title: Is sonographic surveillance of polytetrafluoroethylene-covered transjugular intrahepatic portosystemic shunts (TIPS) necessary? A single centre experience comparing both types of stents.
abstract: OBJECTIVE
  To investigate whether sonographic (US) surveillance of polytetrafluoroethylene covered transjugular intrahepatic portosystemic shunts (TIPS) is necessary.
  
  
  METHODS
  We identified 128 patients who underwent TIPS for complications of portal hypertension between January 2001 and December 2005 at a large tertiary centre. Procedural data were retrospectively analysed. US surveillance of the TIPS was performed at baseline with scheduled follow-up or whenever shunt dysfunction was suspected. Clinical and radiology reports were compared to assess US surveillance of the TIPS.
  
  
  RESULTS
  Four hundred and twenty-six US studies were performed, with a median of three per patient (range 1-5). The median follow-up period was 378 days (range 1-1749 days). Twenty-three patients (18%) had baseline US studies performed only whereas 105 (82%) also had follow-up studies. Forty-one (32%) of 128 patients [32 (78%) Wallstent, nine (22%) Viatorr] had Doppler ultrasound abnormalities noted. Venography was performed in all 41 patients. Abnormal venography and elevated hepatic venous pressure gradient (HVPG) was seen in 34 (82.9%) of the 41 patients [29 (85.3%) Wallstent, five (14.7%) Viatorr]. Among the 34 patients, 17 (50%) [13 (76.5%) Wallstent, four (23.5%) Viatorr] had venographic abnormalities noted at the hepatic venous end accompanied by increased HVPG. All four of the Viatorr patients had minor narrowing at the hepatic venous end and HVPG measurements that ranged 3-4 mm Hg above 12 mm Hg.
  
  
  CONCLUSIONS
  Considering the improved patency of covered stents in TIPS, US surveillance may be superfluous after the baseline study.
authors.affiliation: Department of Medicine, Division of Gastroenterology, Section of Hepatobiliary Disease, University of Florida, Gainesville, FL 32610, USA.
authors.forename: J-J
authors.initials: JJ
authors.lastname: Pan
authors.forename: C
authors.initials: C
authors.lastname: Chen
authors.forename: B
authors.initials: B
authors.lastname: Geller
authors.forename: R
authors.initials: R
authors.lastname: Firpi
authors.forename: V I
authors.initials: VI
authors.lastname: Machicao
authors.forename: J G
authors.initials: JG
authors.lastname: Caridi
authors.forename: D R
authors.initials: DR
authors.lastname: Nelson
authors.forename: G
authors.initials: G
authors.lastname: Morelli
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D020099:Coated Materials, Biocompatible; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006975:Hypertension, Portal / Q000601:surgery*; D008134:Long-Term Care / Q000379:methods; D008297:Male; D008875:Middle Aged; D011138:Polytetrafluoroethylene; D019168:Portasystemic Shunt, Transjugular Intrahepatic / Q000295:instrumentation* / Q000379:methods; D011172:Portography; D011182:Postoperative Care / Q000379:methods; D011475:Prosthesis Failure; D012189:Retrospective Studies; D015607:Stents; D018608:Ultrasonography, Doppler; D019564:Unnecessary Procedures; D014654:Vascular Patency
chemical_list: D020099:Coated Materials, Biocompatible; D011138:Polytetrafluoroethylene