) and Vmax progression of ≥0.3 m/s/yr
4. markedly elevated BNP levels (x 3 x age- and sex- corrected normal range) without any other explanation
TAVI vs SAVR?
SAVR, class I indication for:
- <75 yrs old and STS-PROM/EuroSCORE II <4%, or
- patients who are operable and unsuitable for transfemoral TAVI
TAVI, class I indication for
- ≥ 75yrs old, or
- STS-PROM/EuroSCORE of >8%, or
- unsuitable for surgery
For Moderate AsS patient undergoing CABG or procedure on the ascending AORTA or another valve , what is the recommendation?
- Class IIa for SAVR
