How to Diagnose and Assess Severity of Mitral Regurgitation by Echo

1
How to Diagnose and Assess Severity of Mitral
Regurgitation by Echo

• Noel Black
• Chief Cardiac Physiologist
• South Eastern Trust

2
Modalities

• 2D and M-Mode
• Colour Doppler
• Pulsed Wave and Continuous Wave Doppler
• 3D

3
M-Mode

• Left atrial dilatation
• Left ventricular dilatation
• Left ventricular volume overload pattern
• Increased D-E amplitude of the mitral valve
  anterior leaflet

4
2-D

• Status of the Mitral Valve Apparatus
• Leaflet prolapse
• Rheumatic disease
• Myxomatous degeneration

5
Organic Aetiology

• Calcification
• Vegetation
• Mass

6
Functional Ischaemic

• Left ventricular impairment
• Chordal/papillary muscle involvement

7
Functional. LV/LA dilatation

• Mitral annular dilatation (normal 2.3-
  0.5cm) A4Ch view
• LA dilatation
• LV dilatation

8
Disease Process

• Aetiology
• Mechanism Non-Ischaemic Ischaemic
• Organic Rheumatic Ruptured PM
• Prolapse
• Endocarditis
• Flail leaflet
• Functional Cardiomyopathy Post-MI

9
Colour Flow Doppler

• 1.Flow distribution (jet size)
• 2.Vena contracta
• 3.PISA

10
1.Flow distribution

• How far the regurgitant jet extends into the LA.
• Trace area of the jet and LA
• Jet area (cm)2
• Severe MR gt10
• Jet area / LA ()
• Severe MR gt40

11
Colour Flow Doppler

• Jet position in relation to the mitral leaflets.
• Evidence of leaflet perforation.
• Multiple or single jets

12
Colour doppler

• The direction of the regurgitant jet
• Centrally
• anteriorly
• posteriorly directed.
• Away from abnormal leaflet.

13
Consider Image quality

• Poor image quality may underestimate severity

14
Consider Jet direction

• Direction of the Jet (entrainment effect)
• Central jet overestimated
• Eccentric jet underestimated

15
Influence of Colour Gain Settings on Colour jet
size -50-60 cm/s
16
Consider Frame rate- Sector and colour box size
17
2.Vena Contracta width

• Narrowest region at the mitral valve level
• 2 planes
• Nyquist 50-60 cm/s
• Zoom to optimise visualisation
• Colour sector as narrow as possible
• Maximal lateral and temporal resolution
• Mild MR
• VC lt0.3cm
• Severe MR
• VC gt0.7cm

18
Consideration

• VC width is inaccurate with multiple jets

19
Consideration

• VC should not be measured in Apical 2Ch view
• Parallel to the mitral orifice.
• Overestimation.

20
3.Proximal Isovelocity surface area (PISA)

• Hemishells
• Flow convergence area
• Increases with severity of regurgitation

21
Calculating (PISA)

• Apical 4Ch view
• Narrow sector width
• Minimise depth
• Zoom
• Adjust Colour Doppler alaising velocity (20-40
  cm/s)

22
PISA

• Measure the radius of the hemisphere. (red/blue
  interface)
• PISA radius 2pr2 (cm2)
• Mild MR lt0.4
• Severe MRgt1.0

23
Consideration

• Non-circular orifice