Small patients – Big needs: A material-based approach to develop miniaturised valves for congenital heart diseases

Bioactive Materials, vol. 57, pp. 430–444

Abstract

Paediatric valve replacements cannot be built by simply scaling down bigger-sized valve implants. Innovative approaches that combine novel material systems, processing technologies, and device designs are needed to develop adaptable, durable, and biocompatible miniaturised solutions tailored to the paediatric population with congenital heart diseases. In response to that medical need, in this work, we have developed miniaturised valves following a biohybrid approach that combines synthetic components with bioinspired materials to exploit the optimal properties of each. Specifically, the valve was composed of (i) an electrospun synthetic polymer to provide stability, (ii) protein-engineered elastin to ensure flexibility and low thrombogenicity, and (iii) a tailor-made stent to enable minimally invasive implantation. Our valve implant demonstrated outstanding maximum strain values over 300 %, maximum stresses exceeding 6 MPa, and the ability to withstand burst pressures over 1000 mmHg. Blood compatibility tests revealed lower platelet activation than ePTFE, which is a material used in clinical applications. The hydrodynamics of the miniaturised valve met the standards outlined in the ISO guidelines with regurgitation fractions below 15 % and complete valve closure, indicating excellent functionality. Overall, we have established a material-based approach to address the clinical demand for small valves for children suffering from congenital heart diseases.

Authors 8

1. Selina M. Sonntag Aachen Department of Biohybrid and Medical Textiles (BioTex) AME-Institute of Applied Medical Engineering

   RWTH Aachen University

   Affiliation as printed

   Department of Biohybrid & Medical Textiles (BioTex), AME-Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany

2. Sergio Acosta Aachen Department of Biohybrid and Medical Textiles (BioTex) AME-Institute of Applied Medical Engineering

   RWTH Aachen University

   Affiliation as printed

   Department of Biohybrid & Medical Textiles (BioTex), AME-Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany

3. Stephan Rütten Aachen Electron Microscopy Facility Institute of Pathology

   Universitätsklinikum Aachen · RWTH Aachen University

   Affiliation as printed

   Electron Microscopy Facility, Institute of Pathology, RWTH Aachen University Hospital, Aachen, Germany

4. José Carlos Rodríguez‐Cabello

   Universidad de Valladolid · Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine · Centro de Investigación Biomédica en Red

   Affiliation as printed

   Bioforge Lab, LaDIS, University of Valladolid, CIBER-BBN, Valladolid, Spain

5. Achim Zipse
   Affiliation as printed

   Optimed Medizinische Instrumente GmbH, Ettlingen, Germany

6. Gunter Kerst Aachen Klinik für Kinderkardiologie

   Universitätsklinikum Aachen · RWTH Aachen University

   Affiliation as printed

   Klinik für Kinderkardiologie, RWTH Aachen University Hospital, Aachen, Germany

7. Stefan Jockenhoevel corresponding Aachen Department of Biohybrid and Medical Textiles (BioTex) AME-Institute of Applied Medical Engineering

   RWTH Aachen University

   Affiliation as printed

   Department of Biohybrid & Medical Textiles (BioTex), AME-Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany

8. Alicia Fernández‐Colino corresponding Aachen Department of Biohybrid and Medical Textiles (BioTex) AME-Institute of Applied Medical Engineering

   RWTH Aachen University

   Affiliation as printed

   Department of Biohybrid & Medical Textiles (BioTex), AME-Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany