Membrane degradation of covered stents in the upper gastrointestinal tract: frequency and clinical significance

J Vasc Interv Radiol. 2008 Feb;19(2 Pt 1):220-4. doi: 10.1016/j.jvir.2007.09.023.


Purpose: To evaluate the frequency, clinical significance, and predictive factors of membrane degradation of covered stents in the upper gastrointestinal (UGI) tract.

Materials and methods: From 1996 to 2006, 166 stents were removed from 151 patients. Indications for stent removal included temporary stent placement for esophageal cancer before radiation therapy or radiation-chemotherapy (n = 53), stent migration (n = 40), temporary stent placement for a benign UGI stricture (n = 32), pain (n = 21), recurrent obstruction (n = 16), incomplete stent expansion (n = 1), recurrent transesophageal fistula (n = 2), and aspiration (n = 1). Removed stents were examined to evaluate possible causes of membrane degradation. Multivariate analysis was performed to determine the predictive factors of membrane degradation.

Results: Degradation of the covering membrane occurred in 14 of the 166 stents (8%). Recurrent obstruction due to tumor ingrowth (n = 7) and reopening of the transesophageal fistula (n = 1) through the degraded membrane occurred in eight stents (5%). At multivariate logistic regression analysis, the type of covering membrane (P = .018), stricture location (P = .006), and duration of stent placement (P = .002) were significantly associated with degradation of the covering membrane.

Conclusions: Degradation of the covering membrane after stent placement in the UGI tract is not an uncommon event, and recurrent obstruction or fistula can occur through the degraded membrane. A polyurethane membrane is not biostable and dissolves over time, particularly in the gastroduodenal area.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Alloys
  • Constriction, Pathologic
  • Device Removal
  • Female
  • Gastrointestinal Diseases / pathology
  • Gastrointestinal Diseases / therapy*
  • Humans
  • Logistic Models
  • Male
  • Middle Aged
  • Polytetrafluoroethylene
  • Prospective Studies
  • Prosthesis Failure
  • Stents*
  • Upper Gastrointestinal Tract*


  • Alloys
  • nitinol
  • Polytetrafluoroethylene