title: Head-to-head comparison of a drug-free early programmed dismantling polylactic acid bioresorbable scaffold and a metallic stent in the porcine coronary artery: six-month angiography and optical coherence tomographic follow-up study.
abstract: BACKGROUND
  We aimed to evaluate a new drug-free fully bioresorbable lactic acid-based scaffold designed to allow early dismantling synchronized with artery wall healing in comparison with a bare metal stent (BMS).
  
  
  RESULTS
  Twenty-three BMS (3.0×12 mm) and 36 lactic acid-based bioresorbable scaffolds (BRS, 3.0×11 mm) were implanted in porcine coronary arteries. QCA and optical coherence tomographic analyses were performed immediately after implantation and repeated after 1, 3, and 6 months. Microcomputed tomography was used to detect scaffold dismantling. Polymer degradation was evaluated throughout the study. The primary end-point was late lumen loss, and the secondary end-points were scaffold/stent diameter and acute recoil. Acute recoil was low and comparable between the BRS and the BMS groups (4.6±6.7 versus 4.6±5.1%; P=0.98). BRS outer diameter increased significantly from 1 to 6 months indicating late positive scaffold remodeling (P<0.0001), whereas BMS diameter remained constant (P=0.159). Late lumen loss decreased significantly from 1 to 6 months in the BRS group (P=0.003) without significant difference between BRS and BMS groups at 6 months (P=0.68). Microcomputed tomography identified BRS dismantling starting at 3 months, and weight-average molar masses of scaffold parts were 20% and 14% of their initial values at 3 and 6 months.
  
  
  CONCLUSIONS
  BRS and BMS have similar 6-month outcomes in porcine coronary arteries. Interestingly, BRS dismantling was detected from 3 months and resulted in late lumen enlargement by increased scaffold diameter at 6 months.
authors.affiliation: From the Cardiology Department, European Georges Pompidou Hospital, Paris Centre de Recherche Cardiovasculaire, INSERM U 970, Université Paris-Descartes, Paris, France (E.D., M.R., A.L.); Faculty of Pharmacy, Institut Charles Gherardt, MACS (T.S.) UMR CNRS 5253 and Faculty of Pharmacy, Research Center for Artificial Biopolymers, Institut de Biomolecules Max Mousseron, University Montpellier 1-CNRS, Montpellier, France (M.V.); AccelLAB Inc, Boisbriand, Quebec, Canada (G.L.); and Arterial Remodeling Technologies, Noisy le Roi, France (M.v.d.L.).
authors.forename: Eric
authors.initials: E
authors.lastname: Durand
authors.forename: Tahmer
authors.initials: T
authors.lastname: Sharkawi
authors.forename: Guy
authors.initials: G
authors.lastname: Leclerc
authors.forename: Marine
authors.initials: M
authors.lastname: Raveleau
authors.forename: Machiel
authors.initials: M
authors.lastname: van der Leest
authors.forename: Michel
authors.initials: M
authors.lastname: Vert
authors.forename: Antoine
authors.initials: A
authors.lastname: Lafont
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D017023:Coronary Angiography; D003331:Coronary Vessels / Q000601:surgery*; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry; D008670:Metals / Q000737:chemistry; D023421:Models, Animal; D011091:Polyesters; D011108:Polymers / Q000737:chemistry; D019919:Prosthesis Implantation; D015607:Stents / Q000706:statistics & numerical data*; D013552:Swine; D013997:Time Factors; D054457:Tissue Scaffolds / Q000737:chemistry / Q000706:statistics & numerical data*; D041623:Tomography, Optical Coherence
chemical_list: D001672:Biocompatible Materials; D008670:Metals; D011091:Polyesters; D011108:Polymers; D019344:Lactic Acid; C033616:poly(lactide)
keywords: bioabsorbable implants; coronary restenosis; polymers; stent