title: Stent graft composition plays a material role in the postimplantation syndrome.
abstract: OBJECTIVE
  In patients undergoing endovascular aneurysm repair (EVAR), the postimplantation syndrome (PIS), comprising fever and inflammation, occurs frequently. The cause of PIS is unclear, but graft composition and acute thrombus formation may play a role. The objective of this study was to evaluate these possible causes of the inflammatory response after EVAR.
  
  
  METHODS
  One hundred forty-nine patients undergoing elective EVAR were included. Implanted stent grafts differed mainly in the type of fabric used: either woven polyester (n=82) or expanded polytetrafluorethylene (ePTFE; n=67). Tympanic temperature and C-reactive protein (CRP) were assessed daily during hospitalization. PIS was defined as the composite of a body temperature of ≥38°C coinciding with CRP>10 mg/L. Besides graft composition, the size of the grafts and the volume of new-onset thrombus were calculated using dedicated software, and results were correlated to PIS.
  
  
  RESULTS
  Implantation of grafts made of polyester was associated with higher postoperative temperature (P<.001), CRP levels (P<.001), and incidence of PIS (56.1% vs 17.9%; P<.001) compared to ePFTE. After multivariate analysis, woven polyester stent grafts were independently associated with an increased risk of PIS (hazard ratio, 5.6; 95% confidence interval, 1.6-19.4; P=.007). Demographics, amount of graft material implanted, or new-onset thrombus had no association with PIS.
  
  
  CONCLUSIONS
  The composition of stent grafts may play a material role in the incidence of postimplantation syndrome in patients undergoing EVAR. Implantation of stent grafts based on woven polyester was independently associated with a stronger inflammatory response.
authors.affiliation: Department of Anesthesiology, Erasmus University Medical Centre, Rotterdam, The Netherlands.
authors.forename: Michiel T
authors.initials: MT
authors.lastname: Voûte
authors.forename: Frederico M
authors.initials: FM
authors.lastname: Bastos Gonçalves
authors.forename: Koen M
authors.initials: KM
authors.lastname: van de Luijtgaarden
authors.forename: Casper G A
authors.initials: CG
authors.lastname: Klein Nulent
authors.forename: Sanne E
authors.initials: SE
authors.lastname: Hoeks
authors.forename: Robert Jan
authors.initials: RJ
authors.lastname: Stolker
authors.forename: Hence J M
authors.initials: HJ
authors.lastname: Verhagen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000150:complications / Q000473:pathology / Q000601:surgery*; D001807:Blood Vessel Prosthesis / Q000009:adverse effects*; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects*; D001831:Body Temperature; D002097:C-Reactive Protein / Q000378:metabolism; D057510:Endovascular Procedures / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D011091:Polyesters; D011138:Polytetrafluoroethylene; D011474:Prosthesis Design / Q000009:adverse effects*; D012189:Retrospective Studies; D015607:Stents / Q000009:adverse effects*; D013577:Syndrome
chemical_list: D011091:Polyesters; D011138:Polytetrafluoroethylene; D002097:C-Reactive Protein