title: Endothelial-dependent vasomotion in a coronary segment treated by ABSORB everolimus-eluting bioresorbable vascular scaffold system is related to plaque composition at the time of bioresorption of the polymer: indirect finding of vascular reparative therapy?
abstract: OBJECTIVE
  To analyse the vasoreactivity of a coronary segment, previously scaffolded by the ABSORB bioresorbable vascular scaffold (BVS) device, in relationship to its intravascular ultrasound-virtual histology (IVUS-VH) composition and reduction in greyscale echogenicity of the struts. Coronary segments, transiently scaffolded by a polymeric device, may in the long-term recover a normal vasomotor tone. Recovery of a normal endothelial-dependent vasomotion may be enabled by scaffold bioresorption, composition of the underlying tissue, or a combination of both mechanisms.
  
  
  RESULTS
  All patients from the ABSORB Cohort A and B trials, who underwent a vasomotion test and IVUS-VH investigation at 12 and 24 months, were included. Acetylcholine (Ach) and nitroglycerin were used to test either the endothelial-dependent or -independent vasomotion of the treated segment. Changes in polymeric strut echogenicity-a surrogate for bioresorption-IVUS-VH composition of the tissue underneath the scaffold and their relationship with the pharmacologically induced vasomotion were all evaluated. Overall, 26 patients underwent the vasomotion test (18 at 12 and 8 at 24 months). Vasodilatory response to Ach was quantitatively associated with larger reductions over time in polymeric strut echogenicity (y= -0.159x- 6.85; r= -0.781, P< 0.001). Scaffolded segments with vasoconstriction to Ach had larger vessel areas (14.37 ± 2.50 vs. 11.85 ± 2.54 mm(2), P= 0.030), larger plaque burden (57.31 ± 5.96 vs. 49.09 ± 9.10%, P= 0.018), and larger necrotic core (NC) areas [1.39 (+1.14, +1.74) vs. 0.78 mm(2) (+0.20, +0.98), P= 0.006] compared with those with vasodilation.
  
  
  CONCLUSIONS
  Vasodilatory response to Ach, in coronary segments scaffolded by the ABSORB BVS device, is associated with a reduction in echogenicity of the scaffold over time, and a low amount of NC. In particular, the latter finding resembles the behaviour of a native coronary artery not caged by an intracoronary device.
authors.affiliation: Interventional Cardiology Department, Thoraxcenter, Erasmus MC, 's Gravendijkwal 230, Rotterdam, The Netherlands.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Brugaletta
authors.forename: Jung Ho
authors.initials: JH
authors.lastname: Heo
authors.forename: Hector M
authors.initials: HM
authors.lastname: Garcia-Garcia
authors.forename: Vasim
authors.initials: V
authors.lastname: Farooq
authors.forename: Robert Jan
authors.initials: RJ
authors.lastname: van Geuns
authors.forename: Bernard
authors.initials: B
authors.lastname: de Bruyne
authors.forename: Dariusz
authors.initials: D
authors.lastname: Dudek
authors.forename: Pieter C
authors.initials: PC
authors.lastname: Smits
authors.forename: Jacques
authors.initials: J
authors.lastname: Koolen
authors.forename: Dougal
authors.initials: D
authors.lastname: McClean
authors.forename: Cecile
authors.initials: C
authors.lastname: Dorange
authors.forename: Susan
authors.initials: S
authors.lastname: Veldhof
authors.forename: Richard
authors.initials: R
authors.lastname: Rapoza
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Onuma
authors.forename: Nico
authors.initials: N
authors.lastname: Bruining
authors.forename: John A
authors.initials: JA
authors.lastname: Ormiston
authors.forename: Patrick W
authors.initials: PW
authors.lastname: Serruys
mesh_terms: D020341:Absorbable Implants; D000109:Acetylcholine / Q000494:pharmacology; D000368:Aged; D003331:Coronary Vessels / Q000473:pathology / Q000503:physiopathology*; D054855:Drug-Eluting Stents; D004730:Endothelium, Vascular / Q000473:pathology / Q000503:physiopathology; D000068338:Everolimus; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000188:drug therapy / Q000473:pathology* / Q000503:physiopathology; D005996:Nitroglycerin / Q000494:pharmacology; D058226:Plaque, Atherosclerotic / Q000473:pathology* / Q000503:physiopathology; D020123:Sirolimus / Q000008:administration & dosage / Q000031:analogs & derivatives*; D054457:Tissue Scaffolds; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents / Q000494:pharmacology; D014666:Vasomotor System / Q000187:drug effects
chemical_list: D007166:Immunosuppressive Agents; D014665:Vasodilator Agents; D000068338:Everolimus; D005996:Nitroglycerin; D000109:Acetylcholine; D020123:Sirolimus