Transcatheter mitral valve interventions (TMVI) or percutaneous mitral valve interventions are less-invasive, highly technical procedures available for the management of selected patients with mitral valve regurgitation and include several transcatheter mitral valve repair (TMVr) and transcatheter mitral valve replacement (TMVR) techniques 1-6:
transcatheter edge-to-edge repair (TEER)
indirect mitral annuloplasty
direct mitral annuloplasty
chordae tendineae repair or replacement
left ventricular repair
transcatheter mitral valve replacement
transcatheter mitral valve-in-valve or valve-in ring procedure
On this page:
History and etymology
The first transcatheter edge-to-edge repair has been performed in 2003 and has been approved in Europe in 2008 and in the US in 2013 with the last upgrade getting approval in 2019 6-8.
Transcatheter mitral annuloplasty devices have been approved in Europe since 2011, the first technique was an indirect mitral annuloplasty. Direct annuloplasty techniques gained approval in Europe in 2015 7.
Chordae tendineae replacement gained approval in Europe in 2013.
The first transcatheter mitral valve replacement system has been implanted in 2012 and approved for use in Europe in 2020. Transcatheter mitral valve-in-valve and valve-in ring options are approved in Europe and the US.
Indications
Up till now, the only guideline-supported transcatheter mitral valve intervention is the transcatheter mitral valve edge-to-edge leaflet repair and according to the 2020 ACC/AHA and 2021 ESC/EACTS Guidelines for the Management of Valvular Heart disease, this is considered reasonable in severe primary and secondary mitral valve regurgitation in symptomatic patients, who are considered inoperable, or as high surgical risk by a multidisciplinary heart team 6,9,10.
The other devices are under early clinical evaluation and/or development in particular most of the transcatheter mitral valve replacement devices 1,6.
Indirect and direct mitral annuloplasty techniques are indicated in functional mitral regurgitation secondary to ischemic or non-ischemic left ventricular dilation 11,12. Chord replacement is an option for mitral prolapse especially if the posterior leaflet and only one segment are involved 7,13.
Structural requirements
Transcatheter mitral valve interventions require patient evaluation by a multidisciplinary heart team and should be undertaken in a comprehensive heart valve center 6.
Contraindications
Contraindications of transcatheter mitral valve interventions include 9,10:
unfavorable characteristics for transcatheter mitral valve intervention
patients with severe mitral regurgitation who are suitable for mitral valve surgery
futility or short life expectancy <1 year
In addition, there are procedure-related contraindications against individual techniques concerning mitral annular and leaflet anatomy, proximity to the left circumflex artery and the access route.
Procedure
The procedure requires a collaborative multidisciplinary team of general and interventional cardiologists, cardiac valve surgeons, cardiac anesthesiologists, heart failure specialists and imaging experts with appropriate expertise on the subject including valvular heart disease, heart failure, electrophysiology and advanced cardiac imaging 6,9,10.
The procedure will vary with the technique and the device. It will be conducted under fluoroscopic and transesophageal echocardiographic guidance and includes the following steps 1:
establishing access via device-specific access route
advancement of the device
centering and alignment of the device
device deployment
Technique
Choice of technique and device selection will depend on the exact underlying etiology including primary/secondary mitral regurgitation, mitral annular dilation, mitral valve prolapse/flail leaflet as well as the available access route and the experience and preference of the heart team.
Transcatheter mitral valve repair devices can be categorized with regard to the target region such as mitral valve leaflets, mitral annulus, chordae tendineae and the left ventricle 1-5.
Transcatheter edge-to-edge repair
Transcatheter edge-to-edge repair involves clipping of the anterior and posterior leaflets and creation of a double orifice mitral valve in analogy to the Alfieri method 3,4 using a transcatheter guided procedure over transfemoral venous access and a transeptal puncture.
Indirect mitral annuloplasty
Techniques aim at reducing mitral annular dilation with different anchoring or cerclage systems that utilize the coronary sinus to apply a constraint to the mitral annulus. They constitute more simple methods than direct annuloplasty to improve leaflet coaptation 3,11. The access route is transvenous with or without transeptal puncture 11.
Direct mitral annuloplasty
Direct annuloplasty achieves a mitral annular diameter reduction employing direct mitral annular fastening with anchors or pledgets and allows a close approximation to the mitral valve 11,12. Depending on the device access route is transvenous, transarterial or transaortic.
Chordal repair or replacement
Chordal repair and/or replacement techniques involve either the attachment of artificial chords to prolapsed or flail leaflets to the left ventricle under transesophageal echocardiographic guidance with a transapical approach or the transeptal application of a device that pulls the chords together 3,4,13.
Left ventricular repair
Ventricular repair systems aim to reduce secondary functional mitral regurgitation by device implantation into the left ventricle.
Transcatheter mitral valve replacement
Transcatheter mitral valve replacement involves the replacement of the native mitral valve as a whole. Prosthesis stability is achieved utilizing different anchoring mechanisms including apical tether, native leaflet engagement, mitral annular clamping, annular winglets, radial force or external anchors 5. Most transcatheter mitral valve replacement devices are still under development and require a transapical approach with few devices using transvenous access with transeptal puncture 5,6.
Valve-in-valve or valve-in-ring implantation
Transcatheter mitral valve-in-valve or valve-in-ring procedures refer to transcatheter implantation of a mitral prosthesis in the setting of failed surgical mitral valve replacement or repair. Devices come with a transapical or transvenous approach.
Access route
The access route varies with the technique and the implantable device and includes the following options 1-5:
-
transvenous access
via the femoral, internal jugular and subclavian veins
with or without transeptal puncture
transarterial or transaortic access
transapical access
The different access routes feature their advantages and disadvantages, with transvenous and transarterial access being considered less invasive than a transaortic or transapical approach, but the two latter having the advantage of a shorter distance and the transapical approach also a direct route to the mitral valve 5. Most of the transcatheter mitral valve replacements use a transapical approach mostly due to the size of the artificial valve 5.
Complications
Complications of transcatheter mitral valve interventions are dependent on technique, the device and the access.
Peri-procedural or short term complications include 3,14,15:
conversion to open-heart surgery
partial or complete device detachment
valve migration or embolization
cardiac perforation
mitral annular disruption
mitral leaflet or chordal disruption
pulmonary vein perforation
circumflex artery occlusion/myocardial infarction
residual mitral regurgitation
vascular access complications including hemorrhage
atrial fibrillation/atrioventricular block
renal failure
Long term and post-procedural complications include 14,15:
paravalvular leak and hemolysis
valve thrombosis/valvular dysfunction including mitral stenosis
residual moderate to severe mitral regurgitation
cerebral embolic events/stroke
post procedural atrial septal defect
iatrogenic or nosocomial infections
Radiographic features
Pre-procedural imaging
Pre-procedural imaging includes a qualitative and quantitative assessment of mitral regurgitation to assure the indication of the procedure and to determine the underlying etiology (degenerative or functional) 16.
In addition, it serves planning the procedure and subject to the eligible technique it will include not only transthoracic and transesophageal echocardiography but also cardiac CT 5,16-20.
Echocardiography
Transthoracic echocardiography serves the initial evaluation of mitral regurgitation including the etiology and the assessment of left atrial and left ventricular and size and function 16. Patient selection and is usually then done with 2D and 3D transesophageal echocardiography including the assessment of the following parameters 16:
mitral valve area and gradients
location of the pathology
mitral leaflet morphology (thickness, mobility and grasping zone)
coaptation depth
flail width and flail gap
CT
Cardiac CT shines in the evaluation of mitral annular as well as left ventricular anatomy including papillary muscles and the left ventricular outflow tract. In addition, it can give information regarding the proximity of the circumflex artery to the mitral annulus 7. CT analysis is usually done with dedicated software modules and depending on the planned procedure it will include an assessment of the following 5,16-19:
anatomy of the mitral valve and mitral annulus
-
mitral annular dimensions
intercommisural, trigone-to-trigone, septal-to-lateral distances
projected mitral annular area 2D and 3D perimeter
projected distances to the annular plane
mitral annular axis (trajectory)
en-face view and compromise view angulations
mitral leaflet morphology
mitral leaflet and annular calcifications
-
chordae tendineae and papillary muscle anatomy
distance between the heads of the papillary muscles
projected distances to the mitral annulus center and plane
distance to the left ventricular wall
left ventricular outflow tract anatomy including dimensions and aortomitral angulation
valve simulation and neo-left ventricular outflow tract quantification
Peri-procedural imaging
Periprocedural imaging is mainly done with transesophageal echocardiography and fluoroscopy and involves imaging guidance for the following steps 19:
localization of access and ventricular or transseptal puncture
advancement and positioning of the guidewire
advancement and positioning of the delivery system
device deployment
device alignment
device anchoring
Post-procedural imaging
Imaging after transcatheter mitral valve interventions aims at the evaluation of valvular competence and potential complications. It involves the assessment of the following 19:
valvular competence and transmitral gradients
left ventricular outflow tract anatomy and gradients
device position, fitting and stability
leaflet mobility
-
potential complications
paravalvular leak
leaflet thrombosis
device detachment
According to the AHA/ACC transthoracic echocardiography is the recommended baseline imaging modality for postprocedural imaging and periodic monitoring 10.
Transesophageal echocardiography and cardiac CT have slight advantages in the evaluation of left ventricular outflow tract anatomy, device position and complications as leaflet thrombosis.
Radiology report
Pre-procedural evaluation
The radiological report of a pre interventional evaluation will depend on the planned procedure and should include a description of the following 5,16,19:
presence, degree and quantification of mitral regurgitation
mitral annular anatomy including shape and dimensions
mitral leaflet morphology including dimensions
mitral annular and leaflet calcifications
chordae tendineae
papillary muscle anatomy (distance between heads and to the mitral annular plane)
left ventricular and left atrial volumes, dimensions and function
left ventricular outflow tract anatomy
access anatomy
position of the left ventricular apex (distance from sternal midline, intercostal space)
iliofemoral venous anatomy
Post-procedural evaluation
In a postinterventional setting the radiological report should include a description of the following 19:
device position, fitting and stability
leaflet mobility
mitral valvular competence including trans-mitral gradient
left ventricular outflow tract anatomy and gradients
-
possible complications
leaflet thrombosis
paravalvular leak
device detachment
stent fracture
Outcome
Outcomes vary with the procedure and the device 7. Transcatheter edge-to-edge repair with MitraClip features a superior short term safety profile compared to surgical treatment with no difference after five years 21. However, so far surgical repair or reconstruction proved to be more effective in reducing mitral regurgitation after 5 years 22. Many of the approved devices show promising results at short-term follow-up but require further evaluation with clinical trials 7. Chord replacement showed best results with single-segment posterior leaflet prolapse 7.
Unable to process the form. Check for errors and try again.