Roberto M. Lang, MD

How Should I Evaluate RV Size and Function?

RV Anatomy• Complex crescent shape• Thin-walled, compliant

chamber• Low pulmonary

resistance / afterload• Sensitive to changes in

afterload- RV dilatation- RV hypertrophy

RV Contraction• Complex contraction

pattern• Inward movement of

the free wall (bellows effect)

• Minor axis shortening• Long-axis shortening

draws the TV towards the apex

Normal

PAH

Severe TR

Left heart disease

PAH

The MANY faces of the RV

Apical 4-chamberRV focused

Apical 4-chamberRV Modified

Apical 4-chamber

Lang RM, Badano LP et al Eur Heart J Cardiovasc Imaging 2015

What We Actually Measure by 2D Echo …

3DE For Assessing the Right Ventricle

Variable RV/RA size, shape and function

Apical 4-chamber

Larger RV minor dimension in the basal segment

RV Focused Apical 4-Chamber

Lateral RV wall, RV maximal longitudinal

distance

RV Modified Apical 4-chamber

• Qualitative RV Size

RV Qualitative Assessment

RV Qualitative Assessment• Mild

– smaller than LV (2/3)

Lang, R et al., J Am Soc Echocardiogr 2005.18; 12:443-7

RA

RV

RV Qualitative Assessment• Mild

– smaller than LV (2/3)

• Moderate– similar in size /

share apexRA

RV

Lang, R et al., J Am Soc Echocardiogr 2005.18; 12:443-7

RV Qualitative Assessment• Mild

– smaller than LV (2/3)

• Moderate– similar in size /

share apex

• Severe– larger than LV ,

forms apex

Lang, R et al., J Am Soc Echocardiogr 2005.18; 12:443-7

RA

RV

Contrast echo- Improve RV visualization

Right Ventricle

• Qualitative• Quantitative

RV SizeRV Function

RV Wall Thickness

RV Dimensions & Area

RV Quantitative Assessment

RV Wall Thickness

• M-mode or 2D• Subcostal view (thicker)• End-diastole• Avoid epicardial fat and coarse

trabeculations

Lang, R et al. J Am Soc Echocardiogr 2015

• More sensitive than EKG• Sensitivity 93%, specificity 95%•Thickness correlates with RV pressure

>3 mm indicates RVH

33±4mm

27±4mm

25±2mm

28±3.5mm

22±2.5mm

A

B

C

RV Dimension & Area

RV Dimension & Area

NL Mild Mod SevereRV EDA (cm2) 11-28 29-32 33-37 ≥ 38

RV ESA (cm2) 7.5-16 17-19 20-22 ≥ 23

Normal RV Abnormal RV

Diastole Systole

Fractional Area Change

(end-diastolic – end-systolic area)end-diastolic area

Diastole Systole

FAC =

Segmental Nomenclature of RV Walls and Coronary Supply

• Qualitative• Quantitative

RV SizeRV Function

RV Wall Thickness

RV Dimensions & Area

RV Quantitative Assessment

RV Function

• Eye-balling• RIMP (RV Index of Myocardial Performance)• TAPSE (Annular Plane Systolic Excursion)• 2D FAC (Fractional Area Change)• 2D RV EF (2D RV Ejection Fraction)• 3D RV EF (3D RV Ejection fraction)• Tissue Doppler Derived Tricuspid Lateral

Annular Systolic Velocity (S’)• Longitudinal Strain and Strain Rate

RV Function

RV Function

• Qualitative– “Eye-Balling” – Correlation 0.85 with

quantitative RVEF (Simpson’s)

– High InterobserverVariability (14.8% ±13%)

Miller, D. J Am Soc Echocardiogr 2004; 17:443-7

RA

RV

RV TAPSEApical 4-chamber RV-focused view

Basal segment & annulus parallel to M-mode cursor

24±3.5, mm

<17, mm

RV FunctionTricuspid Annular Plane Systolic Excursion

Surrogate for global RV systolic function

• 5 mm → 20% EF• 10 mm → 30% EF• 15 mm → 40% EF• 20 mm → 50% EF

– Correlates with RV RNA EF

Kaul, S. Am Heart J 1984; 107:526-31

Lateral Annulus

Longitudinal Function

RV Tissue Doppler S’

S’

Apical 4-chamber RV-focused view

Basal segment & annulus parallel to M-mode cursor

14.1±2.3, cm/s<9.5, cm/s

RV Function

RV FunctionTissue Doppler of Tricuspid Annulus

• Correlates with other measures of global RV systolic function

• Basal segment and annulus must be kept well alignedMeluzin, J. et al. Eur Heart J 2001; 22:340-8.

S’ Velocity: < 9.5 cm/s indicated RV systolic dysfunction

Annular Displacement vs. Time

5

6

7

8

9

10

0 200 400 600 800 1000 1200 1400Time (msec)

RV FunctionSpeckleTracking

RV Free Wall longitudinal Strain

Apical 4-chamber RV-focussed view

Free wall longitudinal strain

-29±4.5, % >-20, %

RV FunctionStrain Imaging

80 patients with PAH (Class III/IV) RV free wall strain >-12.5%

associated with greater disease severity, higher BNP, higher RAP, larger RV volumes

Strain >-12.5% had 61% 1 yr and 57% 2 yr mortality

For every 5% decrease in strain, risk of death increased by 3.3 fold

Sachdev A et al. Chest 2011, 139:1299-1309

Normal Subject PAH Subject

Challenges with 2D Parameters2D Parameter Pros Cons

TAPSE ReproducibleEasy to use

Load dependentAngle dependentAssumes displacement of a single segment represents function of a complex 3D structure

Tei Index ReproducibleNot affected by complex geometry

Load dependentUnreliable in irregular heart rate Falsely low (more normal) when elevated RAP

2D longitudinal strain Angle independentImproved signal to noise with speckle methodAssumes displacement of entire RV

Load dependent

RIMP Index = IVCT + IVRT

Tei, C. et al. J Am Soc Echocardiogr 1996; 9:838-47Roberson, DA and Cui, W. J Am Soc Echocardiogr 2007; 20:764-70

ET

Pulsed Doppler Method Pulsed Tissue Doppler Method

Index of Global RV Function

>0.4 >0.55RV Dysfunction

RV Linear Dimensions

and Area

RV FunctionFractional Area Change

Lang, R et al. J Am Soc Echocardiogr 2005.18; 12:443-7

2D FAC <35% indicates RV systolic dysfunction

• Correlates with MRI RV EF (r = 0.69 - 0.88)• Related to outcome in a number of conditions

Eyeball confirmation is important!

TAPSE = 1.6 cm

RV S’ = 14 cm/s

Moderate-severe TR

RVEF 27%

CMR

RA

RV

LV

LA

PV

RA RV

RV

PV

• Complex geometry• Limited definition of RV

endocardium due to heavy trabeculation

• Retrosternal position of RV can limit windows

• Operator-dependent• Must include infundibulum

(contains up to 25-30% of RV volume)

• Lack of standardization of normal values

Challenges with 2D Echocardiography

3D Echocardiography

Freehand Acquisition

Real-time Acquisition

RT3DE Imaging

S

AP

RV Anatomy

• Inlet

• Apical

• Outlet

RV volume: Multi-modality comparisons

Sugeng L, Lang RM, et al. J Am Coll Cardiol Img 2010; 3:10-18

CCT overestimated and RT3DE underestimated RV volumes compared to CMR

reference.

y = 0.7x

r = 0.81

y = 0.7x

r = 0.81

-150

-100

-50

0

50

100

150

0 100 200 300CMR : ESV (ml)

CC

T - C

MR

: ES

V (m

l)

y = 0.7x

r = 0.81

y = 0.7x +

r = 0.81

-150

-100

-50

0

50

100

150

0 100 200 300 400CMR : EDV (ml)

CC

T - C

MR

: ED

V (m

l)y = 0.7x +

r = 0.81

y = 0.7x

r = 0.81

-40

-20

0

20

40

10 20 30 40 50 60 70CMR : EF (%)

CC

T - C

MR

: EF

(%)

ESV EDV EF

y = 0.7x +

r = 0.81

y = 0.7x

r = 0.81

-150

-100

-50

0

50

100

150

0 100 200 300CMR : ESV (ml)

RT3

DE

- CM

R :

ESV

(ml) y = 0.7x

r = 0.81

y = 0.7x

r = 0.81

-150

-100

-50

0

50

100

150

0 100 200 300 400CMR : EDV (ml)

RT3

DE

- CM

R :

EDV

(ml)

y = 0.7x

r = 0.81

y = 0.7x

r = 0.81

-40

-20

0

20

40

10 20 30 40 50 60 70CMR : EF (%)

RT3

DE

- CM

R :

EF (%

)

Bias: 17 mlLOA: ±63 ml

Bias: 23 mlLOA: ±76 ml

Bias: -9 mlLOA: ±53 ml

Bias: -14 mlLOA: ±73 ml

Bias: -2%LOA: ±15%

Bias: -2%LOA: ±12%

Sugeng L, Lang RM, et al. J Am Coll Cardiol Img 2010; 3:10-18

The 3D RV model

RV-focused 3DRV-focused 2D view

Bias: -11 mlLOA: ± 40 ml

Bias: -0.3 mlLOA: ± 31 ml

Bias: -3.3 %LOA: ± 15 %

RV Volumes and EF

RV EF % 58±6.5

<45

RV EDV/BSA, Men 61.3±13 35-87RV EDV/BSA, Women 53±10.5 32-74

RV ESV/BSA, Men 27±8.5 10-44RV ESV/BSA, Women 22±7 8-36

RV Function Parameter

CC with MRIRVEF (r)

3D RVEF2D RVstrain2D FACS’2D TAPSE2D RV TEI

0.850.670.630.520.470.37

Freed B, Lang RM et al., J Am Soc Echocardiogr 2012: 25 (6), B116

RV Function in PAH

• Easy and quick acquisition

• Independent of geometric assumptions

• Semi-automated border detection

• Dynamic RV cast• 3DE volume, function,

compare well with CMR and are reproducible

• Limited by quality of 3D RV data

• RV mass less reproducible

• Not available on-line

Current RT3DE MethodologyAdvantages Disadvantages