title: The natural history of parallel transjugular intrahepatic portosystemic stent shunts using uncovered stent: the role of host-related factors.
abstract: OBJECTIVE
  Parallel shunts (PS) are used in the management of transjugular intrahepatic portosystemic stent-shunt (TIPS) insufficiency, a major limitation of the technique. This study describes the natural history of PS, and uses them as a model to assess the role of host factors in the development of primary shunt insufficiency.
  
  
  METHODS
  Out of 338 patients with TIPS, 40 (11.8%) patients required insertion of a PS. Baseline and follow-up data of these patients were collected. Regular shunt surveillance involved biannual clinic visits and transjugular portography.
  
  
  RESULTS
  The non-PS group (group 1; n = 298) and the PS group (group 2; n = 40) had similar baseline demographic and disease characteristics. Index shunts of both groups and the PS produced a significant portal pressure gradient drop (P < 0.001), which was less in the index shunts of Group 2 (P < 0.02 for both). PS had similar cumulative shunt patency rates to those of the index shunts of Group 1, and both were greater than those of index shunts in Group 2 (P < 0.001 for both). The intervention rate (number of interventions/number of check portograms x 100) was similar for PS and the index shunts of Group 1 (38.7% and 43% respectively), but was significantly higher in the index shunts of Group 2 (85.6%; P < 0.01 for both). In Group 1 and Group 2, 144 patients (48.3%) and 21 patients (52.5%) died during follow-up after a median period of 23.4 and 8.9 months respectively.
  
  
  CONCLUSIONS
  These findings do not support the hypothesis that shunt insufficiency is related to host factors.
authors.affiliation: Department of Liver Transplantation, Hepatobiliary and Pancreatic Surgery, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia. ahsalem10@hotmail.com
authors.forename: Ahmed
authors.initials: A
authors.lastname: Helmy
authors.forename: Doris N
authors.initials: DN
authors.lastname: Redhead
authors.forename: Adrian J
authors.initials: AJ
authors.lastname: Stanley
authors.forename: Peter C
authors.initials: PC
authors.lastname: Hayes
mesh_terms: D000328:Adult; D000368:Aged; D001685:Biological Factors; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D017082:Portal Pressure; D019168:Portasystemic Shunt, Transjugular Intrahepatic / Q000379:methods* / Q000592:standards; D012189:Retrospective Studies; D015607:Stents / Q000592:standards*; D015996:Survival Rate
chemical_list: D001685:Biological Factors