Developments in transcatheter aortic bioprosthesis durability

Transcatheter Aortic Valve Replacement with a Self-Expanding Prosthesis

The self-expanding transcatheter heart valve (Medtronic Cardiovascular Corevalve and Evolut) is a supra-annular, trileafet porcine pericardial valves on a diamond lattice nickel-titanium alloy frame. The TAVR device has undergone significant improvements in design and procedural techniques to further increase safety, efficacy, and durability since they it was first released. Unique design characteristics, as well as patient and procedural factors, favor self-expanding over balloon-expandable prostheses in certain situations. The self-expanding transcatheter heart valve has proven to be an excellent option for severe aortic stenosis patients with any level of surgical risk and preliminary data suggest a comparable durability to surgical tissue valves.

Repeated transcatheter aortic valve implantation for the treatment of a degenerated transcatheter aortic valve implantation valve (valve-in-valve technique): a case report

Background

Valve-in-valve transcatheter aortic valve implantation (TAVI) has emerged as a competent alternative for the treatment of degenerated bioprosthetic valves after surgical aortic valve replacement, or during TAVI procedure as a bailout option. Herein, we report a rare case of a self-expandable Medtronic Evolut R valve into a failing Medtronic CoreValve, with the use of modern pre-TAVI imaging screening, suggesting the proper procedural design steps for so complicated implantations.

Case summary

A frail 78-year-old woman with a degenerated Medtronic Core Valve 26 mm bioprosthesis, implanted in 2011 due to severe aortic stenosis, was referred to our hospital due to worsening dyspnoea New York Heart Association III. The screening echocardiography documented severe aortic stenosis, while the classical risk scores were in favour of repeated TAVI (EuroSCORE II 5.67%). Computed tomography measurements and three-dimensional (3D) printing model were of great help for the proper valve selection (Medtronic Evolut R 26 mm), while the use of cerebral protection device (Claret Sentinel) was considered as a necessary part of the procedure. The simultaneous use of fluoroscopy and transoesophageal echocardiogram led to optimal haemodynamic result, confirmed by the discharge echocardiogram, with a significant clinical improvement during the first month follow-up.

Discussion

The main periprocedural concerns remain valve malpositioning, coronary artery obstruction, and high remaining transvalvular gradients. The multimodality pre-TAVI imaging screening may be helpful for precise procedural design. Despite the limited use of 3D models, it is necessary to adopt such tissue-mimicking phantoms to increase the possibility of optimal procedural result.