1. ‘How I do’ CMR in valvular heart disease
Dr. Saul Myerson
Clinical Lecturer in Cardiovascular Medicine
For 02/2007
This presentation posted for members of scmr as an educational guide – it represents the views and practices of the author, and not necessarily those of SCMR.
University of Oxford Centre for Clinical Magnetic Resonance Research
(OCMR)

2. Advantages of CMR
All areas of the body accessible - free choice of imaging planes with no ‘hidden’ sections
Range of imaging techniques – anatomical, cine, angiography, flow
Quantification of flow and thus valve lesion severity
3D imaging with angiography
No ionising radiation
Other techniques (Echo) do have strengths, esp. in the acute setting

3. Standard imaging for all studies
Long axis planes – HLA, VLA, LVOT, LVOT coronal, (RVOT +/- RV inflow if right-sided lesions)
Need two perpendicular views of the valve(s) in question
LV & RV function

4. LV and RV function
This is important for assessing the impact of the valve lesion on the LV / RV and should be performed in all cases
See How I do a CMR volume study by James Moon, here
Gold standard accuracy for
volumes, mass & function

5. Specific valve lesions - overview
Aortic valve disease
Mitral valve disease
Pulmonary stenosis & regurgitation
Tricuspid regurgitation
Complex lesions
Mixed stenosis/regurgitation
Multiple valves

6. Aortic stenosis (1) SA pilot LVOT view Coronal LVOT view
Plan initial LVOT view from short axis pilot scan, with the plane through the aortic root/valve
The second LVOT (coronal) plane is planned through this, aligned with the stenotic jet. There is often a central core in the jet comprising laminar flow, with turbulent flow (black/low intensity on gradient echo) surrounding this
Align planes with AS jet rather than Ao root

7. Aortic stenosis (2)
Choose the best LVOT view for in-plane flow assessment (the one with the best view of the core jet)

8. Aortic stenosis (3)
Measure the peak velocity, either from the in-plane flow itself, or using the in-plane flow to identify the point of peak velocity and acquire a through-plane flow sequence at this point:
Position for through-plane flow acquisition

9. Aortic stenosis (4)
Measure the valve area by direct planimetry, by acquiring a thin (5-6mm) slice through the tips of the aortic valve in systole, piloted from the 2 LVOT views.
It is important to ensure you are at the tips, as you may overestimate the valve area otherwise
Need still image of valve in systole here, including planimetry
Valve tips in systole – area = 1.0cm2

10. Aortic stenosis (5) Advantages of CMR: Correct alignment with AS jet
Accurate trans-valvular velocity (in-plane / through plane) – avoids underestimation with angulated roots
Valve orifice area (direct planimetry)
LV mass & volumes to assess impact on LV

11. Aortic regurgitation Through-plane flow measurement
Allows quantification of regurgitation

12. Aortic regurgitation (2)
+218 mls
- 52 mls (24% regurgitant fraction)

13. Aortic regurgitation (3)
Quantification allows more accurate assessment of severity
(echo parameters less precise)
More detail required on how quantification fits into clinical practice

14. Aortic disease Don’t forget the aorta in your valve assessment !
Residual root dissection in a patient with a previous type A dissection repair (inter-positional graft)

15. Mitral regurgitation Standard methods of quantification are indirect:
1) Regurgitant flow = LVSV - Ao systolic flow
(independent of other valve lesions)
2) Regurgitant flow = LVSV - RVSV

16. Mitral stenosis Can assess mitral valve area by direct planimetry
Important to ensure correct slice positioning at MV tips (as for echo)
Diastolic flow (volume and velocity) is feasible though temporal resolution is lower than echo

17. Mitral stenosis (2)
Planimetry of the MV tips:

18. Pulmonary stenosis Good visualisation of pulmonary valve motion
Horizontal RVOT planned from previous RVOT
RVOT planned from transverse slices
Good visualisation of pulmonary valve motion
Accurate velocity assessment
RVOT sizing for potential surgery / balloon valvuloplasty / percutaneous valve replacement

19. Pulmonary regurgitation
Quantification of PR
Size & shape of RVOT - ?percutaneous stent-valve replacement
Size & function of RV
Forward flow: 72mls
Regurgitant flow: 27mls (38% regurgitant fraction)

20. Pulmonary valve disease (3)
CMR is also important for:
determining RV mass & volumes
assessing RVOT morphology
Dilated RV secondary to chronic PR

21. Complex pulmonary disease
Supravalvular stenosis with previous surgical widening
Now recurrent supravalvular stenosis & valvular regurgitation
Dilated post-stenotic pulmonary artery

22. Tricuspid disease
Severe TR (note low velocity causes minimal turbulence from dephased spins).
Also has pericardial effusion
Regurgitation can be quantified similarly to mitral regurgitation (RVSV – pulmonary flow)
Stenosis can be assessed with direct planimetry of the tips
RV volumes & function for all

23. Multiple valve disease
Detailed assessment of severity of each lesion & LV function
Mixed aortic and mixed mitral valve disease
Proceed sequentially through assessment of each lesion, including LV/RV funciton assessment