Structural Valve Deterioration after Transcatheter Aortic Valve Implantation Using J-Valve: A Long-Term Follow-Up

Simultaneous management of aortic and mitral regurgitation through one-stage transcatheter aortic valve replacement and transcatheter edge-to-edge repair: case report

This case report presents a 72-year-old male patient who presented with exertional dyspnea for over 10 years, which had progressively worsened over the past 4 months. Transthoracic echocardiography revealed severe aortic and mitral regurgitation, with a left ventricular ejection fraction of 37% and a left ventricular end-diastolic diameter of 64 mm. Despite receiving long-term optimal medical management, there was no improvement in symptoms or severity of valvular regurgitation. Given the relatively high surgical risk associated with double valve replacement in this elderly patient and his preference for minimally invasive procedures, a one-stage transapical aortic valve replacement and transcatheter mitral valve repair using the edge-to-edge technique were planned. The patient was discharged 8 days post-procedure without any complications. At 1-month follow-up, the patient's New York Heart Association (NYHA) functional class had improved to grade II.

Transcatheter Aortic Valve Implantation for Pure Native Aortic Regurgitation: The Last Frontier

Transcatheter aortic valve implantation (TAVI) to treat patients with severe symptomatic aortic stenosis is a well-established procedure. Even though cases series have reported TAVI use in high-risk patients with pure native aortic regurgitation, this is still considered an off-label intervention, especially when the aortic annulus dimensions are beyond the recommended by prosthesis manufacturers. Herein, we provide an updated review regarding the transcatheter treatment of pure native aortic regurgitation and illustrate this issue by presenting a clinical case of a patient with pure aortic regurgitation and a large aortic annulus who received a self-expanding non-dedicated transcatheter heart valve.

Transcatheter Aortic Valve Implantation for Severe Pure Aortic Regurgitation with Dedicated Devices

Aortic regurgitation (AR) is not the most common valvular disease; however, its prevalence increases with age, with more than 2% of those aged >70 years having at least moderate AR. Once symptoms related to AR develop, the prognosis becomes poor. Transcatheter aortic valve implantation for patients with pure severe AR and at prohibitive surgical risk is occasionally performed, but remains a clinical challenge due to absence of valvular calcium, large aortic root and increased stroke volume. These issues make the positioning and deployment of transcatheter aortic valve implantation devices unpredictable, with a tendency to prosthesis embolisation or malposition. To date, the only two dedicated transcatheter valves for AR are the J-Valve (JC Medical) and the JenaValve (JenaValve Technology). Both devices have been used successfully via the transapical approach. The transfemoral experience is limited to first-in-human publications and to a clinical trial dedicated to AR, for which the completion date is still pending.

Artificial Intelligence-Based Spiral CT 3D Reconstruction in Transcatheter Aortic Valve Implantation

To evaluate the clinical application effect of spiral computed tomography (CT) three-dimensional (3D) reconstruction based on artificial intelligence in transcatheter aortic valve implantation (TAVI), a CT 3D reconstruction model based on deep convolutional neural networks (DCNN) was established in this research, which was compared with the model-based iterative reconstruction (MBIR) and used in clinical practice. Then, 62 patients with aortic stenosis (AS) who underwent TAVI surgery were recruited as the research objects. The accuracy, sensitivity, and specificity of the multislice spiral CT scan (MSCT) and transthoracic echocardiography (TTE) in predicting the type of TAVI surgical valve were compared and analyzed. The results showed that the mean absolute error (MAE) (0.01) and root mean square error (RMSE) (0.086) of the MBIR model were higher than the reconstruction model in this research. The structural similarity (SSIM) (0.831) and peak signal-to noise ratio (PSNR) (32.77 dB) of the MBIR model were lower than the reconstruction model, and the differences were considerable ( $P<0.05$ ). Of the valve models selected based on the TTE measurement results, 35 cases were accurately predicted and 27 cases were incorrectly predicted. The accuracy of MSCT was 87.1%, the specificity was 98.84%, and the sensitivity was 92.87%; all of which were significantly higher than TTE ( $P<0.05$ ). In summary, compared with the MBIR reconstruction model, the imaging results of the model established in this research were closer to the real image. Compared with TTE, MSCT had higher accuracy, sensitivity, and specificity and can provide more accurate preoperative predictions for patients undergoing TAVI surgery.

Transapical transcatheter J-valve for aortic regurgitation in dextrocardia situs inversus

A 71-year-old lady with dextrocardia and pure aortic regurgitation was treated with transcatheter aortic valve replacement using the transapical J-valve system. Good clinical and echocardiographic results were demonstrated at one-year follow-up. Herewith we describe this simple, safe, and a minimally invasive aortic valve replacement option for this condition.

Comparison of Procedural and 1-Year Clinical Results of Transcatheter Aortic Valve Implantation Using Prostheses with Different Design of Support Frame

Our study aimed to investigate whether the frame design of transcatheter heart valve (THV) affects the procedural and clinical results of transcatheter aortic valve implantation (TAVI).We retrospectively reviewed 163 patients with aortic stenosis who underwent TAVI using different types of THV (Edwards SAPIEN, n = 31; Venus-A, n = 63; and J-Valve, n = 69). The procedural outcomes and follow-up results for 1-year were compared among groups.The patients who underwent TAVI using J-Valve had a higher mean transaortic pressure gradient than those using SAPIEN or Venus-A after TAVI (1-year follow-up; P = 0.017, P < 0.001, respectively), whereas no difference was observed between the patients with SAPIEN and Venus-A prosthesis (P = 0.150). The incidence of permanent pacemaker implantation was highest in patients with Venus-A (19.0%), followed by SAPIEN (9.7%), and lowest in J-Valve (4.3%) (P = 0.025). No difference was observed in the 30-day mortality rate among the groups (P = 1.000). Moreover, Kaplan-Meier survival analysis revealed that there was no significant difference in the 1-year cumulative patient survival rate among three patient cohorts (log-rank, P = 0.850).The frame design of THVs could affect the valve-related hemodynamics and the incidence of permanent pacemaker implantation in TAVI, whereas it did not influence the survival rate of TAVI patients during 1-year follow-up period. All three THVs provided a convincing short-term outcome for TAVI patients.

Next-generation transcatheter aortic valve implantation

Objective

Transcatheter aortic valve implantation (TAVI) procedures are increasing rapidly, but the durability of tissue valve and periprocedural complications are not satisfactory. Immune reaction to the galactose-α-1,3 galactose β-1,4-N-acetylglucosamine (α-Gal) and conventional processing protocols of cardiac xenografts lead to calcification. Next-generation TAVI needs to be made with α-Gal–free xenografts by multiple anticalcification therapies to avoid immune rejection and enhance durability, and three-dimensional (3D) printing technology to improve the procedural safety.

Methods

Porcine pericardia were decellularized and immunologically modified with α-galactosidase. The pericardia were treated by space filler, crosslinked with glutaraldehyde in organic solvent, and detoxified. The sheep-specific nitinol (nickel–titanium memory alloy) wire backbone was made from a 3D-printed model for ovine aortic root. After it passed the fitting test, we manufactured a self-expandable stented valve with the porcine pericardia mounted on the customized nitinol wire–based stent. After in vitro circulation using customized silicone aortic root, we performed TAVI in 9 sheep and obtained hemodynamic, radiological, immunohistopathological, and biochemical results.

Results

The valve functioned well, with excellent stent fitting and good coronary flow under in vitro circulation. Sheep were sequentially scheduled to be humanely killed until 238 days after TAVI. Echocardiography and cardiac catheterization demonstrated good hemodynamic status and function of the aortic valve. The xenografts were well preserved without α-Gal immune reaction or calcification based on the immunological, radiographic, microscopic, and biochemical examinations.

Conclusions

We proved preclinical safety and efficacy for next-generation α-Gal–free TAVI with multiple anticalcification therapies and 3D-printing technology. A future clinical study is warranted based on these promising preclinical results.