Classification of valve stenosis and regurgitation

Aortic Valve

Aortic valve stenosis - severity

Recommendations for classification of AS severity[1]

	Aortic sclerosis	Mild	Moderate	Severe
Aortic jet velocity (m/s)	≤2.5 m/s	2.6-2.9	3.0-4.0	>4.0
Mean gradient (mmHg)	-	<20 (<30a)	20-40b (30-50a)	>40b (>50a)
AVA (cm2)	-	>1.5	1.0-1.5	<1
Indexed AVA (cm2/m2)		>0.85	0.60-0.85	<0.6
Velocity ratio		>0.50	0.25-0.50	<0.25
aESC Guidelines.[2] bAHA/ACC Guidelines.[3]

Aortic regurgitation - severity

Application of specific and supportive signs, and quantitative parameters in the grading of aortic regurgitation severity[4]

	Mild	Moderate		Severe
Specific signs for AR severity	Central Jet, width < 25% of LVOTς Vena contracta < 0.3 cmς No or brief early diastolic flow reversal in descending aorta	Signs of AR>mild present but no criteria for severe AR		Central Jet, width ≥ 65% of LVOTς Vena contracta > 0.6cmς
Supportive signs	Pressure half-time > 500 ms Normal LV size∗	Intermediate values		Pressure half-time < 200 ms Holodiastolic aortic flow reversal in descending aorta Moderate or greater LV enlargement∗∗
Quantitative parametersψ
R Vol, ml/beat	< 30	30-44	45-59	≥ 60
RF %	< 30	30-39	40-49	≥ 50
EROA, cm2	< 0.10	0.10-0.19	0.20-0.29	≥ 0.30
AR, Aortic regurgitation; EROA, effective regurgitant orifice area; LV, left ventricle; LVOT, left ventricular outflow tract; R Vol, regurgitant volume; RF, regurgitant fraction. ∗ LV size applied only to chronic lesions. Normal 2D measurements: LV minor-axis ≤ 2.8 cm/m2, LV end-diastolic volume ≤ 82 ml/m2 (2). ς At a Nyquist limit of 50–60 cm/s. ∗∗ In the absence of other etiologies of LV dilatation. ψ Quantitative parameters can help sub-classify the moderate regurgitation group into mild-to-moderate and moderate-to-severe regurgitation as shown.

Mitral Valve

Mitral regurgitation - severity

Application of specific and supportive signs, and quantitative parameters in the grading of mitral regurgitation severity[4]

	Mild	Moderate		Severe
Specific signs of severity	Small central jet <4 cm2 or <20% of LA areaψ Vena contracta width <0.3 cm No or minimal flow convergence	Signs of MR>mild present, but no criteria for severe MR		Vena contracta width ≥ 0.7cm with large central MR jet (area < 40% of LA) or with a wall-impinging jet of any size, swirling in LAψ Large flow convergenceς Systolic reversal in pulmonary veins Prominent flail MV leaflet or ruptured papillary muscle
Supportive signs	Systolic dominant flow in pulmonary veins A-wave dominant mitral inflowΦ Soft density, parabolic CW Doppler MR signal Normal LV size∗	Intermediate signs/findings		Dense, triangular CW Doppler MR jet E-wave dominant mitral inflow (E >1.2 m/s)Φ Enlarged LV and LA size∗∗, (particularly when normal LV function is present).
Quantitative parametersφ
R Vol (ml/beat)	< 30	30-44	45-59	≥ 60
RF (%)	< 30	30-39	40-49	≥ 50
EROA (cm2)	< 0.20	0.20-0.29	0.30-0.39	≥ 0.40
CW, Continuous wave; EROA, effective regurgitant orifice area; LA, left atrium; LV, left ventricle; MV, mitral valve; MR, mitral regurgitation; R Vol, regurgitant volume; RF, regurgitant fraction. ∗ LV size applied only to chronic lesions. Normal 2D measurements: LV minor axis ≤ 2.8 cm/m2, LV end-diastolic volume ≤ 82 ml/m2, maximal LA antero-posterior diameter ≤ 2.8 cm/m2, maximal LA volume ≤ 36 ml/m2 (2;33;35). ∗∗ In the absence of other etiologies of LV and LA dilatation and acute MR. ψ At a Nyquist limit of 50-60 cm/s. Φ Usually above 50 years of age or in conditions of impaired relaxation, in the absence of mitral stenosis or other causes of elevated LA pressure. ς Minimal and large flow convergence defined as a flow convergence radius < 0.4 cm and ≤ 0.9 cm for central jets, respectively, with a baseline shift at a Nyquist of 40 cm/s; Cut-offs for eccentric jets are higher, and should be angle corrected (see text). φ Quantitative parameters can help sub-classify the moderate regurgitation group into mild-to-moderate and moderate-to-severe as shown.

Mitral stenosis - severity

Recommendations for classification of mitral stenosis severity[1]

	Mild	Moderate	Severe
Specific findings
Valve area (cm2)	>1.5	1.0-1.5	<1.0
Supportive findings
Mean gradient (mmHg)a	<5	5-10	>10
Pulmonary artery pressure (mmHg)	<30	30-50	>50
aAt heart rates between 60 and 80 bpm and in sinus rhythm.

Mitral valve stenosis - Wilkins score

Assessment of mitral valve anatomy according to the Wilkins score[5]

Grade	Mobility	Thickening	Calcification	Subvalvular Thickening
1	Highly mobile valve with only leaflet tips restricted	Leaflets near normal in thickness (4-5 mm)	A single area of increased echo brightness	Minimal thickening just below the mitral leaflets
2	Leaflet mid and base portions have normal mobility	Midleaflets normal, considerable thickening of margins (5-8 mm)	Scattered areas of brightness confined to leaflet margins	Thickening of chordal structures extending to one-third of the chordal length
3	Valve continues to move forward in diastole, mainly from the base	Thickening extending through the entire leaflet (5-8mm)	Brightness extending into the mid-portions of the leaflets	Thickening extended to distal third of the chords
4	No or minimal forward movement of the leaflets in diastole	Considerable thickening of all leaflet tissue (>8-10mm)	Extensive brightness throughout much of the leaflet tissue	Extensive thickening and shortening of all chordal structures extending down to the papillary muscles
The total score is the sum of the four items and ranges between 4 and 16.

Mitral stenosis - routine measurements

Recommendations for data recording and measurement in routine use for mitral stenosis quantitation[1]

Data element	Recording	Measurement
Planimetry
	- 2D parasternal short-axis view	- contour of the inner mitral orifice
	- determine the smallest orifice by scanning from apex to base	- include commissures when opened
	- positioning of measurement plan can be oriented by 3D echo	- in mid-diastole (use cine-loop)
	- lowest gain setting to visualize the whole mitral orifice	- average measurements if atrial fibrillation
Mitral flow
	- continuous-wave Doppler	- mean gradient from the traced contour of the diastolic mitral flow
	- apical windows often suitable (optimize intercept angle)	- pressure half-time from the descending sLope of the E-wave (mid-diastole slope if not linear)
	- adjust gain setting to obtain well-defined flow contour	- average measurements if atrial fibrillation
Systolic pulmonary artery pressure
	- continuous-wave Doppler	- maximum velocity of tricuspid regurgitant flow
	- multiple acoustic windows to optimize intercept angle	- estimation of right atrial pressure according to inferior vena cava diameter
Valve anatomy
	- parasternal short-axis view
		- valve thickness (maximum and heterogeneity) - commissural fusion - extension and location of localized bright zones (fibrous nodutes or calcification)
	- parasternal long-axis view
		- valve thickness - extension of calcification - valve pliability - subvalvular apparatus (chordal thickening, fusion, or shortening)
	- apical two-chamber view
		- subvalvular apparatus (chordal thickening, fusion, or shortening)
	Detail each component and summarize in a score

Echocardiographic and Doppler parameters used in grading tricuspid regurgitation severity[4]

Parameter	Mild	Moderate	Severe
Tricuspid valve	Usually normal	Normal or abnormal	Abnormal/Flail leaflet/Poor coaptation
RV/RA/IVC size	Normal∗	Normal or dilated	Usually dilated∗∗
Jet area-central jets (cm2)§	< 5	5-10	> 10
VC width (cm)Φ	Not defined	Not defined, but < 0.7	> 0.7
PISA radius (cm)ψ	≤ 0.5	0.6-0.9	> 0.9
Jet density and contour–CW	Soft and parabolic	Dense, variable contour	Dense, triangular with early peaking
Hepatic vein flow†	Systolic dominance	Systolic blunting	Systolic reversal
CW, Continuous wave Doppler; IVC, inferior vena cava; RA, right atrium; RV, right ventricle; VC, vena contracta width. ∗ Unless there are other reasons for RA or RV dilation. Normal 2D measurements from the apical 4-chamber view: RV medio-lateral end-diastolic dimension ≤ 4.3 cm, RV end-diastolic area ≤ 35.5 cm2, maximal RA medio-lateral and supero-inferior dimensions ≤ 4.6 cm and 4.9 cm respectively, maximal RA volume ≤ 33 ml/m2(35;89). ∗∗ Exception: acute TR. § At a Nyquist limit of 50-60 cm/s. Not valid in eccentric jets. Jet area is not recommended as the sole parameter of TR severity due to its dependence on hemodynamic and technical factors. Φ At a Nyquist limit of 50-60 cm/s. ψ Baseline shift with Nyquist limit of 28 cm/s. † Other conditions may cause systolic blunting (eg. atrial fibrillation, elevated RA pressure).

Tricuspid stenosis - severity

Findings indicative of haemodynamically significant tricuspid stenosis[1]

Specific findings
Mean pressure gradient	≥5 mmHg
Inflow time-velocity integral	>60 cm
T1/2	≥190 ms
Valve area by continuity equationa	≤1 cm2
Supportive findings
Enlarged right atrium ≥moderate
DHated inferior vena cava
aStroke volume derived from left or right ventricular outflow. In the presence of more than mild TR, the derived valve area will be underestimated. Nevertheless, a value ≤1 cm2 implies a significant haemodynamic burden imposed by the combined lesion.

Pulmonary Valve

Pulmonary regurgitaion - severity

Echocardiographic and Doppler parameters used in grading pulmonary regurgitation severity[4]

Parameter	Mild	Moderate	Severe
Pulmonic valve	Normal	Normal or abnormal	Abnormal
RV size	Normal∗	Normal or dilated	Dilated
Jet size by color Doppler§	Thin (usually < 10 mm in length) with a narrow origin	Intermediate	Usually large, with a wide origin; May be brief in duration
Jet density and deceleration rate –CW†	Soft; Slow deceleration	Dense; variable deceleration	Dense; steep deceleration, early termination of diastolic flow
Pulmonic systolic flow compared to systemic flow –PWφ	Slightly increased	Intermediate	Greatly increased
CW, Continuous wave Doppler; PR, pulmonic regurgitation; PW, pulsed wave Doppler; RA, right atrium; RF, regurgitant fraction; RV, right ventricle. ∗ Unless there are other reasons for RV enlargement. Normal 2D measurements from the apical 4-chamber view; RV medio-lateral end-diastolic dimension ≤ 4.3 cm, RV end-diastolic area ≤ 35.5 cm2(89). ∗∗ Exception: acute PR § At a Nyquist limit of 50-60 cm/s. φ Cut-off values for regurgitant volume and fraction are not well validated. † Steep deceleration is not specific for severe PR.

Pulmonary stenosis - severity

Grading of pulmonary stenosis[1]

	Mild	Moderate	Severe
Peak velocity (m/s)	<3	3-4	>4
Peak gradient (mmHg)	<36	36-64	>64