title: Retrospective comparison of the patency of Wallstents and Palmaz long-medium stents used for TIPS. Transjugular intrahepatic portosystemic shunts.
abstract: OBJECTIVE
  To compare patency rates of transjugular intrahepatic portosystemic shunts (TIPS) after placement of long-medium Palmaz stents or Wallstents.
  
  
  METHODS
  We performed a retrospective review of TIPS performed at our institution between December 1997 and December 1998. During this time period we placed long-medium Palmaz stents for TIPS procedures in 17 patients and Wallstents in 20 patients as the initial stent. Patency was determined on follow-up by ultrasound, angiography, or pathologic examination in the event of transplant.
  
  
  RESULTS
  Primary patency in the Palmaz stent group was 70.6% (12/17 patients) (follow-up 1-399 days, mean 127 days). Both primary assisted and secondary patency in the Palmaz group was 100% (17/17 patients) (follow up 1-399 days, mean 154 days). Primary patency in the Wallstent group was 50% (10/20 patients) (follow up 1-370 days, mean 65 days). Primary assisted patency in the Wallstent group was 80% (16/20 patients) (follow up 1-601 days, mean 141 days). Secondary patency in the Wallstent group was 100% (20/20 patients) (follow up 2-601 days, mean 142 days). Kaplan-Meier analysis of the two groups of patients yielded a primary patency of 266 days (standard error 45 days) for TIPS with the Palmaz stent and 139 days (standard error 45 days) for the Wallstent (p =.04). The 3, 6, and 12-month primary patency rates were .84, .63, and .42 respectively for the Palmaz stents and .36, .36, and .18 respectively for the Wallstent. There was no significant difference in primary assisted or secondary patency between the two stent groups. The mean tract curvature in the patients with Palmaz stents was 23.5 degrees (SD 18.2 degrees, range 0-69.0 degrees ) compared with 57 degrees (SD 34.5 degrees, range 7.0-144.0 degrees ) in patients with Wallstents (p =.01).
  
  
  CONCLUSIONS
  Our nonprospective, nonrandomized study suggests that TIPS created with the long-medium Palmaz stent have a higher primary patency than those created with the Wallstent in tracts that are relatively straight.
authors.affiliation: Department of Radiology, University of Washington Medical Center, Box 357115, 1959 NE Pacific Street, Seattle, WA 98195, USA. jjborsa@u.washington.edu
authors.forename: J J
authors.initials: JJ
authors.lastname: Borsa
authors.forename: A B
authors.initials: AB
authors.lastname: Fontaine
authors.forename: E K
authors.initials: EK
authors.lastname: Hoffer
authors.forename: R D
authors.initials: RD
authors.lastname: Bloch
authors.forename: E
authors.initials: E
authors.lastname: Tong
authors.forename: C S
authors.initials: CS
authors.lastname: Kuhr
authors.forename: K V
authors.initials: KV
authors.lastname: Kowdley
authors.forename: U P
authors.initials: UP
authors.lastname: Schmiedl
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography; D001201:Ascites / Q000601:surgery; D004932:Esophageal and Gastric Varices / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006471:Gastrointestinal Hemorrhage / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D019168:Portasystemic Shunt, Transjugular Intrahepatic / Q000295:instrumentation*; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D015607:Stents; D016019:Survival Analysis; D018084:Ultrasonography, Interventional; D014654:Vascular Patency