The mechanical behavior and biocompatibility of polymer blends for Patent Ductus Arteriosus (PDA) occlusion device.
Patent Ductus Arteriosus (PDA) is a cardiovascular defect that occurs in 1 out of every 2000 births, and if left untreated, may lead to severe cardiovascular problems. Current options for occluding utilize meta scaffolds with polymer fabric, and are permanent. The purpose of this study was to develop a fully degradable occluder for the closure of PDA, that can be deployed percutaneously without open-heart surgery. For percutaneous deployment, both elasticity and sufficient mechanical strength are required of the device components. As this combination of properties is not achievable with currently-available homo- or copolymers, blends of biodegradable poly(ε-caprolactone) (PCL) and poly(L-lactide-co-ε-caprolactone) (PLC) with various compositions were studied as the potential material for the PDA occlusion device. Microstructures of this blend were characterized by differential scanning calorimetry (DSC) and tensile tests. DSC results demonstrated the immiscibility between PCL and its copolymer PLC. Furthermore, the mechanical properties, i.e. elastic modulus and strain recovery, of the blends could be largely tailored by changing the continuous phase component. Based on the thermo-mechanical tests, suitable blends were selected to fabricate a prototype of PDA occluder and its in vitro performance, in term of device recovery (from its sheathed configuration), biodegradation rate and blood compatibility, was evaluated. The current results indicate that the device is able to recover elastically from a sheath within 2-3min for deployment; the device starts to disintegrate within 5-6 months, and the materials have no adverse effects on the platelet and leucocyte components of the blood. Biocompatibility implantation studies of the device showed acceptable tissue response. Finally, an artificial PDA conduit was created in a pig model, and the device deployment was tested from a sheath: the device recovered within 2-3min of unsheathing and fully sealed the conduit, the device remains stable and is completely covered by tissue at 1 month follow up. Thus, a novel prototype for PDA occlusion that is fully degradable has been developed to overcome the limitations of the currently used metal/fabric devices.
School of Materials Science & Engineering, Nanyang Technological University, Singapore 639798, Singapore.
Yingying
Y
Huang
School of Materials Science & Engineering, Nanyang Technological University, Singapore 639798, Singapore.
Yee Shan
YS
Wong
School of Materials Science & Engineering, Nanyang Technological University, Singapore 639798, Singapore.
Jumiati
J
Wu
School of Materials Science & Engineering, Nanyang Technological University, Singapore 639798, Singapore.
Jen Fong
JF
Kong
School of Materials Science & Engineering, Nanyang Technological University, Singapore 639798, Singapore.
Jing Ni
JN
Chan
Insightra Medical Inc., Irvine, CA 92618, USA.
Laxmikant
L
Khanolkar
Apollo Hospital, Secunderabad 500003, India.
Dasari P
DP
Rao
School of Materials Science & Engineering, Nanyang Technological University, Singapore 639798, Singapore.
Freddy Y C
FY
Boey
School of Materials Science & Engineering, Nanyang Technological University, Singapore 639798, Singapore. Electronic address: assubbu@ntu.edu.sg.
Subbu S
SS
Venkatraman
D000818:Animals; D001672:Biocompatible Materials / Q000009:adverse effects / Q000138:chemical synthesis*; D019245:Compressive Strength; D004374:Ductus Arteriosus, Patent / Q000000981:diagnostic imaging / Q000628:therapy*; D055119:Elastic Modulus; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005240:Feasibility Studies; D006244:Hardness; D011091:Polyesters / Q000737:chemistry* / Q000627:therapeutic use; D011817:Rabbits; D011859:Radiography; D055989:Septal Occluder Device; D013718:Tensile Strength; D016896:Treatment Outcome
D001672:Biocompatible Materials; D011091:Polyesters; C016240:polycaprolactone; C062968:lactide-caprolactone copolymer
Biodegradable; Patent ductus arteriosus; Poly(L-lactide-co-ε-caprolactone); Poly(ε-caprolactone)