title: Degradation of tungsten coils implanted into the subclavian artery of New Zealand white rabbits is not associated with local or systemic toxicity.
abstract: OBJECTIVE
  To assess whether corrosion of tungsten coils is related to residual shunting and to evaluate whether elevated tungsten serum levels are associated with local or systemic toxicity.
  
  
  METHODS
  Tungsten coils (SPI, Balt, France) were implanted into the subclavian artery of New Zealand white rabbits leading to a residual high-flow shunt in 5/10 rabbits. Serial serum tungsten levels, complete blood count and clinical chemistry were analysed prior to the implantation as well as 15 min, 2 and 4 months thereafter. After 4 months the rabbits underwent repeat angiography before they were sacrificed and the internal organs were evaluated histopathologically.
  
  
  RESULTS
  Mean tungsten levels rose from 0.48 microg/l prior to the implantation to 12.4 microg/l 4 months post-implantation. The rise in serum tungsten levels was neither associated with residual shunting present at the time of implantation nor with residual shunting at the time of explantation. One animal had to be sacrificed because of non-resolving palsy of the upper extremity. The remaining animals had an uneventful clinical course with no signs of toxicity of the elevated tungsten levels. Histological examination revealed no evidence of local or systemic toxicity of the tungsten coils.
  
  
  CONCLUSIONS
  Tungsten coils corrode and lead to a steady increase in serum tungsten levels starting as early as 15 min after implantation. Residual shunting does not seem to influence the kinetics of corrosion of tungsten coils. Despite markedly elevated serum tungsten levels 4 months after implantation degradation of tungsten coils is not associated with local or systemic toxicity.
authors.affiliation: Department of Pediatric Cardiology and Pediatric Intensive Care, Georg-August University, Robert-Koch-Str. 40, D-37075 Goettingen, Germany. mpeuste@gwdg.de
authors.forename: Matthias
authors.initials: M
authors.lastname: Peuster
authors.forename: Christoph
authors.initials: C
authors.lastname: Fink
authors.forename: Peter
authors.initials: P
authors.lastname: Wohlsein
authors.forename: Michael
authors.initials: M
authors.lastname: Bruegmann
authors.forename: Alexander
authors.initials: A
authors.lastname: Günther
authors.forename: Volker
authors.initials: V
authors.lastname: Kaese
authors.forename: Matthias
authors.initials: M
authors.lastname: Niemeyer
authors.forename: Heinz
authors.initials: H
authors.lastname: Haferkamp
authors.forename: Christian v
authors.initials: Cv
authors.lastname: Schnakenburg
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D004621:Embolization, Therapeutic / Q000295:instrumentation*; D007700:Kinetics; D011817:Rabbits; D013348:Subclavian Artery; D013997:Time Factors; D014414:Tungsten / Q000097:blood / Q000493:pharmacokinetics* / Q000633:toxicity; D017973:Tungsten Compounds / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D017973:Tungsten Compounds; D014414:Tungsten