# Development and preclinical results of a transcatheter aortic valve implant with novel polymeric leaflets

## TL;DR

This paper presents a new TAVI device with polymeric leaflets that showed improved durability and biocompatibility in preclinical tests.

## Contribution

A novel TAVI device with siloxane poly(urethane-urea) leaflets was developed and tested for durability and biocompatibility.

## Key findings

- In vitro tests showed effective hydrodynamics with regurgitant fraction under 6%.
- Preclinical implants in sheep showed stable hemodynamics and no calcification at explant.
- The device demonstrated favorable durability through 200 million cycle fatigue testing.

## Abstract

Current transcatheter aortic valve implantation (TAVI) systems use glutaraldehyde-fixed tissue leaflets, which are prone to structural valve degeneration. Polymeric valves may improve durability, hemocompatibility, and manufacturability. We designed, produced, and evaluated a self-expanding nitinol-framed TAVI device with siloxane poly(urethane-urea) (SiPUU) leaflets and an electrospun SiPUU skirt. Bench testing included frame fatigue to 200 million cycles, hydrodynamics per ISO 5840-3, and flow visualization using particle image velocimetry. Biocompatibility was assessed per ISO 10993. Preclinical evaluation involved nine ovine implants with serial imaging and histology to 90 days. In vitro tests showed EOAs of 1.3–1.5 cm² and 1.7–2.1 cm² (21 and 24 mm annulus, respectively, simulating under expansion), regurgitant fraction <6%, and preserved coaptation. Six animals completed follow-up with stable hemodynamics, no hemolysis, no PVL at implant, and no calcification at explant. The SiPUU-based TAVI demonstrated favorable durability, hydrodynamics, and biocompatibility, supporting further testing and delivery refinement toward first-in-human evaluation. Clinical Trial: N/A