title: Portosystemic pressure gradient during transjugular intrahepatic portosystemic shunt with Viatorr stent graft: what is the critical low threshold to avoid medically uncontrolled low pressure gradient related complications?
abstract: BACKGROUND
  Inappropriately decreased portosystemic pressure gradient (PSG) during transjugular intrahepatic portosystemic shunt (TIPS) can cause fatal complications but the critical low threshold of PSG is still not clear. The aim of the present study was to evaluate the critical low threshold of PSG during TIPS.
  
  
  METHODS
  Sixty-six patients with cirrhosis who successfully underwent de novo TIPS with Viatorr stent grafts were studied. Medically uncontrolled low pressure gradient (LPR) complication was defined as when a patient died, or when acute transplantation or a TIPS reduction procedure was performed due to refractory encephalopathy or the deterioration of hepatic function within 3 months after the procedure. For the determination of the risk group for medically uncontrolled LPR complications, the Child-Pugh score and the model of end-stage liver disease (MELD) score showing a 100% negative predictive value was decided on as a threshold for each score. The risk group was defined when either of both scores was higher than its threshold. For the determination of a critical low post-TIPS PSG, a value of post-TIPS PSG showing the highest discrimination power on the receiver operating characteristic (ROC) curve in the risk group was decided on as a critical low threshold of PSG. The medically uncontrolled LPR complication rates of the patients with the determined threshold or lower were evaluated for the risk group.
  
  
  RESULTS
  Medically uncontrolled LPR complications developed in nine patients (13.6%). Five patients died and four patients had TIPS reduction procedures. Patients with more than 10 on the Child-Pugh score or more than 14 on the MELD score were determined to be the risk group and 34 patients were included. The critical lower threshold of the post-TIPS PSG showing the highest discrimination power on the ROC curve was 5 mmHg (sensitivity 100%, specificity 72%), and the medically uncontrolled LPR complication rates of the patients with 5 mmHg or lower on the post-TIPS PSG were 56.3% (9/16) in the risk group.
  
  
  CONCLUSIONS
  The critical threshold of the post-TIPS PSG to avoid the medically uncontrolled LPR complications of TIPS was >5 mmHg. The PSG should not be reduced below this level in the risk group.
authors.affiliation: Department of Diagnostic Radiology, Ansan Hospital, Korea University College of Medicine, Ansan City, Kyonggido, South Korea. chungmic@korea.ac.kr
authors.forename: Hwan-Hoon
authors.initials: HH
authors.lastname: Chung
authors.forename: Mahmood K
authors.initials: MK
authors.lastname: Razavi
authors.forename: Daniel Y
authors.initials: DY
authors.lastname: Sze
authors.forename: Joan K
authors.initials: JK
authors.lastname: Frisoli
authors.forename: Stephen T
authors.initials: ST
authors.lastname: Kee
authors.forename: Michael D
authors.initials: MD
authors.lastname: Dake
authors.forename: Jeffrey C
authors.initials: JC
authors.lastname: Hellinger
authors.forename: Byung-Chul
authors.initials: BC
authors.lastname: Kang
mesh_terms: D001794:Blood Pressure / Q000502:physiology; D005260:Female; D006501:Hepatic Encephalopathy / Q000209:etiology / Q000401:mortality; D006801:Humans; D006975:Hypertension, Portal / Q000601:surgery*; D007022:Hypotension / Q000209:etiology / Q000401:mortality*; D008102:Liver Circulation / Q000502:physiology; D017093:Liver Failure / Q000209:etiology / Q000401:mortality; D008297:Male; D008875:Middle Aged; D011168:Portal System / Q000503:physiopathology*; D019168:Portasystemic Shunt, Transjugular Intrahepatic / Q000009:adverse effects* / Q000401:mortality; D015607:Stents / Q000009:adverse effects