State-of-the-Art ReviewEmerging Approaches to Management of Left Ventricular Outflow Obstruction Risk in Transcatheter Mitral Valve Replacement
Central Illustration
Section snippets
Assessment of LVOT Obstruction Risk Before TMVR
The gold standard method for assessment of the LVOT anatomy and procedural TMVR planning is gated cardiac CT angiography, which provides excellent spatial resolution and clear definition of left ventricular structure. All patients being considered for TMVR require a gated cardiac CT assessment for determination of procedural candidacy. An exception to this is patients who have a degenerated mitral bioprosthesis being considered for mitral valve-in-valve therapy, in which case CT may be
Impact of TMVR Design on LVOT Obstruction Risk
The self-expanding double-framed nitinol Tendyne device (Abbott) has a tapered shape in the left ventricular cavity that allows for less protrusion into the LVOT compared with cylindrical-shaped devices.16 The Intrepid device (Medtronic) similarly has a low profile with minimal protrusion into the LVOT, thus lowering LVOT obstruction risk. As a result, the neoLVOT for Tendyne or Intrepid in a given patient will typically be slightly larger than with a cylindrical-shaped valve such as SAPIEN 3
Alcohol Septal Ablation
Alcohol septal ablation was originally developed for treatment of hypertrophic cardiomyopathy (HCM) in the 1980s19 and is recommended as a Class I indication for treatment of severely symptomatic LVOT obstruction refractory to medical therapy.20 The technique involves percutaneous cannulation of the coronary artery in the cardiac catheterization laboratory using a guiding catheter, advancing a 0.014-inch wire and over-the-wire balloon into the septal perforator branch supplying the basal
TMVR Patient Management Algorithm
The approach we use consists of positioning the virtual transcatheter valve in the anticipated implantation location and measuring the virtual THV frame neoLVOT and skirt neoLVOT (Figure 7). When the frame neoLVOT is <200 mm2 and the skirt neoLVOT is <200 mm2, the interventricular septum is assessed to determine whether hypertrophy is present and whether ablation of the basal septum is feasible. We use a diastolic septal thickness cutoff of 10 mm or more to determine whether ablation can be
Future Directions
The neoLVOT management algorithm proposed in this review is currently being used in the prospective MITRAL 2 (MITRAL II Pivotal Trial [Mitral Implantation of TRAnscatheter vaLves]; NCT04408430) and outcomes of this approach will be forthcoming. As experience with LVOT modification techniques in TMVR grows, more data regarding patient selection and efficacy of these approaches will become available. Future study of clinical and anatomical predictors of optimal response to ASA, LAMPOON, and other
Conclusions
Several new and effective techniques are available to help reduce the risk of LVOT obstruction in TMVR.
Funding Support and Author Disclosures
Dr Mahoney has served as a consultant for Edwards Lifesciences and Medtronic. Dr Killu has served as a consultant for Boston Scientific; and has received honoraria from Biosense Webster. Dr. Guerrero has received institutional research grant support from Edwards Lifesciences; and has served as consultant for Abbott Structural Heart and Medtronic. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
References (30)
- et al.
Severe mitral annular calcification: multimodality imaging for therapeutic strategies and interventions
J Am Coll Cardiol Img
(2016) - et al.
1-Year outcomes of transcatheter mitral valve replacement in patients with severe mitral annular calcification
J Am Coll Cardiol
(2018) - et al.
Causes and clinical outcomes of patients who are ineligible for transcatheter mitral valve replacement
J Am Coll Cardiol Intv
(2019) - et al.
Prospective study of TMVR using balloon-expandable aortic transcatheter valves in MAC: MITRAL trial 1-year outcomes
J Am Coll Cardiol Intv
(2021) - et al.
Alcohol septal ablation to prevent left ventricular outflow tract obstruction during transcatheter mitral valve replacement: first-in-man study
J Am Coll Cardiol Intv
(2019) - et al.
Pre-emptive radiofrequency septal ablation to decrease the risk of left ventricular outflow tract obstruction after TMVR
J Am Coll Cardiol Intv
(2020) - et al.
Anterior leaflet laceration to prevent ventricular outflow tract obstruction during transcatheter mitral valve replacement
J Am Coll Cardiol
(2019) - et al.
Tip-to-base LAMPOON for transcatheter mitral valve replacement with a protected mitral annulus
J Am Coll Cardiol Intv
(2021) - et al.
Predictors of left ventricular outflow tract obstruction after transcatheter mitral valve replacement
J Am Coll Cardiol Intv
(2019) - et al.
Multimodality imaging in the context of transcatheter mitral valve replacement: establishing consensus among modalities and disciplines
J Am Coll Cardiol Img
(2015)
Predicting left ventricular outflow tract obstruction despite anterior mitral leaflet resection: the "skirt NeoLVOT"
J Am Coll Cardiol Img
Severe mitral annular calcification: first experience with transcatheter therapy using a dedicated mitral prosthesis
J Am Coll Cardiol Intv
Percutaneous transcatheter mitral valve replacement: first-in-human experience with a new transseptal system
J Am Coll Cardiol
Non-surgical myocardial reduction for hypertrophic obstructive cardiomyopathy
Lancet
2020 AHA/ACC guideline for the diagnosis and treatment of patients with hypertrophic cardiomyopathy: a report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines
J Am Coll Cardiol
Cited by (6)
Postsurgical Transcatheter Mitral Valve Replacement
2024, Interventional Cardiology ClinicsTransseptal BATMAN for High-Risk Valve-in-Ring Procedures: A Case Series
2024, JACC: Case ReportsTranscatheter Mitral Valve Replacement: Treatment Planning With Computed Tomography
2024, Seminars in RoentgenologyTranscatheter Aortic Valve Implantation to Treat Degenerated Aortic, Mitral and Tricuspid Bioprosthesis
2024, Journal of Clinical MedicineCurrent Percutaneous Approaches to Treat Mitral Valve Regurgitation
2023, Current Treatment Options in Cardiovascular MedicineUpdate on Transcatheter Treatment of Mitral and Tricuspid Valve Regurgitation
2023, Current Cardiology Reports
The authors attest they are in compliance with human studies committees and animal welfare regulations of the authors’ institutions and Food and Drug Administration guidelines, including patient consent where appropriate. For more information, visit the Author Center.