title: Expansion of the Multi-Link Frontier™ coronary bifurcation stent: micro-computed tomographic assessment in human autopsy and porcine heart samples.
abstract: BACKGROUND
  Treatment of coronary bifurcation lesions remains challenging, beyond the introduction of drug eluting stents. Dedicated stent systems are available to improve the technical approach to the treatment of these lesions. However dedicated stent systems have so far not reduced the incidence of stent restenosis. The aim of this study was to assess the expansion of the Multi-Link (ML) Frontier™ stent in human and porcine coronary arteries to provide the cardiologist with useful in-vitro information for stent implantation and selection.
  
  
  RESULTS
  Nine ML Frontier™ stents were implanted in seven human autopsy heart samples with known coronary artery disease and five ML Frontier™ stents were implanted in five porcine hearts. Proximal, distal and side branch diameters (PD, DD, SBD, respectively), corresponding opening areas (PA, DA, SBA) and the mean stent length (L) were assessed by micro-computed tomography (micro-CT). PD and PA were significantly smaller in human autopsy heart samples than in porcine heart samples (3.54±0.47 mm vs. 4.04±0.22 mm, p = 0.048; 10.00±2.42 mm(2) vs. 12.84±1.38 mm(2), p = 0.034, respectively) and than those given by the manufacturer (3.54±0.47 mm vs. 4.03 mm, p = 0.014). L was smaller in human autopsy heart samples than in porcine heart samples, although data did not reach significance (16.66±1.30 mm vs. 17.30±0.51 mm, p = 0.32), and significantly smaller than that given by the manufacturer (16.66±1.30 mm vs. 18 mm, p = 0.015).
  
  
  CONCLUSIONS
  Micro-CT is a feasible tool for exact surveying of dedicated stent systems and could make a contribution to the development of these devices. The proximal diameter and proximal area of the stent system were considerably smaller in human autopsy heart samples than in porcine heart samples and than those given by the manufacturer. Special consideration should be given to the stent deployment procedure (and to the follow-up) of dedicated stent systems, considering final intravascular ultrasound or optical coherence tomography to visualize (and if necessary optimize) stent expansion.
authors.affiliation: I. Department of Medicine, Faculty of Medicine Mannheim, University of Heidelberg, Mannheim, Germany. stefan.kralev@umm.de
authors.forename: Stefan
authors.initials: S
authors.lastname: Kralev
authors.forename: Benjamin
authors.initials: B
authors.lastname: Haag
authors.forename: Jens
authors.initials: J
authors.lastname: Spannenberger
authors.forename: Siegfried
authors.initials: S
authors.lastname: Lang
authors.forename: Marc A
authors.initials: MA
authors.lastname: Brockmann
authors.forename: Soenke
authors.initials: S
authors.lastname: Bartling
authors.forename: Alexander
authors.initials: A
authors.lastname: Marx
authors.forename: Karl-Konstantin
authors.initials: KK
authors.lastname: Haase
authors.forename: Martin
authors.initials: M
authors.lastname: Borggrefe
authors.forename: Tim
authors.initials: T
authors.lastname: Süselbeck
mesh_terms: D000818:Animals; D001344:Autopsy; D019917:Blood Vessel Prosthesis Implantation / Q000295:instrumentation*; D023903:Coronary Restenosis / Q000517:prevention & control; D023921:Coronary Stenosis / Q000000981:diagnostic imaging / Q000628:therapy*; D005240:Feasibility Studies; D006801:Humans; D015607:Stents; D013552:Swine; D014057:Tomography, X-Ray Computed