title: Incidence and predictors of drug-eluting stent fracture in human coronary artery a pathologic analysis.
abstract: OBJECTIVE
  The aim of this study was to perform pathologic assessment on stent fracture.
  
  
  BACKGROUND
  Clinically, stent fracture has been reported in 1% to 2% of patients after drug-eluting stent (DES) implantation.
  
  
  METHODS
  High-contrast film-based radiographs of 177 consecutive lesions from the CVPath DES autopsy registry were reviewed. Stent fracture was graded as I (single-strut fracture), II (> or =2 struts), III (> or =2 struts with deformation), IV (with transection without gap), and V (with transection causing gap in stent segment). The incidence of adverse pathologic findings (thrombosis and restenosis) was assessed histologically.
  
  
  RESULTS
  Stent fracture was documented in 51 lesions (29%; grade I = 10, II = 14, III = 12, IV = 6, and V = 9). Lesions with stent fracture had longer duration after implantation (172 days [interquartile range (IQR) 31 to 630 days] vs. 44 days [IQR 7 to 270 days], p = 0.004), a higher rate of Cypher (Cordis Corp., Miami Lakes, Florida) stent usage (63% vs. 36%, p = 0.001), longer stent length (30.0 mm [IQR 22.0 to 40.0 mm] vs. 20.0 mm [IQR 14.0 to 27.3 mm], p < 0.0001), and a higher rate of overlapping stents (45% vs. 22%, p = 0.003). Although fracture with grade I to IV did not have significant impact on the occurrence of adverse pathologic findings such as thrombosis and restenosis, 67% of the grade V fracture lesions were associated with adverse pathologic findings at fracture sites. Longer stent length, use of Cypher, and longer duration of implant were identified as independent risk factors of stent fracture by logistic regression analysis.
  
  
  CONCLUSIONS
  The incidence of stent fracture was 29% lesions at autopsy, which is much higher than clinically reported. A high rate of adverse pathologic findings was observed in lesions with grade V stent fracture, whereas fracture with grade I to IV did not have a significant impact on the pathological outcome.
authors.affiliation: CVPath Institute, Inc., Gaithersburg, Maryland, USA.
authors.forename: Gaku
authors.initials: G
authors.lastname: Nakazawa
authors.forename: Aloke V
authors.initials: AV
authors.lastname: Finn
authors.forename: Marc
authors.initials: M
authors.lastname: Vorpahl
authors.forename: Elena
authors.initials: E
authors.lastname: Ladich
authors.forename: Robert
authors.initials: R
authors.lastname: Kutys
authors.forename: Isidora
authors.initials: I
authors.lastname: Balazs
authors.forename: Frank D
authors.initials: FD
authors.lastname: Kolodgie
authors.forename: Renu
authors.initials: R
authors.lastname: Virmani
mesh_terms: D001344:Autopsy; D023921:Coronary Stenosis / Q000175:diagnosis / Q000601:surgery*; D003331:Coronary Vessels / Q000473:pathology*; D054855:Drug-Eluting Stents; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology* / Q000473:pathology; D011379:Prognosis; D011475:Prosthesis Failure; D014481:United States / Q000453:epidemiology