A systematic review on durability and structural valve deterioration in TAVR and surgical AVR

Fish swim bladders as valve leaflets enhance the durability of transcatheter aortic valve replacement devices

Transcatheter aortic valve replacement (TAVR) has emerged as an effective therapy for inoperable patients with severe aortic stenosis (AS). However, calcification-induced limited durability restricts its application. Fish swim bladders (FSB), which are resistant to calcific degeneration, offer a viable solution to this challenge. In this study, we developed a new TAVR device using FSB as the valve leaflet. Furthermore, the in vitro durability, in vivo performance, and size selection of this TAVR device were assessed by an experimental study and finite element analysis. A self-expandable TAVR device was fabricated by suturing the FSB films into a 23 mm nitinol alloy frame. Further, hemodynamic performance, such as effective orifice area, transvalvular pressure difference and regurgitant fraction, the durability was tested by the pulsatile flow test and accelerated fatigue test, according to the ISO 5840-3. The effect of release size on hydrodynamic performance was also investigated. Finally, the in vivo performance of the TAVR device were examined using a porcine implantation model. The results showed that the strength of the FSB films satisfied the requirements for valve leaflets. The hemodynamic performance of the FSB TAVR device met the requirements of ISO 5840-3 standards. After 400 million cycles, the FSB showed no fiber loss, torn, perforation, or other valve failure phenomena. In porcine models, the devices were well-positioned, functioned well with no stenosis immediately after the operation. Collectively, we successfully developed a TAVR device with FSB as valve leaflets that exhibited good fatigue resistance. STATEMENT OF SIGNIFICANCE: The source of material for the leaflets of commercialized biological heart valves (BHVs) is mainly bovine pericardium, but this material suffers the following problems: large and uneven thickness of the material, the presence of α-Gal and Neu5Gc antigens, and the susceptibility to structural valve degradation (SVD). New material for BHVs leaflets is rarely reported. In this study, we prepared a transcatheter aortic valve (TAV) and performed long-term in vitro and short-term in vivo studies using fish swim bladder (FSB) as the leaflets. The study confirmed that FSB TAV device can complete 400 million fatigue tests and maintain the good morphology of the leaflets, and that it still maintains good functionality after a certain amount of compression, indicating that FSB is a promising material for leaflets.

Predictors of Mid-Term AVNeo Insufficiency

INTRODUCTION

Aortic stenosis (AS) is the most common valvular heart disease and the most common indication for aortic valve replacement in adults. Aortic valve neocuspidization (AVNeo) with fixed autologous pericardium, also known as the Ozaki procedure, is a possible alternative treatment of AS. Autopericardial valves save the dynamics and physiological anatomy of the aortic root, however, the service life of autopericardial leaflets is limited. There is no data about factors that may influence the development of AVNeo insufficiency. Here, we assessed the effect of autopericardial leaflet symmetry on the development of aortic insufficiency after Ozaki procedure.

METHODS

This study included 381 patients with AS who underwent Ozaki procedure. Patients were divided into group 1 (171 patients with symmetric aortic root) and group 2 (210 patients with asymmetric aortic root).

RESULTS

The maximum observation period was up to 65 months. Sixteen cases of aortic insufficiency were detected in group 1, and 33 cases were detected in group 2. Based on the results of Cox regression, the predictors of aortic insufficiency in the late postoperative period are age and asymmetry of neocusps. According to results of Kaplan-Meier analysis, insufficiency of AVNeo in the maximum follow-up period after surgical correction of AS for group 1 patients was significantly lower than for group 2 patients (P=0.006).

CONCLUSION

Asymmetric neocusps increase the risk of aortic insufficiency in the mid-term period after Ozaki procedure. And the older the patients at the time of surgery, the less likely they develop AVNeo insufficiency.

The JenaValve pericardial transcatheter aortic valve replacement system to treat aortic valve disease

Transcatheter aortic valve replacement is a valuable alternative technique to surgery and the spectrum of therapy continues to evolve. The JenaValve Pericaridal transcatheter aortic valve replacement System allows prosthesis fixation in a native, noncalcified aortic annulus with a unique paper clip-like anchorage mechanism. The low rate of paravalvular leakage and permanent pacemaker implantation emphasizes the further widespread use of the JenaValve - despite the limited data available. In May 2021, a CE mark for the transfemoral implantation in both aortic regurgitation and aortic stenosis was granted. However, no data have been published so far. The ongoing ALIGN trials are expected to provide the pending long-term data.