Acknowledgments
We thank the help from the staff of Tongji hospital affiliated with
Tongji University, including the department of cardiac echocardiography,
the department of cardiac angiography, and the animal laboratory
management office. Without their help and professional guidance, we
can’t finish this tough research project.
Conflicts of interest
The authors declare that there is no conflict of interest.
Author contribution
Yongxin Zhou supervised the research project, designed the Mitral stent
system, executed the animal experiment, and modified the manuscript.
Kaiqin Wu executed the animal experiment and wrote the manuscript.
Shaorui Gu, Ttiancheng Lu, Zhenchuan Liu, Chenglai Dong, Xin Zhang, and
Haitao Huang were involved in the animal experiments. Shaorui Gu and
Tiancheng Lu also recorded and evaluated the experimental data.
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Figure Legends
Figure 1 Novel mitral valved stent for transcatheter implantation.
(A) Atrial side view of the valve
prosthesis. (B) Ventricular side view of the valve prosthesis. (C-D)
Lateral side view of the valve prosthesis. The main structure of the
valve prosthesis was mainly divided into four parts, including the
atrial flange and the ventricular portion, which are attached to two
opposing extensions (star marker) and two opposing anchors (rectangular
dotted lines). (E) The valve prosthesis is compressed within a delivery
system, with recurrent strings (red arrow) hanging from each pair of
anchors. Anchor (red triangle) is abducted at an angle by the string for
grasping.
Figure 2 Preoperative
echocardiography evaluation before
the animal experiment
(A) The native mitral valve opening during the left ventricular
diastole. (B)The native mitral valve closed
during the left ventricular systole
without valve regurgitation.
Figure 3 Representative fluoroscopy images after valved stent deployment
(A) The valve prosthesis was successfully deployed in the heart
(asterisk labeled prosthesis), and the delivery system was removed and
the ventricular angiography was performed with a pigtail catheter (arrow
pointing to the pigtail catheter).
(B) Ventricular angiography showed that the valve prosthesis was closed
normally in diastole. There is trace paravalvular leakage in this case.
No obvious LVOT obstruction was observed. MV=Mitral valve, LV=Left
ventricle, LA= Left atrium, Ao= Aorta.
Figure 4 Representative echocardiography images after valve deployment
The valve prosthesis was closed well during the left ventricular
systole. (B) Valve prosthesis was opening during the left ventricular
diastole. (LV=Left Ventricle, LA= Left Atrium)
Figure 5 Representative images of necropsy
(A)The pig heart atrium was removed to expose the valve prosthesis. The
atrial flange of the valved stent is located on the mitral annulus.
(B) The left ventricle tissue was dissected to reveal the valve
prosthesis and subvalvular structure. Both anchors successfully clamped
the native leaflet (green arrow) and the valve prosthesis was stable in
the mitral position. There were no LVOT obstruction, valve displacement,
rupture of chordae tendineae or papillary muscle ischemia, or other
subvalvular structural injury. The native mitral leaflets are sandwiched
between anchors and the ventricular body of the stent.
(C) Careful examination of the valve prosthesis revealed no embolism or
nitinol fracture. No leaflets rupture or dislocating was observed.
Tables
Table 1 Procedural data of animal experiments