ePTFE

About the material

  • Expanded polytetrafluoroethylene (ePTFE)
  • Flexible, biocompatible material
  • Lubricity, strength and durability
  • The ability to collapse and expand repeatedly is critical for use in vascular applications
  • The material can cycle many times w/o breaking or coming off of the device - which makes it valuable in the stent deployment process and resistant to wear in the body.
  • Varying permeability
  • Material is easy to work with due to its temperature stability and achievable thinness.
    • Internal and external layers of coating measure in microns - meaning while the structure is deployed, it enhances the ability to navigate the vasculature but does not add significant thickness or diameter to the primary device.

Covering Technologies

Sintering

 

Suturing

  • Takes much longer, is more manual and costs exhorbentently more.
  • Difficult to scale up in a manufacturing operation

 

Electrospinning/Wrapping (?) Difference?

 

Lamination

  • Our ePTFE covering can encapsulate complex geometries and have an extremely thin wall thickness (can be less than 0.001”)
  • Covering technologies
    • Suturing - time consuming, manual, less repetitive, harder to scale up. 1 layer of ePTFE the sutures create another mini layer and generate stress in the areas of the sutures - disadvantage for crimping profile.
    • Lamination - can be laminated on ID, OD, or both. Uses temperature and pressure to connect the cover to the metallic scaffold - sandwich like - good for when thickness increase and crimping profile does not pose a problem
    • Sintering - 2 layers of eptfe are sintered onto each other then adhered to the metal stent - process requires higher temperatures so more of an issue for the thermal propeties of the nitinol or metalic stent

Clinical Areas + Applications

  • Valve Repair & Replacement
  • Left Atrial Appendage (LAA) Implants
  • Mitral Valve Clips
  • Septal Occluders

Covering Testing Standards

We use our company's expertise and experience to manage all aspects of the testing your ePTFE-covered device requires - whether performed in-house or through our partners. Our testing services examine your device's conformity with standards and compatibility with appropriate accessories and fittings.

Medical Murray and it's partners can assist you with the independent testing of your implant ePTFE covering systems against ISO 25529-1:2017 and ISO 7198:2016 requirements.

ISO 25529-1:2017

Cardiovascular implants — Endovascular device requirements

>   Corrosion

>   Fatigue & Durability

>   Fixation & Seal

>   Leakage

>   Migration Resistance

>   Patency

ISO 7198:2016

Tubular vascular grafts and vascular patches testing requirements

>   Permeability

>   Porosity (non-textile materials)

>   Tensile Strength

>   Suture Retention & Burst Strength

>   Kink Diameter / Radius

>   Preclinical In-Vivo