Aortic valve (new)

How common is bicuspid AV?

1/100

Most common type of bicuspid AV and which cusps fused?

Type 1 (2 cusps fused)

Right and left 70-80%

When should LVOT be measured?

Mid systole

When should aortic annulus be measured?

Mid systole

When should sinus of valsalva be measured?

End diastole

When should sinotubular junction be measured?

End diastole

When should proximal ascending aorta be measured?

End diastole

When should AVA be indexed? 3 things

BSA <1.5m²

BMI <22kg/m²

Height <135cm

Peak velocity mild AS?

<2.9m/s

Peak velocity moderate AS?

3-3.9m/s

Peak velocity severe AS?

>4m/s

Mean gradient mild AS?

<25mmHg

Mean gradient moderate AS?

25-40mmHg

Mean gradient severe AS?

>40mmHg

Valve area mild AS?

1.5-2cm²

Valve area moderate AS?

1-1.4cm²

Valve area severe AS?

<1cm²

Dimensionless index severe AS?

<0.25

Normal dimensionless index?

>0.75

2 ways to evaluate LV hypertrophy?

Relative wall thickness

LV mass index (g/m²)

How to calculate relative wall thickness

RWT = (2 * posterior wall thickness end diastole) / LVEDd

Normal LV mass male?

<115g/m²

Normal LV mass female?

<95g/m²

Normal relative wall thickness?

<0.42

Criteria for high gradient AS?

AV <1cm² / <0.6cm²

and

Mean gradient >40mmHg

VMax >4m/s

Criteria for low gradient AS?

SVi <35mL/m²

Mean gradient <40mmHg

3 indications for aortic valve replacement for AS?

Symptomatic

• Severe AS high gradient

• Severe AS low flow

Asymptomatic

• Severe AS and LVEF <50%

Causes of low gradient AS?

Severe MR

Reduced LVEF

Definition of low EF and low gradient AS?

AVA <1cm² or BSA <0.6cm²

LVEF <40%

Mean aortic pressure gradient 40mmHg

What is pseudo severe AS?

AS is mild-moderate

LV dysfunction due to other LV disease

Dose and haemodynamic target of dobutamine stress echo?

10-20mcg/kg/min

HR increase 10-20bpm (not >100)

Stroke volume increase of <20% with dobutamine stress echo?

No flow reserve indeterminate AS

What are the echo findings for pseudo-severe AS after dobutamine stress echo?

Mean grad <40mmHg

AVA increase >0.2cm²

Final AVA >1cm²

5 criteria for preserved LVEF and low gradient AS?

AVA <1cm² or BSA <0.6cm²

LVEF >50%

Mean grad <40mmHg

SVindex <35ml/m²

Severely calcified

3 causes of preserved LVEF, low gradient AS?

Concentric remodelling

Impaired diastolic filling

High afterload

3 additional echo findings consistent with paradoxical AS?

LVEDd <47mm

LVEDi <55ml/m²

RWT >0.50

2 broad classifications of AR? And 2 causes of each?

Primary AR (primary pathology of valve)

• congenital (bicuspid valve)

• Rheumatic heart disease

• Infective endocarditis

Secondary AR (functional)

• Aortic aneurysm with STJ dilatation (HTN, Marfans, inflamm)

• Dissection

Carpentier’s classification of AR?

1. Enlarged aortic root and normal cusps

2a. Cusp prolapse with eccentric AR jet

2b. Eccentric AR without cusp prolapse

3. Poor cusp quality or quantity

4 semi quantitative ways to measure AR?

Vena contracta

Pressure half time

Holodiastolic flow

Regurgitant orifice area

Vena contracta width mild AR?

<3mm

Vena contracta width severe AR?

>6mm

Pressure half time in mild AR?

>500ms

Pressure half time in severe AR?

<200ms

Holodiastolic flow speed in mild AR?

Absent

Holodiastolic flow speed in severe AR?

>20cm/s

Pressure half time in moderate AR?

200-500ms

3 quantative ways to measure AR?

Effective regurgitant orifice area (EROA)

Regurgitant volume

Regurgitant fraction

What is the Effective regurgitant orifice area (EROA) in severe AR?

>30mm²

What is regurgitant volume in severe AR?

>60ml/beat

What is regurgitant fraction in severe AR?

>50%

What jet width to LVOT diameter ratio is indicative of severe AR?

>65%

What jet width to LVOT diameter ratio is indicative of mild AR?

<25%

Where to measure vena contracta?

Immediately distal to regurgitant orifice

What is the Effective regurgitant orifice area (EROA) in mild AR?

<10mm

3D vena contracta area that suggests mild AR?

<30mm²

3D vena contracta area that suggests severe AR?

>50mm²

What jet width to LVOT diameter ratio is indicative of moderate AR?

25-64%

Regurgitant fraction in mild AR?

<30%

Regurgitant fraction in moderate AR?

30-49%

What is the vena contracta?

Narrowest part of the regurgitant jet as it traverses the aortic orifice

What is the vena contracta proportional to and what assumption does it make?

To the EROA

Circular orifice

When is the vena contracts reliable and unreliable?

Reliable - eccentric jet

Unreliable - multiple jets

How is Holodiastolic flow measured?

Descending thoracic aorta. PW Doppler at end diastole

What is a high velocity in the LVOT? And during which phase of cardiac cycle?

>1.5m/s in mid systole

3 causes of dynamic LVOT obstruction?

HOCM

Following MV repair

AVR for AS

Class 1 indications for AV replacement in AR?

Servere AR and symptomatic

Asymptomatic but LVEF <50% and

ESD >50mm

ESD >25mm²

LVEDD >70mm

What Ao diameter is AV replacement recommended regardless of AR severity?

>55mm