Braided composite stent for peripheral vascular applications

Abstract

Braided composite stent (BCS), woven with nitinol wires and polyethylene terephthalate (PET) strips, provides a hybrid design of stent. The mechanical performance of this novel stent has not been fully investigated yet. In this work, the influence of five main design factors (number of nitinol wires, braiding angle, diameter of nitinol wire, thickness and stiffness of the PET strip) on the surface coverage, radial strength, and flexibility of the BCS were systematically studied using computational models. The orthogonal experimental design was adopted to quantitatively analyze the sensitivity of multiple factors using the minimal number of study cases. Results have shown that the nitinol wire diameter and the braiding angle are two most important factors determining the mechanical performance of the BCS. A larger nitinol wire diameter led to a larger radial strength and less flexibility of the BCS. A larger braiding angle could provide a larger radial strength and better flexibility. In addition, the impact of the braiding angle decreased when the stent underwent a large deformation. At the same time, the impact of the PET strips increased due to the interaction with nitinol wires. Moreover, the number of PET strips played an important role in the surface coverage. This study could help understand the mechanical performance of BCS stent and provides guidance on the optimal design of the stent targeting less complications.

Off-label use of interwoven carotid stent in common femoral artery occlusion after surgery

“…An analysis of the biomechanical properties of this stent type showed that the angle between the wires is essential for maintaining its flexibility. 7 Moreover, compared with other interwoven stents in an experimental model of a stenotic rigid vessel, the Roadsaver stent demonstrated a lower reaction force on the vessel wall at the point of maximum stenosis. 8 This could lead to a minor propensity to neointimal hyperplasia formation.…”

A biodegradable polymer stent with high radial performance: Potential for treatment of portal vein stenosis

“…[21][22][23] However, the weaker radial support performance compared with metal stent has limited its development in PVS therapy. To enhance the radial force of biodegradable polymer stents, researchers have systematically studied the impact of structural parameters on radial force, such as the braid angle β, 24,25 constraint mode, 26 knitting needle count N, 27 the diameter of the monofilament d, 28 and the outer diameter of the stent D. [29][30][31] For example, as the braid angle increases, the structure becomes looser, the interaction between the monofilaments decreases, and the radial force of the stent diminishes. More stent designs have been developed to further improve mechanical properties.…”

Load-sharing characteristics of stenting and post-dilation in heavily calcified coronary artery

“…The Finite element (FE) method has been widely used to evaluate stent behaviors [27][28][29] and predict vessel damage and adaptations [12][13][14][15][16][17]. Speci cally, three-dimensional patient-speci c artery models have been developed by coregistrating both optical coherence tomography (OCT) and computerized tomography (CT) images for performing structural and hemodynamic analyses [30].…”