Objectives: To evaluate a new transapical system which utilizes a novel designed positioning element and a two-step positioning mechanism for easy and accurate implantation of transcatheter valves.
Background: Transcatheter aortic valve implantation is an important treatment option for non-surgical patients with severe aortic stenosis. However, accurate placement of the transcatheter valve remains challenging.
Methods: Self-expandable aortic valve prosthesis with a flexibly connected, annulus-like positioning element was implanted through a transapical approach in 12 pigs. The positioning element was separated and can be released independent of the valve prosthesis. During valve implantation, firstly, the positioning element was unsheathed and fixed into the aortic sinus. Then, the prosthetic valve was guided to an anatomically oriented position and deployed. Six animals were followed up to 180 days.
Results: With the help of the positioning element, all 12 valves were successfully deployed at the anticipated site. The valve release procedure took an average of 7.3 ± 2.5 min. The mean transvalvular pressure gradient was 2.8 ± 1.1 mm Hg at valve deployment. Of the six chronic animals, the mean transvalvular pressure gradient was 3.0 ± 1.0 mm Hg on day 7, and 2.9 ± 1.6 mm Hg on day 180 (P = 0.91). No migration, embolization, or coronary obstruction was observed during surgery and at necropsy. Pathological examination showed anatomically correct positioning of the prosthetic valve without signs of thrombosis or calcification.
Conclusions: In this study, we confirmed the feasibility of the J-Valve transapical system for transapical implantation through a two-step process. Satisfactory hemodynamic and pathological performance during a follow-up of 180 days was demonstrated. © 2016 Wiley Periodicals, Inc.
Keywords: anatomically correct positioning; preclinical evaluation; transapical aortic valve implantation; two-step positioning mechanism.
© 2016 Wiley Periodicals, Inc.