Bioresorbable Stent to Manage Congenital Heart Defects in Children

Area of Science:

• Biomaterials Science
• Pediatric Cardiology
• Medical Device Engineering

Background:

• Pediatric intravascular stents face challenges with degradation and vessel growth inhibition.
• Current metal stents can impede natural vessel development in children.
• Need for bioresorbable alternatives that support vascular growth.

Purpose of the Study:

• To develop and characterize large-diameter poly(L-lactide) stents (DH-BDS) for pediatric use.
• To evaluate the mechanical properties, degradation kinetics, and suitability of DH-BDS stents compared to metal controls.
• To assess DH-BDS as a potential alternative to current pediatric interventional strategies.

Main Methods:

• Poly(L-lactide) fibers (250 μm and 300 μm) were fabricated into pediatric-sized stents (Ø10-20 mm).
• Mechanical and thermal characterization of fibers and stents.
• Comparison of stent radial strength to metal stents; mass loss and degradation modeling for time-to-degradation estimation.

Main Results:

• Thicker DH-BDS fibers showed lower stiffness and yield stress but similar fail strength at higher strains.
• Stent crystallinity and glass transition temperatures were suitable for physiological conditions.
• DH-BDS stents demonstrated radial strength comparable to metal stents across various diameters, with minimal degradation and strength loss in the first year.
• Degradation modeling predicted complete stent disappearance within 2.8–4.5 years.

Conclusions:

• DH-BDS stents exhibit mechanical properties suitable for pediatric applications, matching metal stent hoop strength.
• These bioresorbable stents show minimal degradation in the first year and are predicted to fully degrade within 4.5 years.
• DH-BDS represents a promising, degradable alternative to current intravascular stenting methods in pediatric interventions.