Current state of transcatheter mitral valve implantation in bioprosthetic mitral valve and in mitral ring as a treatment approach for failed mitral prosthesis

Deformation of transcatheter heart valves with mitral valve-in-valve

BACKGROUND

The use of oversizing in mitral valve-in-valve (MViV) procedures can lead to non-uniform expansion of transcatheter heart valves (THV). This may have implications for THV durability.

AIMS

The objective of this study was to assess the extent and predictors of THV deformation in MViV procedures.

METHODS

We examined 33 patients who underwent MViV with SAPIEN prostheses. The extent of THV deformation (deformation index, eccentricity, neosinus volume, asymmetric leaflet expansion and vertical deformation) and hypoattenuating leaflet thickening (HALT) were assessed using cardiac computed tomography (CT), performed prospectively at 30 days post-procedure. For descriptive purposes, the THV deformation index was calculated, with values >1.00 representing a more hourglass shape.

RESULTS

Non-uniform underexpansion of THV was common after MViV implantation, with a median expansion area of 74.0% (interquartile range 68.1-84.1) at the narrowest level and a THV deformation index of 1.21 (1.13-1.29), but circularity was maintained with eccentricity ranging from 0.24 to 0.28. The degree of oversizing was a key factor associated with greater underexpansion and a higher deformation index (β=-0.634; p<0.001; β=0.594; p<0.001, respectively). Overall, the incidence of HALT on the 30-day postprocedural CT was 27.3% (9 of 33). Most patients (32 of 33) were on anticoagulation therapy, but the prothrombin time and international normalised ratio (PT-INR) at the time of the CT scan was <2.5 in 23 of 32 patients. Among patients with a PT-INR of <2.5, HALT was predominantly observed with a high THV deformation index of ≥1.18.

CONCLUSIONS

THV deformation, i.e., underexpansion and an hourglass shape, commonly occurs after MViV implantation and is negatively affected by excessive oversizing. Optimising THV expansion during MViV could potentially prevent HALT.

An analytical, mathematical annuloplasty ring curvature model for planning of valve-in-ring transcatheter mitral valve replacement

OBJECTIVES

An increasing number of high-risk patients with previous mitral valve annuloplasty require transcatheter mitral valve replacement due to recurrent regurgitation. Annulus dilation with a transcatheter balloon is often performed before valve-in-ring transcatheter mitral valve replacement, which is believed to reduce misalignment and paravalvular leakage, yet little evidence exists to support this practice. Our objective was to generate intuitive annuloplasty ring analyses for improved valve-in-ring transcatheter mitral valve replacement planning.

METHODS

We generated a mathematical model that calculates image-tracked differential ring curvature to build quantifications for improved planning for valve-in-ring procedures. Carpentier-Edwards Physio M24 and M30 (n = 2 each), Physio II M24 and M26 (n = 3 each), LivaNova AnnuloFlex M26 (n = 2), and Edwards Geoform M28 (n = 2) rings were tested with a 30-mm Toray Inoue balloon inflated to maximum rated pressures.

RESULTS

Curvature variance reduces with larger ring sizes, indicating that larger rings are initially more circular than smaller ones. Evaluated semi-rigid and rigid rings showed little to no difference between pre- and post-dilation states. Annuloflex rings (flexible band) showed a postdilation variance reduction of 32.83% (P < .001) followed by an increase after 10 minutes of relaxation that was still reduced by 19.62% relative to the initial state (P < .001).

CONCLUSIONS

We discovered that balloon dilation does not significantly deform evaluated semi-rigid or rigid rings at maximum rated balloon pressures. This may mean that dilation for these conditions before valve-in-ring transcatheter mitral valve replacement is unnecessary. Our mathematical approach creates a foundation for extended classification of this practice, providing meaningful quantification of ring geometry.

Case report: Transapical transcatheter double valve-in-valve replacement of degenerated aortic and mitral bioprosthetic valves with limited radiopaque landmarks

A 67-year-old male patient who had undergone double valve replacement 11 years before presented with severe dyspnea to our department. The bioprosthetic aortic and mitral valves have failed. Because of the high risk of redo surgery. We perform a simultaneous transapical transcatheter valve-in-valve replacement of degenerated aortic and mitral bioprosthetic valves with limited radiopaque landmarks using the second-generation self-expanding J-valve. The post-operative course was stable and the patient was discharged on post-operative day eight.

Transcatheter Mitral Valve-in-Valve Implantation with the Balloon-Expandable Myval Device

Background: The vast majority of transcatheter valve-in-valve (ViV) mitral procedures have been reported with the SAPIEN family. We aimed to report the preliminary experience with the Myval balloon-expandable device in this setting. Methods: Multicenter retrospective study of high-risk surgical patients with mitral bioprosthesis degeneration undergoing transcatheter ViV implantation with Myval device. Results: A total of 11 patients from five institutions were gathered between 2019 and 2022 (age 68 ± 7.8, 63% women). The peak and mean transvalvular gradients were 27 ± 5 mmHg and 14.7 ± 2.3 mmHg, respectively, and the predicted neo-left ventricular outflow tract (neo-LVOT) area was 183.4 ± 56 mm2 (range: 171 to 221 mm2). The procedures were performed via transfemoral access in all cases (through echocardiography-guided transeptal puncture (81.8% transesophageal, 11.2% intracardiac)). Technical success was achieved in all cases, with no significant residual mitral stenosis in any of them (peak 7.2 ± 2.7 and mean gradient 3.4 ± 1.7 mmHg) and no complications during the procedure. There were no data of LVOT obstruction, migration, or paravalvular leak in any case. Mean hospital stay was 3 days, with one major vascular complication and no stroke. At 6-month follow-up, there was one case with suboptimal anticoagulation presenting an increase in the transmitral gradients (mean 15 mmHg) that normalized after optimization of the anticoagulation, but no other relevant events. Conclusions: Transseptal ViV mitral implantation with the balloon-expandable Myval device was feasible and safe avoiding redo surgery in high-risk patients with bioprosthesis degeneration.

Simultaneous transcatheter tricuspid and mitral valve-in-valve replacement for the treatment of degenerated bioprosthetic valves

Transcatheter valve-in-valve replacement has become a viable option for patients with degenerated bioprosthetic valves at high risk for redo surgery. We report a case of a patient who had degenerated mitral and tricuspid bioprosthesis causing severe tricuspid and mitral regurgitation. We performed simultaneous mitral and tricuspid valve-in-valve replacement via a transfemoral approach. Although the data on performing both valve-in-valve procedures are limited, this case demonstrated that these procedures can be safely done as a single procedure.