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

Carrie E. Herbert, Surendranath Veeram Reddy, Tré R. Welch, Jian Wang, James A. Richardson, Joseph M. Forbess, Alan W. Nugent

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Background: Metallic endovascular stents are utilized off-label in congenital heart disease. Biodegradable stents (BDS) offer potential advantages in a growing child. We have previously reported double opposed helical (DH) BDS up to 6 mm diameter (DH-6). The objectives are to investigate the bench characteristics of larger 8 mm diameter BDS (DH-8) manufactured with increasing strut thicknesses and the inflammatory profile in a porcine model. Methods: DH-8 were manufactured with strut thicknesses 0.10, 0.12, and 0.18 mm and mechanical testing performed. Stents were deployed into the infrarenal descending aorta (DAO) of nine minipigs. At insertion (nonsurvival=2), 1 week (n=2), 1 month (n=2), and 9 months (n=3) follow-up angiography, intravascular ultrasound and histopathology were performed. Results: There was superior recoil and collapse pressure with increasing strut thickness, with 0.18 mm having 1.0% elastic recoil and collapse pressure 0.75 Atmospheres. There was good wall apposition at insertion with 5 BDS (4 DH-8 and 1 DH-6) but suboptimal in 4 as the minipigs infrarenal DAO were >8 mm (deployed at iliac bifurcation). Structural integrity was maintained in 8 BDS with 1 DH-8 collapsed at 9 months, secondary to strut damage at insertion. No thrombosis was seen. There was mild inflammation and neointimal proliferation at 1 week and 1 month, but a moderate inflammatory response at 9 months. Conclusions: DH-8 with increased strut thickness had acceptable mechanical properties at the cost of an increased inflammatory response. Miniaturization to improve delivery and further investigation on the long-term inflammatory profile of thicker struts, including through degradation, is needed.

Original languageEnglish (US)
JournalCatheterization and Cardiovascular Interventions
DOIs
StateAccepted/In press - 2016

Fingerprint

Stents
Miniature Swine
Thoracic Aorta
Miniaturization
Pressure
Atmosphere
Heart Diseases
Angiography
Thrombosis
Swine
Inflammation

Keywords

  • Bioabsorbable
  • Bioabsorbable devices/polymers
  • BIOD
  • SBIO
  • SDES
  • Stent
  • Stent design/structure/coatings

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine
  • Radiology Nuclear Medicine and imaging

Cite this

@article{e8787badab0449aeabba2df203ea5cc6,
title = "Bench and initial preclinical results of a novel 8 mm diameter double opposed helical biodegradable stent",
abstract = "Background: Metallic endovascular stents are utilized off-label in congenital heart disease. Biodegradable stents (BDS) offer potential advantages in a growing child. We have previously reported double opposed helical (DH) BDS up to 6 mm diameter (DH-6). The objectives are to investigate the bench characteristics of larger 8 mm diameter BDS (DH-8) manufactured with increasing strut thicknesses and the inflammatory profile in a porcine model. Methods: DH-8 were manufactured with strut thicknesses 0.10, 0.12, and 0.18 mm and mechanical testing performed. Stents were deployed into the infrarenal descending aorta (DAO) of nine minipigs. At insertion (nonsurvival=2), 1 week (n=2), 1 month (n=2), and 9 months (n=3) follow-up angiography, intravascular ultrasound and histopathology were performed. Results: There was superior recoil and collapse pressure with increasing strut thickness, with 0.18 mm having 1.0{\%} elastic recoil and collapse pressure 0.75 Atmospheres. There was good wall apposition at insertion with 5 BDS (4 DH-8 and 1 DH-6) but suboptimal in 4 as the minipigs infrarenal DAO were >8 mm (deployed at iliac bifurcation). Structural integrity was maintained in 8 BDS with 1 DH-8 collapsed at 9 months, secondary to strut damage at insertion. No thrombosis was seen. There was mild inflammation and neointimal proliferation at 1 week and 1 month, but a moderate inflammatory response at 9 months. Conclusions: DH-8 with increased strut thickness had acceptable mechanical properties at the cost of an increased inflammatory response. Miniaturization to improve delivery and further investigation on the long-term inflammatory profile of thicker struts, including through degradation, is needed.",
keywords = "Bioabsorbable, Bioabsorbable devices/polymers, BIOD, SBIO, SDES, Stent, Stent design/structure/coatings",
author = "Herbert, {Carrie E.} and {Veeram Reddy}, Surendranath and Welch, {Tr{\'e} R.} and Jian Wang and Richardson, {James A.} and Forbess, {Joseph M.} and Nugent, {Alan W.}",
year = "2016",
doi = "10.1002/ccd.26647",
language = "English (US)",
journal = "Catheterization and Cardiovascular Interventions",
issn = "1522-1946",
publisher = "Wiley-Liss Inc.",

}

TY - JOUR

T1 - Bench and initial preclinical results of a novel 8 mm diameter double opposed helical biodegradable stent

AU - Herbert, Carrie E.

AU - Veeram Reddy, Surendranath

AU - Welch, Tré R.

AU - Wang, Jian

AU - Richardson, James A.

AU - Forbess, Joseph M.

AU - Nugent, Alan W.

PY - 2016

Y1 - 2016

N2 - Background: Metallic endovascular stents are utilized off-label in congenital heart disease. Biodegradable stents (BDS) offer potential advantages in a growing child. We have previously reported double opposed helical (DH) BDS up to 6 mm diameter (DH-6). The objectives are to investigate the bench characteristics of larger 8 mm diameter BDS (DH-8) manufactured with increasing strut thicknesses and the inflammatory profile in a porcine model. Methods: DH-8 were manufactured with strut thicknesses 0.10, 0.12, and 0.18 mm and mechanical testing performed. Stents were deployed into the infrarenal descending aorta (DAO) of nine minipigs. At insertion (nonsurvival=2), 1 week (n=2), 1 month (n=2), and 9 months (n=3) follow-up angiography, intravascular ultrasound and histopathology were performed. Results: There was superior recoil and collapse pressure with increasing strut thickness, with 0.18 mm having 1.0% elastic recoil and collapse pressure 0.75 Atmospheres. There was good wall apposition at insertion with 5 BDS (4 DH-8 and 1 DH-6) but suboptimal in 4 as the minipigs infrarenal DAO were >8 mm (deployed at iliac bifurcation). Structural integrity was maintained in 8 BDS with 1 DH-8 collapsed at 9 months, secondary to strut damage at insertion. No thrombosis was seen. There was mild inflammation and neointimal proliferation at 1 week and 1 month, but a moderate inflammatory response at 9 months. Conclusions: DH-8 with increased strut thickness had acceptable mechanical properties at the cost of an increased inflammatory response. Miniaturization to improve delivery and further investigation on the long-term inflammatory profile of thicker struts, including through degradation, is needed.

AB - Background: Metallic endovascular stents are utilized off-label in congenital heart disease. Biodegradable stents (BDS) offer potential advantages in a growing child. We have previously reported double opposed helical (DH) BDS up to 6 mm diameter (DH-6). The objectives are to investigate the bench characteristics of larger 8 mm diameter BDS (DH-8) manufactured with increasing strut thicknesses and the inflammatory profile in a porcine model. Methods: DH-8 were manufactured with strut thicknesses 0.10, 0.12, and 0.18 mm and mechanical testing performed. Stents were deployed into the infrarenal descending aorta (DAO) of nine minipigs. At insertion (nonsurvival=2), 1 week (n=2), 1 month (n=2), and 9 months (n=3) follow-up angiography, intravascular ultrasound and histopathology were performed. Results: There was superior recoil and collapse pressure with increasing strut thickness, with 0.18 mm having 1.0% elastic recoil and collapse pressure 0.75 Atmospheres. There was good wall apposition at insertion with 5 BDS (4 DH-8 and 1 DH-6) but suboptimal in 4 as the minipigs infrarenal DAO were >8 mm (deployed at iliac bifurcation). Structural integrity was maintained in 8 BDS with 1 DH-8 collapsed at 9 months, secondary to strut damage at insertion. No thrombosis was seen. There was mild inflammation and neointimal proliferation at 1 week and 1 month, but a moderate inflammatory response at 9 months. Conclusions: DH-8 with increased strut thickness had acceptable mechanical properties at the cost of an increased inflammatory response. Miniaturization to improve delivery and further investigation on the long-term inflammatory profile of thicker struts, including through degradation, is needed.

KW - Bioabsorbable

KW - Bioabsorbable devices/polymers

KW - BIOD

KW - SBIO

KW - SDES

KW - Stent

KW - Stent design/structure/coatings

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U2 - 10.1002/ccd.26647

DO - 10.1002/ccd.26647

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JF - Catheterization and Cardiovascular Interventions

SN - 1522-1946

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