Stent-Graft Fabrics Incorporating a Specific Corona Ready to Fenestrate

Area of Science:

• Biomaterials Engineering
• Vascular Surgery
• Medical Device Design

Background:

• In situ fenestration of endovascular stent-grafts is crucial for treating complex aneurysms.
• Fabric tearing during fenestration can lead to endoleaks and device failure.
• Existing stent-graft materials are susceptible to tearing from balloon angioplasty and physiological motion.

Purpose of the Study:

• To design and evaluate a novel stent-graft fabric with a corona structure to prevent tearing.
• To assess the fabric's suitability for laser fenestration and its resistance to tearing.
• To compare the novel fabric design against commercial stent-graft devices.

Main Methods:

• A new fabric design featuring a corona surrounding a central cluster with varying weave structures (plain, twill, honeycomb) was created.
• Specimens were characterized for morphology, thickness, and water permeability.
• In situ fenestrations were performed using Excimer laser and balloon angioplasty, followed by microscopy analysis.

Main Results:

• All tested fabrics, including the novel design, met low-profile and low-permeability requirements.
• Fenestrated apertures were smaller than the angioplasty balloon diameter.
• Tearing was successfully confined within the corona, preventing extension into the main graft fabric.

Conclusions:

• The novel corona design effectively contains fabric tearing during fenestration and post-implantation motion.
• This design shows promise for improving stent-graft durability and reducing endoleak incidence.
• Further bench and animal studies are warranted to assess clinical applicability.