ECHOCARDIOGRAPHIC EVALUATION OF AORTIC STENOSIS

EVALUATION OF

AORTIC STENOSIS

An Echocardiographic Approach

Dr. NAGULA PRAVEEN2nd yr PG 2/18/2015

Aortic valve

• Aortic valve is composed of three cusps of equal size, each of which

is surrounded by a sinus, separated by a commissure and supported by

a fibrous annulus.

• Cusps are crescent shaped, open fully in systole to allow forward flow

and close in diastole.

• The free edge of cusp curves upward from the commissure and forms

a slight thickening at the tip or midpoint, called the node of Arantius.

• When the valve closes, three nodes meet in the center, three lines of

fusion radiate outward viewed as a Yshape in short axis view.

• Overlap of valve tissue along the lines of closure produces a tight seal

and prevents backflow during diastole.

Normal Aortic valve

Sinus of Valsalva

• Behind each cusp is its assosciated sinus (outpouchings).

• Support cusps during systole and provide a reservoir of blood to

augment coronary artery flow during diastole.

• LCA – arise from left sinus.

• RCA – arise form right sinus.

• Noncoronary cusp is Posterior and Rightward, just above the base

of interatrial spetum.

• At the superior margins of the sinuses, aortic root narrows at the

Sinotubular junction.

Normal aortic valve cusps appear thin and delicate, difficult

to visualize.

Long axis view – cusps appear as linear parallel lines close to

the walls of the aorta(systole).

Basal short axis view –

Three aortic cusps can be visualized within the annulus during

diastole – Y shape or inverted Mercedes Benz sign.

Aortic annulus can be visualized clearly in systole.

Number of cusps, fusion of one or more commissures can be

known.

Acquired valvular aortic stenosis – cusps become thickened,

restricted.

Position during systole is no longer parallel to the aortic walls.

Edges point toward the center of the aorta.

Severe cases – total lack of mobility. identification of cusps may be

impossible.

2D Echo-Long axis view

Diastole Systole

2D Echo-Short axis view

Diastole Systole

Y or inverted Mercedes-Benz sign

2D - Apical five chamber view

2D – Suprasternal view

CLASSIFICATION OF

AORTIC STENOSIS

Aortic stenosis

Congenital

Valvular

Bicuspid aortic valve

Unicuspid

Quadricuspid

Subvalvular

Dynamic

HOCM

Fixed

Membranous Fibromuscular

Acquired

Degenerative Rheumatic

Native valve

disease

Prosthetic valve

PPM

IESupravalvular Type I

TypeII

Type III

Aortic sclerosis

About 25% of all adults over age 65 yrs have aortic valve sclerosis.

Thickened calcified cusps with preserved mobility.

No significant obstruction to LV outflow.

Typically associated with peak doppler velocity of < 2.5 m/sec.

In Cardiovascular Health Study ,for group of patients 65 yrs,the

aortic valve was normal in 70% of cases,sclerotic in 29% and stenotic

in 2%. JACC.1997;29(3):630-4.

In Euro Heart Survey of 4910 pts in 25 countries,AS was the most

frequent lesion,accounting for 43% of patients with VHD.

Eur Heart J.2003;24(13):1231-43.

Calcific Aortic Stenosis

10-15% of aortic sclerosis patients progress to severe AS.

Nodular calcific masses on aortic side of cusps.

No commissural fusion.

Free edges of cusps are not involved.

Stellate- shaped systolic orifice.

Cosmi et al,Arch Int Med 2002;162(20):2345-7.


Plax (Parasternal long axis) view

showing echogenic and immobile

aortic valve.

Marked increase in echogenicity.

Reduced systolic opening.


Parasternal short-axis view

showing calcified aortic valve

leaflets. Immobility of the cusps

results in only a slit like aortic

valve orifice in systole.

Used for valve area

(planimetry).


Calcification of a bicuspid or tricuspid valve, the severity can be graded semi-quantitatively as

0 1+ 2+ 3+ 4+Schaefer BM et al.Heart 2008;94:1634–1638.

The degree of valve calcification is a predictor of clinical outcome.Rosenhek R et al. N Engl J Med 2000;343:611–7.

Imp points.

Directly planimetered aortic valve areas should be interpreted with

caution because of the complex anatomy of the orifice and calcific

shadowing and reverberation, even with 3D imaging.

Direct measurement of valve area on imaging reflects anatomic valve

area, whereas the doppler data provide functional area.

Bicuspid Aortic valve

Bicuspid Aortic Valve (BAV)

Accounts for 2/3rd of cases of severe AS in adults < 70 yrs.

1/3rd of cases in adults > 70 yrs of age.

Severe AS of a BAV is difficult to be differentiated from that of

tricuspid one.

Usual view for differentiation is PARASTERNAL SHORT AXIS

VIEW at the level of great vessels in systole.

PARASTERNAL Long axis view shows systolic bowing of the

leaflets into aorta – “Dome like”.

M MODE – Eccentric closure line (to be taken at the tips of bowed

leaflets).

Two cusps are seen in systole with only two commissures framing an

elliptical systolic orifice (the fish mouth appearance).

Diastolic images may mimic a tricuspid valve when a raphe is

present.



In children, valve may be stenotic

without extensive calcification.

In adults, stenosis typically is due

to calcific changes, which often

obscures the number of cusps,

making determination of bicuspid

vs. tricuspid valve difficult.

Eccentricity index

M mode of BAV

Types of BAV

FUSION OF CUSPS FREQUENCY LEAFLET

CLOSURE LINEREMARKS

RIGHT AND LEFT 70 -80% Anterolateral –

posteromedial closure

line

Larger anterior

leaflet.

RIGHT AND

NONCORONARY

20-30% Anterior –posterior

closure line

Larger

rightward leaflet

LEFT AND

NONCORONARY

1-2% Medial – lateral closure

line

Many bicuspid aortic valves have a raphe in the larger leaflet.

Clear identification of number of leaflets is possible only in systole.

Schaefer et al ,Am J Cardiol 99(5);686-90.2007

Assosciated conditions

Dilated aortic root

Coarctation of aorta

Unicuspid aortic valve

Single eccentric orifice

Prominent systolic doming.

Acommisural

unicommisural

Quadricuspid aortic valve

RAKESH 40Y20150128153142738.avi

RAKESH 40Y20150128153142738.avi

Subvalvular aortic stenosis(1) Thin discrete membrane consisting of endocardial fold and fibrous

tissue.

(2) A fibromuscular ridge

(3) Diffuse tunnel-like narrowing of the LVOT

(4) Accessory or anomalous mitral valve tissue.

Young adults

Valve not stenotic

But high gradients think of subvalvular AS.

TEE – confirmation.

Supravalvular Aortic stenosis

Type I - Thick, fibrous ring above the aortic valve with less

mobility and has the easily identifiable 'hourglass' appearance

of the aorta.

Type II - Thin, discrete fibrous membrane

located above the aortic valve

The membrane usually mobile and may demonstrate doming during

systole.

Type III - Diffuse narrowing

Supravalvular Aortic stenosis

The spatial orientation of the jet and the shape of the CW

doppler velocity curve are similar for fixed obstructions

whether subvalvular,supravalvular,or valvular.

Pulsed doppler,color flow imaging allows localization of the

level of obstruction.

PW – site of increase in flow velocity

COLOR FLOW – Post Stenotic Flow Disturbance.

In patients with both subvalvular and valvular

obstruction,

high pulse repetition frequency doppler ultrasound

will be helpful in defining the maximum velocities

at each site of obstruction.

Rheumatic Aortic StenosisCharacterized by

Commissural fusion

Triangular systolic orifice

Thickening & calcification

Accompanied by rheumatic mitral valve changes.

30% of patients with MS,aortic valve is also affected in

RHD.

Parasternal short axis view showing commissural fusion, leaflet

thickening and calcification, small triangular systolic orifice

Rheumatic aortic stenosis

Differentiation of

Rheumatic vs Calcified AS

RHEUMATIC AS CALCIFIC AS

COMMISSURES FUSED FREE

LEAFLETS TIPS TO BASE BASE TO TIPS

ORIFICE TRIANGULAR STELLATE SHAPED

AGE OF PATIENT NO PARTICULAR USUALLY ELDERLY

MITRAL VALVE 30% OF MS CASES MAC +

OTHERS TIPS THICKENED,

CALCIFIED (INEXTREME)

TIPS ARE FREE (CALCIFIC

NODULES CAN BE

PRESENT not at TIPS)

How to Assess Aortic Stenosis

Aortic stenosis

Valvular AS is most common.

Goals of echocardiographic evaluation of this condition

Establishing a diagnosis.

Defining the cause. level of obstruction

Quantifying the severity.

Evaluation of coexisting valvular lesions

Assessing LV function.

In patients with known AS, for routine annual evaluation of

asymptomatic severe AS, reevaluation in case of change in clinical

status.

It is not recommended to annually reevaluate asymptomatic mild AS,

unless there is change in clinical status.

Reduced LV function - alters the relationship between transvalvular

pressure gradient and aortic valve area, complicating the quantitative

determination of severity.

Also need to be assessed are

Proximal aortic dilation.

Coexisting mitral valve disease

Measurement of PAP.

M Mode- Normal aortic valve

Maximal aortic cusp separation (MACS)

Vertical distance between right CC and non CC during systole

M Mode- Aortic Stenosis

Aortic valve area MACS Measurement Predictive value

Normal AVA >2Cm2 Normal MACS >15mm 100%

AVA>1.0 > 12mm 96%

AVA< 0.75 < 8mm 97%

Gray area 8-12 mm …..

DeMaria A N et al. Circulation.Suppl II. 58:232,1978

Limitations

Single dimension

Asymmetrical AV involvement

Calcification / thickness

↓ LV systolic function

↓ CO status


M mode of Aortic valve in

LV dysfunction

M mode of AS with AR

Sub aortic membrane

Calcific AS

Qualitative information of stenosis

by 2D echo

Thickened calcified cusps that display preserved mobility define

aortic sclerosis (peak doppler velocity of 2.5 m/sec).

Heavily calcified cusps with little or no mobility suggest severe aortic

stenosis.

If one cusp is seen to move normally, critical aortic stenosis has

been excluded.

Can lead to overestimation of severity.

To be combined with doppler assessment.

Doppler assessment

Pratical noninvasive method for determining the pressure gradient

across the stenotic aortic valve.

Maximal jet velocity through the stenotic valve.

Simplified Bernoulli equation – peak instantaneous gradient (validated

both in invitro and clinically).

Correlates well with simultaneous measurements obtained by

invasive means.

Maximal jet velocity through the stenotic orifice to be recorded for an

accurate assessment, irrespective of the view taken.

“ Aortic jet velocity alone is the strongest predictor of clinical

outcome,the most reliable and reproducible measure for

serial follow up studies and a key element in decision

making about the time of valve replacement.”

Higher signal to noise ratio - CW doppler

As blood accelerates through the valve, peak velocity coinicides

temporally with maximal pressure gradient.

Peak velocity usually occurs in mid systole.

As AS worsens, velocity tends to peak later in systole and the shape

becomes more rounded and less peaked.

Late peaking jets are also characteristic of dynamic sub aortic

obstruction as in HOCM.

Apical five chamber view, suprasternal view, right parasternal view to

be used for assessment.

Rarely subcostal view, left parasternal window.

Align the doppler beam with the direction of flow of the stenotic jet.

Failure to do this – underestimation of severity.

Color doppler may be used to improve alignment.

Highest jet velocity obtained should be used for calculation of

gradient.

Intercept angle

Parallel intercept angle between direction of the jet and the ultrasound

beam.

Cosine = 1

Intercept angles within 15 of parallel – will result in an error in

velocity of 5% or less

Intercept angle of 30 - error of 30%

This will result in even larger error in calculated pressure gradient.

Other high velocity systolic jets that may

be mistaken for aortic stenosis

Subaortic obstruction(fixed or dynamic)

Mitral regurgitation

Tricuspid regurgitation

Ventricular septal defect

Pulmonic or branch pulmonary artery stenosis

Subclavian artery stenosis

Maximal gradient is derived from the equation.(simplified

bernoulli equation)

P(in mmHg) = 4v²

v = maximal jet velocity expressed in meters per

second.

Distal velocity is sufficiently greater than the proximal

velocity that the latter can be ignored.

In cases where the proximal velocity is greater than 1.5m/sec and

the distal velocity is modestly elevated(<3.5m/sec),the proximal

velocity cannot be ignored,then

P(in mmHg) = 4(Vmax² - Vproximal²)

Severe AR

Combined valvular and subvalvular stenosis

Mean Pressure Gradient

1.45=

P mean(in mmHg)

It is most often obtained by planimetry of the doppler envelope,which

allows the computer to integrate the instantaneous velocity data and

provide a mean value.

Mean gradient cannot be obtained by squaring the mean velocity.

Mean gradient is linearly related to the maximal gradient, can be

estimated from the formula:

P max +2 mm Hg

Mean gradient is approx. 2/3 rd s of the peak instantaneous gradient.

Both mean and peak gradients to be reported .

Accuracy of Bernoulli equation

Well established in quantification of stenosis pressure gradients.

Doppler gradients tend to be slightly higher than the

corresponding values obtained in the catheterization

laboratory.the difference is due to phenomenon of pressure

recovery,not due to inaccuracy of either technique.

The conversion of potential energy to kinetic energy across a

narrowed valve results in a high velocity and a drop in pressure.

Distal to the orifice, flow decelerates again. Kinetic energy will be

reconverted into potential energy with a corresponding increase in

pressure, the so-called PR.

Pressure recovery

Pressure recovery

In the setting of native aortic valve stenosis, some recovery of

pressure downstream from the vena contracta can be expected.

This occurs as the jet expands and decelerates downstream from the

vena contracta resulting in a lower net pressure gradient compared to

peak pressure gradient.

The net gradient is measured in the catheterization laboratory,

typically as the pressure difference between LV and ascending aorta.

Peak pressure gradient is derived from CW doppler by measuring

the highest velocity within the vena contracta at the level of the

orifice.

In most cases, pressure recovery has a negligible effect on the

accuracy of gradient calculation.

Pressure recovery is greatest in stenosis with gradual distal widening

Aortic stenosis with its abrupt widening from the small orifice to the

larger aorta has an unfavorable geometry for pressure recovery

PR= 4v²× 2EOA/AoA (1-EOA/AoA)

Pressure recovery

Pressure recovery

Pressure recovery is more significant

Small aortic root,ascending aorta(<3.0cm in diameter)*

Domed congenital aortic stenosis

Certain types of prosthetic valves.

Higher pressure gradient by doppler within the vena contracta.

Catheter –derived pressure will be obtained further

downstream,record a lower gradient.

Pressure recovery

Prosthetic valves

Tapered stenosis

Supravalvular AS

coarctation

Discrepancies ,think of ..

1.Technically poor doppler recording

2.Inability to align the interrogation angle parallel to flow also

results in underestimation.

low velocty jets <3m/sec, the error is modest .

Angle less than 20- insignificant degree of underestimation.

Intercept angle increases beyond 20,the magnitude of error

increases rapidly.

Measures velocity over time ,doppler derived data always represent

instantaneous gradient.

In catheterization laboratory,peak to peak gradient is reported which

is often less than the peak instantaneous gradient,they are contrived

and never exist in time..

Mean gradients to be used,correlate well between the catheterization

and echocardiographic data.

Valve gradients are dynamic measurements that vary with HR,loading

conditions,blood pressure and inotropic state.

Overestimation of the pressure

gradient

Mistaken identity of the recorded signal.

Mitral regurgitation jet has a contour similar to that of the jet of

severe aortic stenosis.because of similarities in location and

direction of the two jets,mistaken identity can occur.

Can be avoided by

1.two jets should be recorded by sweeping the transducer back

and forth to clearly indicate to the interpreter which jet is which.

2.timing of the two jets – MR jet is of longer duration,beginning

during isovolumic contraction and extending into isovolumic

relaxation.

Comparing pressure gradients calculated from

doppler velocities to pressures measured at cardiac catheterization.

Comparing pressure gradients calculated from

doppler velocities to pressures measured at cardiac

catheterization.

Currie PJ et al. Circulation 1985;71:1162-1169

Aortic valve area

Continuity equation

Continuity equation

Determination of aortic valve area.

Based on the principle of conservation of mass,the continuity

equation states that the stroke volume proximal to the aortic

valve (within the left ventricular outflow tract) must equal the

stroke volume through he stenotic orifice.

Stroke volume is the product of cross sectional area (CSA)

and time velocity integral (TVI),the continuity equation can be

arranged to yield.

AV area = CSA LVOT TVI LVOT / TVI AS

CSA To measure the CSA of the outflow tract,the diameter of the outflow

tract is generally measured from the parasternal long axis view and the

shape is assumed to be circular.

Area = r²

Small errors in measuring in measuring the linear dimension will be

compounded in the final formula.

The smaller the annulus,the greater is the percentage error introduced

by any given mismeasurement.

Potential factors for errors – image quality,annular calcification(which

obscures the true dimension),non circular annulus(which invalidates

the formula).

Underestimation is more common than overestimation.

TVI of outflow tract/AS

From the apical window

Pulsed doppler imaging

Positioning the sample volume just proximal to the stenotic valve.

(still laminar)

From same transducer position CW doppler imaging should be used

to record the jet velocity envelope.

Using planimetry,the TVI of both can be derived.

If units for the measurement of the outflow tract diameter are

centimeters,the value of the aortic valve area will be centimeters

squared.

AV area = CSA LVOT V LVOT/V AS

Continuity equation has been validated in a variety of invitro and

clinical settings.

Correlates well with the invasive data using the gorlin equation.

Errors – area and flow assessment to be done at the same level.

The point at which flow is laminar in apical view to be taken for the

measurement of TVI of LVOT.

Advantages of continuity equation

Not influenced by the presence of Aortic regurgitation.

Not affected by the stroke volume

“..a determination of aortic valve area is especially

important in patients with significant aortic regurgitation

and/or reduced left ventricular function.”

Limitations of continuity-equation

valve area

Intra- and interobserver variability

AS jet and LVOT velocity 3 to4%.

LVOT diameter 5% to 8%.

When sub aortic flow velocities are abnormal SV calculation at this

site are not accurate

Sample volume placement near to septum or anterior mitral leaflet

Observed changes in valve area with changes in flow rate

AS and normal LV function, the effects of flow rate are minimal

This effect may be significant in presence concurrent LV dysfunction.

Limitations of continuity-equation valve

area

Interplay between velocity, stroke

volume and aortic valve area

Left ventricular systolic dysfunction

Low-flow low-gradient AS includes the following conditions:

Effective orifice area < 1.0 Cm2

LV ejection fraction < 40%

Mean pressure gradient < 30–40 mmHg

Severe AS and severely reduced LVEF represent 5% of AS patients

Vahanian A et al. Eur Heart J 2007;28:230–68.

Approaches to quantify stenosis

Another approach to reducing error related to LVOT diameter measurements is removing CSA from the simplified continuity equation.

This dimensionless velocity ratio expresses the size of the valvular effective area as a proportion of the CSA of the LVOT.

Velocity ratio= VLVOT/VAV

In the absence of valve stenosis, the velocity ratio approaches 1, with smaller numbers indicating more severe stenosis.

Velocity Ratio/ Dimensionless index

Aortic valve resistance

flow independent measure of stenosis severity that depends on

the ratio of mean pressure gradient and mean flow rate and is

calculated as

Resistance = P mean / Q mean 1333

Relation between the mean resistance and valve area is given by

the formula:

Resistance = 28 Gradient mean / AV area

Advantages over the continuity equation ,have not been

established.

Stroke Work Loss

Novel approach to calculate severity of aortic stenosis

100 P mean

Left ventricle expends work during systole to keep the aortic

valve open and to eject blood into the aorta.it is less dependent

on the flow compared with other parameters.

A cut off value more than 25% effectively discriminated

between patient experiencing a good and poor outcome.

Calculation of SWL has limited practical application.

P mean +SBP SWL (%) =

Energy loss indexDamien Garcia.et al. Circulation. 2000;101:765-771.

Fluid energy loss across stenotic aortic valves is influenced by

factors other than the valve effective orifice area .

An experimental model was designed to measure EOA and

energy loss in 2 fixed stenoses and 7 bioprosthetic valves for

different flow rates and 2 different aortic sizes (25 and 38 mm).

EOA and energy loss is influenced by both flow rate and AA

and that the energy loss is systematically higher (15±2%) in the

large aorta.

Damien Garcia.et al. Circulation. 2000;101:765-771.

Energy loss coefficient (EOA × AA)/(AA - EOA) accurately

predicted the energy loss in all situations .

closely related to the increase in left ventricular workload than EOA.

To account for varying flow rates, the coefficient was indexed for

body surface area in a retrospective study of 138 patients with

moderate or severe aortic stenosis.

The energy loss index measured by Doppler echocardiography was

superior to the EOA in predicting the end points

An energy loss index >0.52 cm2/m2 was the best predictor of

diverse outcomes (positive predictive value of 67%).

Energy loss indexDamien Garcia.et al. Circulation. 2000;101:765-771.

Aortic valve area -Planimetry

Planimetry may be an acceptable alternative when

Doppler estimation of flow velocities is unreliable

Planimetry may be inaccurate when valve calcification

causes shadows or reverberations limiting identification

of the orifice

Doppler-derived mean-valve area correlated better with

maximal anatomic area than with mean-anatomic area.Marie Arsenault, et al. J. Am. Coll. Cardiol. 1998;32;1931-1937

Aortic valve area - Planimetry

Defining the severity of Aortic stenosis

Normal adults , aortic valve area is between 3.0 and 4.0 cm².

Clinically significant aortic stenosis generally requires the valve area

to be reduced to less than one fourth of normal or between 0.75 and

1.0 cm2.

Relationship between valve area and severity is further influenced by

patient size – aortic valve area of 0.9cm² may be severe in a large

patient but only moderate in a smaller person.

Inconsistent relationship between valve area and symptoms.

ACC/AHA guidelines2014

IIa B

IIa C

Effects of concurrent conditions

on assessment of severity

Left ventricular systolic dysfunction

Left ventricular hypertrophy

Small ventricular cavity & small LV ejects a small SV so that,

even in severe AS the AS velocity and mean gradient may be

lower than expected.

Continuity-equation valve area is accurate in this situation

Hypertension

35–45% of patients

primarily affect flow and gradients but less AVA measurements

Control of blood pressure is recommended

The echocardiographic report should always include a blood

pressure measurement

Aortic regurgitation

About 80% of adults with AS also have aortic regurgitation

High transaortic volume flow rate, maximum velocity, and

mean gradient will be higher than expected for a given valve

area

In this situation, reporting accurate quantitative data for the

severity of both stenosis and regurgitation

Effect of concurrent conditions contd…

Mitral valve disease

With severe MR, transaortic flow rate may be low resulting in a

low gradient .Valve area calculations remain accurate in this

setting

A high-velocity MR jet may be mistaken for the AS jet. Timing

of the signal is the most reliable way to distinguish


High cardiac output

Relatively high gradients in the presence of mild or moderate AS

The shape of the CWD spectrum with a very early peak may help to

quantify the severity correctly

Ascending aorta

Aortic root dilation

Coarctation of aorta


Provides information on the changes in aortic velocity, mean

gradient, and valve area as flow rate increases.

Measure of the contractile response to dobutamine

Helpful to differentiate two clinical situations

Severe AS causing LV systolic dysfunction

Moderate AS with another cause of LV dysfunction

Stepwise infusion of dobutamine from 5 to 20 g/kg/min( in an

effort to increase the stroke volume).

Dobutamine stress Echo

An increase in valve area during infusion to > 1.0cm2 is

consistent with mild to moderate stenosis..

True aortic stenosis is assosciated with a fixed valve area that

will not change with dobutamine infusion.

Dobutamine infusion will increase the maximal velocity of both

the outflow tract and jet proportionally. ratio of peak velocity in

the outflow tract and of the jet will remain the same.

In milder forms of stenosis,the increase in the outflow tract will

be much greater than that of the jet (due to increase in valve

area).ratio of outflow tract to jet velocity will increase compared

to the baseline.

Another possible response to dobutamine is a failure of the left

ventricle to augment,in which case neither the gradient not the

valve area changes significantly.

This response is assosciated with a poor overall prognosis and

raises the possibility of concurrent CAD.

A low dose starting at 2.5 or 5 ủg/kg/min with an incremental

increase in the infusion every 3–5 min to a maximum dose of

10–20 ủg/kg/min

The infusion should be stopped as soon as

Positive result is obtained

Heart rate begins to rise more than 10–20 bpm over

baseline or exceeds 100bpm


Role in decision-making in adults with AS is

controversial and the findings recommend as reliable

are

Stress findings of severe stenosis

AVA<1cm²

Jet velocity>4m/s

Mean gradient>40mm of Hg

Nishimura RA et al. Circulation 2002;106:809-13.

Lack of contractile reserve-

Failure of LVEF to ↑ by 20% is a poor prognostic sign

Monin JL et al. Circulation 2003;108:319-24..


TEE

Transducer facing anteriorly and horizontally (0) in mid

esophagus.

Pulling transducer up – ascending aorta,right pulmonary

artery.

120 - reverse parasternal long axis TTE view.

Transgastric level – transducer 180 - descending aorta.

Atheroma garding

Aortic aneurysm

Aortic dissection

3D ECHO

Strain imaging

Global longitudinal strain by speckle tracking may be a more robust

measure of systolic function in patients with severe aortic stenosis.

A longitudinal strain less than 15.9% significantly predicted those at

higher risk of death,symptoms or need for surgery during follow up,as

opposed to EF,which had no discriminatory ability.

During TAVI

After prosthetic valve implantation

Assessing the severity of stenosis

PPM

Pressure recovery

EOA in patients with pressure recovery.

ECHOCARDIOGRAPHIC EVALUATION OF AORTIC STENOSIS

Education

Transcript of ECHOCARDIOGRAPHIC EVALUATION OF AORTIC STENOSIS