Mitral Valve-in-Valve Implant of a Balloon-Expandable Valve Guided by 3-Dimensional Printing

Abstract

Background: Our goal was to explore the role of 3-dimensional (3D) printing in facilitating the outcome of a mitral valve-in-valve (V-in-V) implant of a balloon-expandable valve.

Methods: From November 2020 to April 2021, 6 patients with degenerated mitral valves were treated by a transcatheter mitral V-in-V implant of a balloon-expandable valve. 3D printed mitral valve pre- and post-procedure models were prepared to facilitate the process by making individualized plans and evaluating the outcomes.

Results: Each of the 6 patients was successfully implanted with a balloon-expandable valve. From post-procedural images and the 3D printed models, we could clearly observe the valve at the ideal position, with the proper shape and no regurgitation. 3D printed mitral valve models contributed to precise decisions, the avoidance of complications, and the valuation of outcomes.

Conclusions: 3D printing plays an important role in guiding the transcatheter mitral V-in-V implant of a balloon-expandable valve.

Clinical trial registration: ClinicalTrials.gov Protocol Registration System (NCT02917980).

Keywords: 3-dimensional printing; balloon-expandable valve; implant; mitral valve; valve-in-valve.

Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Copyright © 2022 Mao, Liu, Ma, Jin, Li and Yang.

Figures

Figure 1

Assessment of computed tomography angiography before the procedure using Circle Cardiovascular Imaging CVI42 software (e.g., data for patient 6). (A) Annular area of the prosthetic mitral valve was 4.26 cm2. (B) The left ventricle was 71.65 mm in the long axis and 47.13 mm in the short axis, and the left atrium was 58.80 mm in the long axis and 60.24 mm in the short axis. (C) The left and right axes of the left ventricle and left atrium were 56.54 mm and 65.36 mm, respectively. (D) By simulating a 26-mm valve, the relationship between the stent and the neo-LVOT could be observed. (E) The area of the neo-LVOT was 5.62 cm2 after simulating the process of implanting the valve. (F) The projection angle of the released valve implanted by trans-septal access is RAO52, CAU5.

Figure 2

Characteristics of the Prizvalve balloon-expandable valve. (A) The 4 main sizes: 20, 23, 26, and 29 mm. (B) The 2 types of delivery systems (14/16F). (C) The adjustable curved introducer.

Figure 3

A 3-dimensional printed model was used to simulate the procedure in the bench test (e.g., data for patient 5). (A–C) 3-Dimensional printed model from the plane of the ascending aorta, the left atrium, and the right atrium, respectively. (D–F) An atrial septal puncture was simulated: The catheter went through the atrial septum and released the balloon-expandable valve successfully (the yellow arrows point to the puncture point). (G) The Vernier caliper was used to measure the inner diameter of the biological annulus. The result (24.14 mm) was equal to the result from the assessment made using computed tomography angiography. (H,I) Released valve from the plane of the left ventricular outflow tract and the left atrium.

Figure 4

Transesophageal echocardiography (TEE) and digital subtraction angiography images show that the procedure achieved good results (e.g., data from patient 2). (A) Preprocedural TEE displays a large amount of colorful blood flow at the mitral valve. (B) The delivery system is positioned in relation to the mitral valve via the atrial septum. (C) After adjusting the position and the coaxiality, the balloon-expandable valve is inflated. (D) After expansion, the stent is fully unfolded. (E) When the guide wire is withdrawn, digital subtraction angiography shows that the position and shape of the mitral valve are ideal and that the stent fits closely to the valve. (F) Post-procedural TEE shows that the balloon-expandable valve is properly closed, with no paravalvular regurgitation.

Figure 5

Assessment of 3-dimensional (3D) reconstruction is completed by using post-procedural computed tomographic data (e.g., data for patient 2). (A–C) 3D reconstruction from the plane of the left atrium, the left ventricle, and the ascending aorta, respectively. (D–F) The 3D printed model from the plane of the left atrium, the left ventricle, and the ascending aorta, respectively. The yellow area represents the frame of the degenerated valve, and the black area is the frame of the balloon-expandable valve.

Figure 6

(A–D) Changes in mitral valve function from baseline to 360 days. (EF, ejection fraction; PVL, paravalvular leak; MR, mitral regurgitation; MV, maximal diastolic velocity through mitral valve; PGMEAN, mean diastolic gradient through mitral valve).