Transjugular Intrahepatic Portosystemic Shunt With Covered Stent:Technical Aspects And Clinical Applications

BackgroundTransjugular intrahepatic portosystemic shunts (TIPS) have been increasingly used for the treatment of complications of portal hypertension in patients with cirrhosis. However, one of the main drawbacks is the high rate of shunt dysfunction, reported in30-70%within the first year. Recently, the use of a new generation of polytetrafluoroethyoethylene covered stent stent (Viatorr stent, GORE, Flagstaff, AZ, USA) overcame the problem of shunt dysfunction with significant improvement in TIPS patency and clinical efficacy. In the2009practice guidelines about TIPS by the American Association for the Study of Liver Diseases (AASLD), use of expanded PTFE-covered stents is now preferred.Unfortunately, the most common used Viatorr stent is not commercially available in our country. So we choose Fluency stent (Bard Inc, Germany) istead of Viatorr stent to complete TIPS. Fluency stent is all covered (except2mm bare segment) and the cover material is the same as Viatorr stent-graft with PTFE, in addition to this, the carbon impregnation technology applied in inner surface of Fluency stent can decrease platelet accumulation, which can also reduce the incidence of restenosis. Reunderstanding th safety and feasibility of Fluency stent should be of value to promote the development of TIPS.PurposeThe purpose of this study are to desceribe the results of a prospective trial on the technical improvement of transjugular intrahepatic portosystemic shunts (TIPS) using polytetrafluoroethyoethylene covered stent (Fluency covered stent. Bard Corp), and to evaluate the clinical application of covered stent TIPS for the treatment of portal hypertention.Materials and Methods1. To evaluate the clinical effect of TIPS with covered stent and analyze the affected factorsFrom Oct,2005to Jul,2011,102patients (82men and20women; mean age:52.6) with portal hypertension according to liver cirrhosis underwent TIPS with covered-stent. The causes of liver cirrhosis were hepatitis B (n=82), alcohol abuse (n=8), Budd-Chiari syndrome (n=5), hepatitis C (n=4) and cryptogenic cause (n=3). Indications for treatment were variceal bleeding (n=83), refractory ascites (n=19). Fifty-five patients had Child-Pugh class A cirrhosis;41had Child-Pugh Class B; and9, Child-Pugh class C. All patients underwent clinical follow-up at3,6,12,24,36,48months after TIPS and the end-point was Jan,2011. Cumulative patency of shunt with covered stent, hepatic encephalopathy (HE) and survial rates were calculated with the life-talble method, Stepwise multiple Cox regression analyses wre performed to assess factors influencing shunt malfunction and HE rate and mortality.2. To discuss the clinical application of TIPS with covered stent in the treatment of portal hypertension accompanying main portal vein tumor thrombus (MPVTT).A cohort of5patients with portal hypertension due to primary liver cancer complicated by portal vein thrombosis were selected,3having clinical manifestations of esophagogastric varicosis and acute massive upper gastrointestinal bleeding, the other2having refractory ascites. All the patients received TIPS with Fluency covered stent. Portal pressures before and after the stent implantation were measured. All the patients were followed up2to12months to analyze their therapeutic outcomes.Results1. To evaluate the clinical effect of TIPS with covered stent and analyze the affected factorsThe procedure was successful in all102patietns. The mean portosystemic pressure of portal vein decreased from38.1cmH20to23.7cmH20(paired t, p<0.01). Three TIPS-related complications occurred (two cases of serious hemopertoneum and one infection arround covered-stent). Forty-two patients reached the end-point before Jan,2012, including shunt restenosis (n=10,9.8%), death according to different causes (n=16,15.7%), orthotopic liver transplantation (n=3,2.9%), primary hepatocellular carcinoma (n=7,6.9%) and lost, six (5.9%). During the follow-up, shunt restenosis occurred in10patients (9.8%), Cumulative primary patency rates were96%,91%,82%,82%and82%at6,12,24,36and48months, respectively. The hepatic vein location of stent was independent affect fator of shunt restenosis (P=0.000). postprocedural HE occurred in27patients (26.5%), Cumulative HE rates were7%,21%,34%,46%and66%at6,12,24,36and48months, respectively. The affect fator of HE rates included Child-pugh class before TIPS and potal vein post cover-stent implanted(p=0.000,0.007, respectively). The overall mortality rare was15.7%(n=16), Cumulative survial rates were95%,83%,76%,76%and76%at6,12,24,36and48months, respectively. The affect factors of survial rates included Child-pugh class and pressure of potal vein before TIPS (P=0.001,0.011, respectively).2. To discuss the clinical application of TIPS with covered stent in the treatment of portal hypertension accompanying main portal vein tumor thrombus (MPVTT).TIPS was successfully performed in all the5patients, with9covered stents implanted including8with a diameter of8mm and1with a diameter of7mm. The length of implanted stents ranged from6to8cm. The preoperative mean pressure difference between portal vein and right atrium (PSG),37.8mmHg (33-45mmHg), decreased to12.0mmHg (7-20mmHg) after the procedure. Two cases had a transient memory loss at1week after the surgery that was cured by giving oral lactulose as well as other medications. All the3cases with acute massive upper gastrointestinal bleeding were cured with hemostasis after the surgery, and refractory ascites of the other2patients was obviously alleviated. During the follow-up, ultrasound indicated smooth blood flow through the stent and there was no recurrence of symptoms. Death occurred2months after the procedure in2cases and4months after the procedure in another2cases, with all due to multiple organs failure, and the other1patient survived the12months follow-up.ConclusionsThe Fluency covered stent is safe and effective in TIPS, with clear improvement of shunt patency, without increasing the risk of hepatic encephalopathy and with a trend towards better survival.TIPS with Fluency covered stent is feasible for patients with portal hypertension accompanying main portal vein tumor thrombus. The procedure can effectively control the short-term symptoms related to portal hypertension.