Standard Guide for in vitro Axial, Bending, Torsional, and Compression Durability Testing of Vascular Stents and Vascular Stent-Grafts

Importancia y uso:

5.1 It is important to consider the durability of implants in deformation modes that are intended to model in vivo conditions. The appropriate amplitude and number of cycles in each of the modes have to be determined independently for the particular clinical use proposed for the implant. These tests do not replicate all varieties and aspects of the deployment process nor the in vivo mechanical environment in its entirety, and as such they cannot be proofs of durability. Instead, the tests provide evidence of durability. The durability tests can also provide a means of assessing design, material, or processing changes.

5.1.1 This guide might be useful for development testing, specification acceptance testing, and regulatory submission testing and filings as it provides a basic assurance that the tests are designed, executed, and reported in a suitable fashion.

5.1.2 If the tests are conducted using a well-defined FTF methodology, they can be useful in:

5.1.2.1 Potential implant improvement through identification of better and worse geometries, materials, and manufacturing processes;

5.1.2.2 Understanding implant durability by estimating the effects of changes in geometry, materials, or manufacturing processes;

5.1.2.3 Estimating the safety factor relative to the amplitudes and other factors in use conditions; and

5.1.2.4 Validating finite element analysis (FEA) and fatigue life models.

5.1.3 As stated in the scope, this guide is not intended to provide the in vivo physiologic deformation conditions to which an implant can be subjected. Reliable clinical data characterizing cyclic in vivo deformation may be lacking for some indications. The user should develop and justify the boundary conditions (e.g., by literature review, in vivo studies, cadaver studies, or modeling of implant in vivo interaction) for the chosen durability bench tests. Additional conditions that may be considered include vessel calcification, vessel taper, eccentric lesions, deformation excursions (e.g., exercise), and vessel remodeling.

5.1.4 Test methods other than those provided in the annexes of this document might be appropriate, depending upon implant design. However, these methods are beyond the scope of this guide.

Subcomité:

F04.30

Referida por:

F3374-19, F3036-21, F3211-17R25, F1877-24

Volúmen:

13.02

Número ICS:

11.040.40 (Implants for surgery, prothetics and orthotics)

Palabras clave:

axial fatigue; bending fatigue; compression fatigue; coronary stent; durability test; endovascular cardiology; endovascular graft; endovascular prostheses; fatigue test; interventional cardiology; intravascular device test; peripheral stent; stent durability; stent fatigue; stent-graft; stent test; torsional fatigue; vascular stent;