Novel Bioresorbable Stent Design and Fabrication: Congenital Heart Disease Applications

Bench and initial preclinical results of a novel 8 mm diameter double opposed helical biodegradable stent

“…Bench testing and preclinical results up to 6 mm diameter (DH‐6) are reported. The strut thickness of these 3–6 mm DH BDS was 0.10 mm and as expected, the recoil and collapse pressure declined with increasing diameter . The aims of this study are to manufacture larger 8 mm diameter BDS (DH‐8) applicable for CHD with increasing strut thicknesses, document the bench characteristics and investigate the inflammatory profile at 1‐week, 1‐ and 9‐ months follow‐up in a porcine model.…”

“…DH‐8 BDS were designed and fabricated as previously described . Briefly, commercially available PLLA‐32 with a molecular weight of 565 kD (Corbion, Amsterdam, Netherlands) was used.…”

“…Stent crimping was performed with a manual crimp tool (Model RJ25, Blockwise Engineering, Chicago, IL). A standard stent expansion and relaxation protocol was used , expanding the balloon in a submerged water bath at 37°C in 1 Atmosphere (ATM)/5 s steps from 0 to 8 ATM and back in 1 ATM steps to 0 ATM. A Nikon D70 camera with Sigma 50 mm DG Macro D Lens recorded stent expansion and stent fiber deformation at an orthogonal position to the axial view of the stent.…”

“…The stent collapse pressure test was performed using a pressure chamber previously described . Briefly, the stent was wrapped in a plastic sheath and placed in a sealed transparent acrylic chamber.…”

A novel biodegradable stent applicable for use in congenital heart disease: Bench testing and feasibility results in a rabbit model

“…The elastic recoil is lower for the smaller DH stents: DH‐3 (0.48% ± 0.07%, P < 0.05) and DH‐4 (0.46% ± 0.1%, P < 0.05) when compared to the DH‐5 (1.6% ± 0.08%), and DH‐6 (1.43% ± 0.14%) stents. The collapse pressure was inversely related to stent diameter and ranged upwards from a low of 0.63 ± 0.02 ATM (DH‐6) to 0.72 ± 0.02 ATM (DH‐5), 0.80 ± 0.01 ATM (DH‐4), and 1.07 ± 0.02 ATM for the DH‐3 stent . The collapse pressure is reduced with larger diameter stents and requires less work to expand the stent.…”