Mitral clip implantation, Echocardiography Perspectives

1. Mitral clip
&
Echocardiography

3. Denton Arthur Cooley
(August 22, 1920 – November 18, 2016)

4. Introduction
▪ Only technique available to alter the mitral valve (MV) morphology,
annulus diameter, and reduce MR.
▪ Alfieri in 1991, surgically sutured the free edges of the mid-portions of
the anterior (A2) and posterior (P2) MV scallops.
▪ Maisano et al. demonstrated that with the Alfieri technique 90 % of
patients with both functional and degenerative MR are free from the
combined endpoint of recurrent MR ≥2+ and re-operation after 5
years.

5. Echo & Mitral Clip
▪ Echocardiography is the essential imaging modality for
MitraClip treatment.
(i) Patient selection
(ii) Guidance of the procedure
(iii) Identification as well as the assessment of complications
(iv) The evaluation of the final result after clip implantation
(v) The assessment at followup of MR severity, left
ventricular (LV) chamber size and function as well as
pulmonary artery pressures.

6. Patient selection Grading of MR severity
▪ MR needs to be moderate to severe (3+) or severe ( 4+).
▪ Chronic severe MR is generally associated with left atrial (LA) and LV
enlargement.
▪ Severe MR as timed by CW Doppler is generally holosystolic.
▪ ‘E’-wave in the mitral inflow is taller than the ‘A’-wave
▪ An ‘E’-wave taller than 1.2–1.5 m/s usually indicates severe

8. MITRAL VALVE ANATOMY ON TEE

9. Determination Of The Morphology
▪ TTE vsTEE
▪ Morphology
▪ Eccentric jet
▪ All pulmonary veins
▪ Detailed anatomy of mitral apparatus
▪ Description of scallops and commissures

10. 10
Anatomic Measurements
▪ Degenerative Mitral Regurgitation (DMR)
–Flail Gap
–FlailWidth
▪ Functional Mitral Regurgitation (FMR)
–Coaptation Length
–Coaptation Depth

13. Posterior Leaflet Length

16. Ideal Valves for Mitral clip
▪ Central origination of MR (A2/P2 segments)
▪ No severe calcification in the grasping area
▪ PML should be long enough to allow secure capturing by the Clip.
▪ No excessive flail width and an excessive flail gap
▪ Some residual coaptation length should exist in functional MR

17. Intermediate suitability
it has been reported that in isolated patients with anatomy outside these
criteria, successful treatment with the MitraClip may be achieved.These
include
–Pathology in the P1 or P3 segment
–MVA 4 cm2 and 3 cm2 with good leaflet mobility
–Mobile posterior leaflet length between 7 and 10 mm, leaflet
restriction in systole

18. Main procedural steps
1.Transseptal puncture
2. Introduction of the Steerable Guide Catheter (SGC) into the left atrium
3. Advancement of the Clip Delivery System (CDS) into the left atrium
4. Steering and positioning of the MitraClip above the mitral valve
5. Advancing the MitraClip into the left ventricle
6. Grasping of the leaflets and assessment of proper leaflet insertion
7. Clip detachment

19. Using 3D TEE Before procedure
▪ Benefits of Orthogonal views
▪ Detailed MV anatomy and function and all components of the mitral
apparatus
▪ Scallop Identification
▪ Identification of clefts, gaps, and perforations
▪ The mitral annulus visulaization

20. ▪ Delivery catheters, wires, devices, and target structures can be
visualized in one single view with 3DTEE
▪ MitraClip positioning perpendicular to the line of coaptation in the
middle segments of the MV.
▪ Should be combination of 2D and 3D
▪ Biner et al, demonstrated that the usage of 2D and 3DTEE in
combination is associated with a remarkable 28% reduction in
procedure times.
Using 3D TEE during procedure

21. Transseptal Puncture
▪ Most important aspects of the MitraClip procedure.
▪ Optimal puncture site is located superiorly and posteriorly
in the interatrial septum (IAS )
▪ ThreeTEE planes are used to determine the correct site:
– Short-axis view at the base for anterior–posterior orientation
– Bi-caval view for superior - inferior orientation
– Four-chamber view to direct the height above the MV.

22. Transseptal puncture
▪ What is tenting ‘tenting’
▪ Height above mitral annulus
– Degenerative 4-5 cm
– Functional 3.5 cm
▪ PFO and ASDs should be avoided

23. Introduction of the Steerable Guide
Catheter (SGC)
3. Continous monitoring to avoid injury
4. Dilator is retrieved first, then extra stiff wire
1. Wire in Pulmonary vein
2. Identify Dilator, SGC

24. Advancement of the Clip Delivery System
(CDS) into the left atrium
▪ The CDS Advanced and then dipped down
▪ Slow advancement to avoid injury
▪ 3DTEE and x-plane views are used to visualize the distance of the CDS from the LA wall

25. Steering and positioning of the MitraClip
above the mitral valve
▪ Medial– lateral Clip adjustments ---intercommissural view
▪ Anterior–posterior adjustments ---long-axis (LVOT) view
▪ Mitral Clip should be perpendicular to the line of coaptation
▪ Opened Clip can be visualized in full length in the longaxis view
▪ No Clip arms should be seen in the intercommissural view
▪ The MitraClip should split the regurgitation jet in both orthogonal views
▪ A single 3D enface-view
X Plane

27. Advancing the MitraClip into the left
ventricle
▪ Maintain same position as previous
▪ Passage across the MV in open state.
▪ Reassess in LV as might rotate
▪ 2DTEE (intercommissural and LVOT)
and 3DTEE views are used

28. Grasping Of The Leaflets And Assessment
Of Proper Leaflet Insertion
▪ After suitable position grasping done in LVOT
view (2D)
▪ 3D has no clear benefit in this part of the
procedure
▪ Longer loop during the grasping
▪ Initial partial closure followed by full
▪ Multiple planes are useful
▪ Insertion of the posterior leaflet is commonly
best seen in the LVOT view
▪ Insertion of the anterior leaflet in the four-
chamber view.

30. Assessment Of Result And Mitraclip Release
▪ Grade of regurgitation
▪ stenosis of the MV
▪ Complications
▪ Effects ofAnesthesia on assessment
▪ Post clip quantitative Doppler evaluation is problematic due to multiple
orifice
▪ Potential overestimation of residualMR in patients with multiple jets.
▪ Artefacts caused by the MitraClip may also alter the findings
▪ Small persistent colour jets, even if multiple, are certainly congruent with
mild MR.

31. Assessment Of Result And Mitraclip Release

32. ▪ Pulmonary vein flow estimation
▪ The PISA method is not validated for multiple MR jets
▪ Regurgitation volume can be calculated
▪ 3D-acquisition of the LV volumes is preferable for the calculation when
available.
▪ Summation of 2D measured venae contracta is not reliable in the presence of
multiple jets.
▪ Measurement of the vena contracta area in 3D echocardiography shows
potential for the quantification of MR with irregularly shaped vena contracta
areas, although currently no reference data are available.
Assessment Of Result And Mitraclip Release

33. Additional parameters
In addition to echocardiography, some other parameters may be
helpful for the evaluation of the severity of residual MR:
▪ LA pressure measurements (V-wave). A decrease or even a
normalization of LA pressures may be seen in case of effective MR
treatment.
▪ Stroke–volume measurements via right heart catheterization
▪ LV angiography to assess the amount of regurgitation by judging the
density and the expansion of the MR jet in the LA.

34. ▪ Mean gradient of up to 5 mmHg is considered acceptable.
▪ Planimetry of the two orifices should be performed, ideally with 3DTEE,
alternatively with 2DTEE in the transgastric short-axis view.
▪ In the EVEREST I and II studies, a planimetric MVA of 1.5 cm2 was
considered criteria for clinically significant mitral stenosis.
▪ Once in place, it has been demonstrated that the MitraClip device did not
result in clinically significant MV stenosis during 2 years followup
Additional parameters

35. Additional MitraClip implantation
▪ Same positioning of clip in LA.
▪ Clip should be Closed during advancement into LV to avoid
entaglement
▪ Fluoroscopy is more helpful thanTEE for the positioning of a
second MitraClip
▪ It should be aligned as parallel as possible to the first Clip.

37. Post-procedural follow-up
For post-procedural follow-up,TTE is usually sufficient. current guidelines
includes
▪ Colour flow Doppler of the MR
▪ MV inflow gradient
▪ Assessment of pulmonary vein flow
▪ Residual ASD evaluation
▪ Systolic pulmonary artery pressure
▪ LV size and volume measurements in systole and diastole
▪ LVEF

38. Thanks for your patience

39. Future Perspectives
Role of 3D echocardiography in the assessment of MR severity may increase in the
future
Major advantage being the ability of this modality to assess vena contracta area
which is most commonly non-circular especially in patients suffering from functional
MR.
Usually, the vena contracta area is quantified in a post-processing step using
planimetry of 3D colour regurgitation jets in orthogonal views.
The 3D derived vena contracta area correlated better with effective regurgitant
orifice area derived from Doppler measurements than 2D vena contracta diameter
measurements.

40. Real-time three-dimensional volume colour flow Doppler was feasible, accurate, and reproducible for mitral inflow and
aortic stroke volume measurements.
During interventional procedures including the guidance of a MitraClip implantation, there is an increasing reliance on 3D
TEE.
A newly developed EchoNavigator system (Philips Healthcare) may facilitate procedural guidance by matching
echocardiographic and fluoroscopic images.
Although only limited clinical data are available at this time, the new features of the EchoNavigator system may support
the understanding of the spatial relation between the Echo and X-ray image, thus makingTissue bridge created by the
MitraClip. Specular
isosceles triangles indicate uniform and symmetrical tension of
the Clip on both leaflets.
946 N. C.Wunderlich and R. J. Siegel
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