title: Mechanical and microstructural analysis of a radially expandable vascular conduit for neonatal and pediatric cardiovascular surgery.
abstract: In pediatric cardiovascular surgery, there is a significant need for vascular prostheses that have the potential to grow with the patient following implantation. Current clinical options consist of nonexpanding conduits, requiring repeat surgeries as the patient outgrows the device. To address this issue, PECA Labs has developed a novel ePTFE vascular conduit with the capability of being radially expanded via balloon catheterization. In the described study, a systematic characterization and comparison of two proprietary ePTFE expandable conduits was conducted. Conduit sizes of 8 and 16 mm inner diameters for both conduits were evaluated before and after expansion with a 26 mm balloon. Comprehensive mechanical testing was completed, including quantification of circumferential, and longitudinal tensile strength, suture retention strength, burst strength, water entry pressure, dynamic compliance, and kink radius. Scanning electron microscopy was used to investigate the microstructural properties. Automated extraction of the fiber architectural features for each scanning electron micrograph was achieved with an algorithm for each conduit before and after expansion. Results showed that both conduits were able to expand significantly, to as much as 2.5× their original inner diameter. All mechanical properties were within clinically acceptable values following expansion. Analysis of the microstructure properties of the conduits revealed that the circumferential main angle of orientation, orientation index, and spatial periodicity did not significantly change following expansion, whereas the node area fraction decreased post expansion. Successful proof-of-concept of this novel product represents a critical step toward clinical translation and provides hope for newborns and growing children with congenital heart disease. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 659-671, 2018.
authors.affiliation: Department of Bioengineering, University of Pittsburgh, Pittsburgh, Penninsylvania.
authors.forename: Abigail E
authors.initials: AE
authors.lastname: Loneker
authors.affiliation: Department of Bioengineering, University of Pittsburgh, Pittsburgh, Penninsylvania.|McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Penninsylvania.
authors.forename: Samuel K
authors.initials: SK
authors.lastname: Luketich
authors.affiliation: PECA Labs, Pittsburgh, Penninsylvania, 15224.
authors.forename: Doug
authors.initials: D
authors.lastname: Bernstein
authors.affiliation: PECA Labs, Pittsburgh, Penninsylvania, 15224.
authors.forename: Arush
authors.initials: A
authors.lastname: Kalra
authors.affiliation: University of Texas Southwestern Medical Center, Dallas, Texas.
authors.forename: Alan W
authors.initials: AW
authors.lastname: Nugent
authors.affiliation: Department of Bioengineering, University of Pittsburgh, Pittsburgh, Penninsylvania.|McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Penninsylvania.|Department of Surgery, University of Pittsburgh, Pittsburgh, Penninsylvania.|School of Medicine, University of Pittsburgh, Pittsburgh, Penninsylvania.|RiMED Foundation, Palermo, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: D'Amore
authors.affiliation: PECA Labs, Pittsburgh, Penninsylvania, 15224.
authors.forename: Denver M
authors.initials: DM
authors.lastname: Faulk
mesh_terms: D001807:Blood Vessel Prosthesis; D006328:Cardiac Catheterization; D062906:Cardiac Catheters; D013504:Cardiovascular Surgical Procedures; D002648:Child; D006331:Heart Diseases / Q000151:congenital* / Q000601:surgery*; D006801:Humans; D007231:Infant, Newborn; D011138:Polytetrafluoroethylene / Q000737:chemistry*; D011474:Prosthesis Design; D060489:Prosthesis Retention; D013718:Tensile Strength; D014652:Vascular Diseases / Q000151:congenital / Q000601:surgery*
chemical_list: D011138:Polytetrafluoroethylene
keywords: cardiovascular; ePTFE; pediatric surgery; vascular conduit; vascular graft