‘How I do’ CMR in valvular heart disease Dr. Saul Myerson Clinical Lecturer in Cardiovascular Medicine For 02/2007 This presentation posted

‘‘How I do’ CMR in valvular heart How I do’ CMR in valvular heart diseasedisease

Dr. Saul MyersonClinical Lecturer in Cardiovascular Medicine

For www.scmr.org 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)

© Saul Myerson 2007

Advantages of CMRAdvantages 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


Standard imaging for all studiesStandard 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


LV and RV functionLV and RV function

Gold standard accuracy for

volumes, mass & 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


Specific valve lesions - overviewSpecific valve lesions - overview

• Aortic valve disease

• Mitral valve disease

• Pulmonary stenosis & regurgitation

• Tricuspid regurgitation

• Complex lesions

– Mixed stenosis/regurgitation

– Multiple valves


Aortic stenosis (1)Aortic stenosis (1)

• 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

SA pilot LVOT view Coronal LVOT view



Choose the best LVOT view for in-plane flow assessment (the one with

the best view of the core jet)



• 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



• 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

Valve tips in systole – area = 1.0cm2

Need still image of valve in systole here, including planimetry



• 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

Advantages of CMR:


• Through-plane flow measurement

• Allows quantification of regurgitation

Aortic regurgitationAortic regurgitation


Aortic regurgitation (2)Aortic regurgitation (2)

+218 mls - 52 mls (24% regurgitant fraction)


Aortic regurgitation (3)Aortic regurgitation (3)

• Quantification allows more accurate assessment of severity

(echo parameters less precise)

• More detail required on how quantification fits into clinical practice


Aortic diseaseAortic 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)


Mitral regurgitationMitral regurgitation

Standard methods of quantification are indirect:

1) Regurgitant flow = LVSV - Ao systolic flow(independent of other valve lesions)

2) Regurgitant flow = LVSV - RVSV


Mitral stenosisMitral 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


Mitral stenosis (2)Mitral stenosis (2)

Planimetry of the MV tips:


Pulmonary stenosisPulmonary stenosis

• Good visualisation of pulmonary valve motion

• Accurate velocity assessment

• RVOT sizing for potential surgery / balloon valvuloplasty / percutaneous valve replacement

RVOT planned from transverse slicesHorizontal RVOT planned from previous RVOT


Pulmonary regurgitationPulmonary 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)


Pulmonary valve disease (3)Pulmonary valve disease (3)

CMR is also important for:

• determining RV mass & volumes

• assessing RVOT morphology

Dilated RV secondary to chronic PR


• Supravalvular stenosis with previous surgical widening

• Now recurrent supravalvular stenosis & valvular regurgitation

• Dilated post-stenotic pulmonary artery

Complex pulmonary diseaseComplex pulmonary disease


Tricuspid diseaseTricuspid disease

• 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

Severe TR (note low velocity causes minimal turbulence from dephased spins).

Also has pericardial effusion


Multiple valve diseaseMultiple valve disease

Detailed assessment of severity of each lesion & LV function

Proceed sequentially through assessment of each lesion, including LV/RV funciton assessment

Mixed aortic and mixed mitral valve disease

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‘How I do’ CMR in valvular heart disease Dr. Saul Myerson Clinical Lecturer in Cardiovascular Medicine For 02/2007 This presentation posted