( 1 ) , the transjugular intrahepatic portosystemic stent - shunt ( tipss ) has advanced to become a standard procedure in interventional radiology . today , it represents a sophisticated alternative to open surgery or endoscopy in the management of portal hypertension or its complications . the tipss shunting methodology , a shortcut between the portal vein and a liver vein , is comparable to a surgically created shunt , with the aim to lower the pressure gradient between the portal vein ( pv ) and the inferior vena cava ( ivc ) . the major achilles heel of this method during follow - up , however , is shunt reocclusion , resulting once again in a severe and harmful increase of the portal pressure ( along with all other possible complications , such as variceal bleeding or refractory ascites ) . in the past decade , multiple studies were performed in order to optimize the procedure , as well as to identify the optimal material to be used for this type of intervention . balloon - expandable stents , self - expanding stents , and polytetrafluoroethylene ( ptfe)-covered stents have been used for tipss creation in order to reduce the reocclusion rate and to thus improve long - term patency ( 2 - 4 ) . in ptfe - covered stents , the rates of patency , either short - term or at two years after tipss placement , were described as 87% and 77% , respectively ( 5 ) . ( 6 ) compared covered stents to bare - metal stents , and reported a higher two - year rate of shunt dysfunction for bare - metal stents ( 64% ) than for covered stents ( 44% ) . nevertheless , early post - tipss complications , risk of hepatic encephalopathy , and two - year survival did not differ between the groups . ( 7 ) , who concluded that while covered stents may improve patency , they do not mitigate post - shunt hepatic dysfunction and do not improve survival . notably , the cost of ptfe - covered systems greatly exceeds the cost of bare - metal stent systems . additionally , stent grafts require larger vascular sheaths and are more rigid , which makes them difficult to place in patients with very tortuous or angled vessels . therefore , bare - metal stents must still be regarded as a valuable alternative to ptfe - covered stents . here , we describe our experience using a low - profile 6f self - expanding nitinol stent system ( sinus - superflex - visual , optimed , germany ) with respect to implantability , visibility , and primary and long - term success ( including patency rates and other parameters ) . this retrospective study was approved by our institutional review board , which waived informed consent . twenty - six patients were treated with a low - profile 6f self - expanding sinus - superflex - visual stent system ( optimed , ettlingen , germany ) . all but three patients ( who were intubated and considered to be high - priority emergency cases at the time of intervention ) were informed about the procedure prior to the intervention , and gave written consent . five of the 26 patients were female ( 19% ) and 21 were male ( 81% ) . the mean age of the patients was 54.6 years , with a range of 30 - 70 years . in nine of the 26 patients , the indication for tipss creation was refractory bleeding from esophageal or gastric varices that could not be controlled endoscopically . in 18 patients , the indication for tipss creation was intractable ascites , and one patient had acute thrombosis of the confluence of the superior mesenteric and splenic veins due to necrotizing pancreatitis ( with multiple possible causes ) . the majority of our patients ( 18 out of 26 ) suffered from liver cirrhosis due to excessive alcohol consumption , and five were afflicted with active viral hepatitis . two patients had subacute budd chiari syndrome ( one without any other risk factors and the other in combination with chronic hepatitis c ) . in three patients , after ultrasound - guided puncture of the right internal jugular vein , a 0.035  glidewire ( terumo , eschborn , germany ) was positioned in the ivc . then , after dilating the subcutaneous tissue with 5f and 7f dilators , a 45-cm - long 9f sheath ( cordis endovascular , langenfeld , germany ) was inserted . with the help of a 7f multi - purpose catheter or a 5f c2 cobra catheter ( cordis endovascular ) , the right hepatic vein ( n = 23 ) or the left hepatic vein ( n = 3 ) was catheterized . midazolam , meperidine ( pethidine ) , and atropine were administered via venous access to achieve conscious sedation in the 23 patients who were not under general anesthesia . the portal vein was punctured under fluoroscopic control using 30 or 60 tipss needles ( optimed ) . then , the guide wire was advanced into the portal system , and a c2 cobra catheter ( 5f if used for venous catheterization ; otherwise 4f ) was placed deep into the superior mesenteric vein . the guidewire was subsequently replaced with an amplatz superstiff wire ( boston scientific , natick , ma , usa ) . the tipss tract was pre - dilated with a 5-mm angioplasty balloon ( fox , abbott vascular , wetzlar , germany ) , and one or two sinus - superflex - visual stents ( optimed ) were implanted under fluoroscopic control . the stent was dilated with an 8 mm or larger angioplasty balloon ( fox , abbott vascular ) if the porto - venous gradient could not be reduced to < 12 mmhg . pressure gradients between the pv and the ivc were assessed before dilatation and after establishing the shunt . if the sheath could not be advanced into the portal vein , an additional safety wire was placed into the liver vein , the tip of the sheath was placed into the junction of the liver veins , and the stent was positioned directly ( figure 1 ) . after transjugular puncture of a portal vein branch , a 4f multipurpose catheter was advanced into the portal vein , and pressure was measured within the portal vein and the right atrium via the vascular sheath , using a conventional pressure transducer ( medex ) . the porto - systemic pressure gradient was calculated as portal vein pressure minus right atrial pressure . in five of the 26 patients , persistent relevant shunting despite successful tipss placement was observed , and esophageal or gastric varices were embolized during the same session . in four patients , coils ( cook medical , bloomington , in , usa ) measuring up to a diameter of 15 mm were used , and in one patient , an amplatzer plug ( aga medical , plymouth , ma , usa ) was inserted to occlude a large gastric vein . in another four patients , who presented with refractory bleeding , a reduction of the porto - venous pressure gradient to < 8 mmhg precluded relevant shunting and was sufficient to prevent re - bleeding . all patients received a control ultrasound within the first 48 hours after tipss creation in order to rule out acute shunt occlusion . over the following month , the patients underwent doppler sonography to control for tipss patency , and had physical examinations at internal medicine outpatient clinics to monitor for clinical signs of progressive liver disease . in 19 of the 26 patients , follow - up for  5 years was documented . seven of the 26 patients escaped long - term follow - up due to a change of residence or referral back to their home hospital after successful tipss placement . due to its short half - life , unfractionated heparin can be easily antagonized in cases of re - bleeding . hence , immediately after tipss placement , every patient was placed on unfractionated heparin for at least 24 hours . full heparinization was performed with heparin 25000 iu/24 hours , for an attempted partial thromboplastin time of 55 - 70 seconds . with respect to that patient , we later abandoned the application of full heparinization after tipss . this retrospective study was approved by our institutional review board , which waived informed consent . twenty - six patients were treated with a low - profile 6f self - expanding sinus - superflex - visual stent system ( optimed , ettlingen , germany ) . all but three patients ( who were intubated and considered to be high - priority emergency cases at the time of intervention ) were informed about the procedure prior to the intervention , and gave written consent . five of the 26 patients were female ( 19% ) and 21 were male ( 81% ) . the mean age of the patients was 54.6 years , with a range of 30 - 70 years . in nine of the 26 patients , the indication for tipss creation was refractory bleeding from esophageal or gastric varices that could not be controlled endoscopically . in 18 patients , the indication for tipss creation was intractable ascites , and one patient had acute thrombosis of the confluence of the superior mesenteric and splenic veins due to necrotizing pancreatitis ( with multiple possible causes ) . the majority of our patients ( 18 out of 26 ) suffered from liver cirrhosis due to excessive alcohol consumption , and five were afflicted with active viral hepatitis . two patients had subacute budd chiari syndrome ( one without any other risk factors and the other in combination with chronic hepatitis c ) . in three patients , after ultrasound - guided puncture of the right internal jugular vein , a 0.035  glidewire ( terumo , eschborn , germany ) was positioned in the ivc . then , after dilating the subcutaneous tissue with 5f and 7f dilators , a 45-cm - long 9f sheath ( cordis endovascular , langenfeld , germany ) was inserted . with the help of a 7f multi - purpose catheter or a 5f c2 cobra catheter ( cordis endovascular ) , the right hepatic vein ( n = 23 ) or the left hepatic vein ( n = 3 ) was catheterized . midazolam , meperidine ( pethidine ) , and atropine were administered via venous access to achieve conscious sedation in the 23 patients who were not under general anesthesia . the portal vein was punctured under fluoroscopic control using 30 or 60 tipss needles ( optimed ) . then , the guide wire was advanced into the portal system , and a c2 cobra catheter ( 5f if used for venous catheterization ; otherwise 4f ) was placed deep into the superior mesenteric vein . the guidewire was subsequently replaced with an amplatz superstiff wire ( boston scientific , natick , ma , usa ) . the tipss tract was pre - dilated with a 5-mm angioplasty balloon ( fox , abbott vascular , wetzlar , germany ) , and one or two sinus - superflex - visual stents ( optimed ) were implanted under fluoroscopic control . the stent was dilated with an 8 mm or larger angioplasty balloon ( fox , abbott vascular ) if the porto - venous gradient could not be reduced to < 12 mmhg . pressure gradients between the pv and the ivc were assessed before dilatation and after establishing the shunt . if the sheath could not be advanced into the portal vein , an additional safety wire was placed into the liver vein , the tip of the sheath was placed into the junction of the liver veins , and the stent was positioned directly ( figure 1 ) . after transjugular puncture of a portal vein branch , a 4f multipurpose catheter was advanced into the portal vein , and pressure was measured within the portal vein and the right atrium via the vascular sheath , using a conventional pressure transducer ( medex ) . the porto - systemic pressure gradient was calculated as portal vein pressure minus right atrial pressure . in five of the 26 patients , persistent relevant shunting despite successful tipss placement was observed , and esophageal or gastric varices were embolized during the same session . in four patients , coils ( cook medical , bloomington , in , usa ) measuring up to a diameter of 15 mm were used , and in one patient , an amplatzer plug ( aga medical , plymouth , ma , usa ) was inserted to occlude a large gastric vein . in another four patients , who presented with refractory bleeding , a reduction of the porto - venous pressure gradient to < 8 mmhg precluded relevant shunting and was sufficient to prevent re - bleeding . all patients received a control ultrasound within the first 48 hours after tipss creation in order to rule out acute shunt occlusion . over the following month , the patients underwent doppler sonography to control for tipss patency , and had physical examinations at internal medicine outpatient clinics to monitor for clinical signs of progressive liver disease . in 19 of the 26 patients , follow - up for  5 years was documented . seven of the 26 patients escaped long - term follow - up due to a change of residence or referral back to their home hospital after successful tipss placement . tipss patency is of prime importance to reduce the risk of bleeding . due to its short half - life hence , immediately after tipss placement , every patient was placed on unfractionated heparin for at least 24 hours . full heparinization was performed with heparin 25000 iu/24 hours , for an attempted partial thromboplastin time of 55 - 70 seconds . however , one patient developed a large capsular liver hematoma . with respect to that patient , we later abandoned the application of full heparinization after tipss . tipss creation with a sinus - superflex - visual self - expandable stent was successful in all patients . in 10 patients , a single stent with a nominal diameter of 12 mm and a length of 60 mm was used ; in 13 patients , the stent length was 80 mm ; and in three patients , two stents had to be implanted ( two with 12/60 mm plus 12/80 mm sinus stents , and the other with a 12/80 mm sinus stent plus a balloon - expandable stent ) . in 24 of the 26 patients , stents were deployed exactly at the pre - planned site ( 92% ) , while in the remaining two patients , the stent was placed too deeply into the portal vein , so that an additional sinus stent ( 12/80 mm plus 12/60 mm ) had to be placed . in one patient , even though the stent length was sufficient , an additional balloon - expandable stent ( palmaz genesis , cordis endovascular , langenfeld , germany ) had to be inserted in order to achieve tract - straightening . no problems occurred with the pull - back deployment mechanisms . the mean pressure gradient prior to the intervention was 20.9  6.3 mmhg ( range : 12 - 32 mmhg ) . directly after the intervention , the pressure gradient dropped significantly to a mean of 8.2  2.3 mmhg ( range : 3 - 13 ) ( p < 0.001 ) . in 19 of 26 patients , dilating the stent with an 8-mm balloon was sufficient to lower the pressure gradient to  12 mmhg ( figure 2a and b ) . in five patients , the stent was dilated to 10 mm , and in one patient , the stent had to be dilated to 12 mm to sufficiently lower the pressure gradient . in one other patient , the stent was dilated to only 5 mm , as the indication for the procedure was to coil existing varices rather than to create a relevant shunt , due to preexisting hepatic encephalopathy . in this patient , the portosystemic pressure gradient was left at 13 mmhg . in four of the 26 patients , additional coil embolization of esophageal and/or gastric varices was performed , and in one patient , an amplatzer plug was used to occlude a large variceal vein ( figure 3a - c ) . one patient presented with acute thrombosis of the confluence of the superior mesenteric and splenic veins due to necrotizing pancreatitis . tipss insertion was successful , and the thrombotic material in the superior mesenteric and splenic veins was defragmented , leading to improved mesenteric venous flow . we observed procedure - related complications in five patients , including acute tract occlusion in two patients , liver hematoma in one , hepatic encephalopathy in one , and cardiac failure in another . one patient , who received a 12/80 mm stent for the treatment of subacute budd - chiari syndrome , suffered from an acute stent occlusion within the first 24 hours post - intervention . the tract had to be recanalized , and two additional stents ( palmaz genesis 9/59 and smart 12/80 , cordis endovascular , langenfeld , germany ) were implanted . a second patient , who was treated for refractory ascites , suffered from an acute tipss occlusion one day after tipss creation . in this patient , a viatorr stent graft ( w.l . gore , flagstaff , az , usa ) was implanted , and no occlusion subsequently occurred . a third patient , who was being treated for refractory ascites and was suffering from cirrhosis of his already - transplanted liver , developed a large liver hematoma due to excessive post - interventional anticoagulation with heparin ( ptt > 160 ) . in the course of this intrahepatic bleeding , the patient developed transient renal insufficiency . over the following six months , renal function recovered and the ascites was effectively controlled . this patient later underwent olt . a fourth patient , suffering from cirrhosis due to chronic hepatitis c , drug abuse , and excessive alcohol consumption , presented with a pre - interventional pressure gradient of 30 mmhg . post - intervention , the pressure gradient was found to be lowered to 7 mmhg . this patient subsequently developed severe hepatic encephalopathy , which was successfully controlled with conservative treatment . a fifth patient developed cardiac insufficiency six months after tipss creation . three of the 26 treated patients ( 11.5% ) died within one week after the procedure . one was due to multiorgan failure , the second was due to acute respiratory distress syndrome that complicated preexisting necrotizing pancreatitis , and the third patient died due to pulmonary exhaustion resulting from pneumonia caused by aspiration . another four of the 26 patients ( 15.4% ) died within one year after tipss creation . in one case , ascites production was found to be significantly reduced after tipss insertion ; however , this patient developed a continuously aggravating wasting syndrome and died nine months later . another patient s status progressively deteriorated due to persistent alcohol abuse and refractory ascites . in the end , he denied medical support and succumbed to his progressive liver failure at six months . another patient died with worsening ascites and hepatic encephalopathy at five months post - intervention . one patient , who received tipss because of uncontrollable bleeding from gastric varices , succumbed to re - bleeding . seven of the 26 patients underwent olt at a mean time of 9.4 months ( range : two days to 16 months ) post - intervention . one of these patients had late - onset tipss occlusion at 12 months after the tipss creation , which became symptomatic with re - bleeding of gastric varices . the tipss was recanalized and the patient received olt one month later . in the remainder of these cases , the tipss tracts were consistently patent until the moment of olt ( figure 4 ) . one became symptomatic 12 months after tipss placement , with re - bleeding from gastric varices . the other remained in good general condition , without varicose bleeding or refractory ascites , and the tipss occlusion was noticed incidentally during a routine duplex - ultrasound undertaken 39 months after tipss creation . as this patient was completely asymptomatic , tipss creation with a sinus - superflex - visual self - expandable stent was successful in all patients . in 10 patients , a single stent with a nominal diameter of 12 mm and a length of 60 mm was used ; in 13 patients , the stent length was 80 mm ; and in three patients , two stents had to be implanted ( two with 12/60 mm plus 12/80 mm sinus stents , and the other with a 12/80 mm sinus stent plus a balloon - expandable stent ) . in 24 of the 26 patients , stents were deployed exactly at the pre - planned site ( 92% ) , while in the remaining two patients , the stent was placed too deeply into the portal vein , so that an additional sinus stent ( 12/80 mm plus 12/60 mm ) had to be placed . in one patient , even though the stent length was sufficient , an additional balloon - expandable stent ( palmaz genesis , cordis endovascular , langenfeld , germany ) had to be inserted in order to achieve tract - straightening . no problems occurred with the pull - back deployment mechanisms . the mean pressure gradient prior to the intervention was 20.9  6.3 mmhg ( range : 12 - 32 mmhg ) . directly after the intervention , the pressure gradient dropped significantly to a mean of 8.2  2.3 mmhg ( range : 3 - 13 ) ( p < 0.001 ) . in 19 of 26 patients , dilating the stent with an 8-mm balloon was sufficient to lower the pressure gradient to  12 mmhg ( figure 2a and b ) . in five patients , the stent was dilated to 10 mm , and in one patient , the stent had to be dilated to 12 mm to sufficiently lower the pressure gradient . in one other patient , the stent was dilated to only 5 mm , as the indication for the procedure was to coil existing varices rather than to create a relevant shunt , due to preexisting hepatic encephalopathy . in this patient , the portosystemic pressure gradient was left at 13 mmhg . in four of the 26 patients , additional coil embolization of esophageal and/or gastric varices was performed , and in one patient , an amplatzer plug was used to occlude a large variceal vein ( figure 3a - c ) . one patient presented with acute thrombosis of the confluence of the superior mesenteric and splenic veins due to necrotizing pancreatitis . tipss insertion was successful , and the thrombotic material in the superior mesenteric and splenic veins was defragmented , leading to improved mesenteric venous flow . we observed procedure - related complications in five patients , including acute tract occlusion in two patients , liver hematoma in one , hepatic encephalopathy in one , and cardiac failure in another . one patient , who received a 12/80 mm stent for the treatment of subacute budd - chiari syndrome , suffered from an acute stent occlusion within the first 24 hours post - intervention . the tract had to be recanalized , and two additional stents ( palmaz genesis 9/59 and smart 12/80 , cordis endovascular , langenfeld , germany ) were implanted . no occlusions were subsequently observed . a second patient , who was treated for refractory ascites , suffered from an acute tipss occlusion one day after tipss creation . gore , flagstaff , az , usa ) was implanted , and no occlusion subsequently occurred . a third patient , who was being treated for refractory ascites and was suffering from cirrhosis of his already - transplanted liver , developed a large liver hematoma due to excessive post - interventional anticoagulation with heparin ( ptt > 160 ) . in the course of this intrahepatic bleeding , the patient developed transient renal insufficiency . over the following six months , renal function recovered and the ascites was effectively controlled . this patient later underwent olt . a fourth patient , suffering from cirrhosis due to chronic hepatitis c , drug abuse , and excessive alcohol consumption , presented with a pre - interventional pressure gradient of 30 mmhg . post - intervention , the pressure gradient was found to be lowered to 7 mmhg . this patient subsequently developed severe hepatic encephalopathy , which was successfully controlled with conservative treatment . a fifth patient developed cardiac insufficiency six months after tipss creation . three of the 26 treated patients ( 11.5% ) died within one week after the procedure . one was due to multiorgan failure , the second was due to acute respiratory distress syndrome that complicated preexisting necrotizing pancreatitis , and the third patient died due to pulmonary exhaustion resulting from pneumonia caused by aspiration . another four of the 26 patients ( 15.4% ) died within one year after tipss creation . in one case , ascites production was found to be significantly reduced after tipss insertion ; however , this patient developed a continuously aggravating wasting syndrome and died nine months later . another patient s status progressively deteriorated due to persistent alcohol abuse and refractory ascites . in the end , he denied medical support and succumbed to his progressive liver failure at six months . another patient died with worsening ascites and hepatic encephalopathy at five months post - intervention . one patient , who received tipss because of uncontrollable bleeding from gastric varices , succumbed to re - bleeding . seven of the 26 patients underwent olt at a mean time of 9.4 months ( range : two days to 16 months ) post - intervention . one of these patients had late - onset tipss occlusion at 12 months after the tipss creation , which became symptomatic with re - bleeding of gastric varices . the tipss was recanalized and the patient received olt one month later . in the remainder of these cases , the tipss tracts were consistently patent until the moment of olt ( figure 4 ) . one became symptomatic 12 months after tipss placement , with re - bleeding from gastric varices . the other remained in good general condition , without varicose bleeding or refractory ascites , and the tipss occlusion was noticed incidentally during a routine duplex - ultrasound undertaken 39 months after tipss creation . as this patient was completely asymptomatic , tipss is the treatment of choice to manage the complications of portal hypertension , such as variceal hemorrhage or refractory ascites , when conservative or endoscopic procedures have failed . tipss creation significantly reduces the risk of bleeding from esophageal or gastric varices ( 8 , 9 ) , and is superior to conservative therapy in treating refractory ascites ( 10 ) . however , establishing a tipss is associated with a significantly higher risk of hepatic encephalopathy ( 8 , 10 , 11 ) , as blood from the gi tract bypasses the liver and detoxification is significantly reduced . nevertheless , hepatic encephalopathy following tipss creation can be managed conservatively in the majority of cases . the technical success rate of establishing a proper shunt between the pv and the ivc has risen to approximately 95% over the years , due to the development of sophisticated tools , including low - profile balloons and stents ( 12 , 13 ) . meanwhile , several stents or stent grafts have been evaluated for tipss creation . in the early days , stents such as balloon - expandable palmaz stents were used with technical success rates ranging between 75% and 95% ( 14 - 16 ) . subsequently , self - expanding stents such as the wallstent have been evaluated ( 16 , 17 ) , and more recently , stent grafts such as the viatorr have been used ( 18 , 19 ) . compared to bare - metal stents , the long - term patency rates of stent grafts are higher , as no pseudointimal hyperplasia occludes the tract lumen . however , those grafts require larger vascular sheaths and , due to their rigidity , they can be difficult to place in patients with very tortuous or angled vessels . in this paper , we describe our experience with a 6f self - expanding nitinol stent system . in order to enhance its visibility , radiopaque tantalum markers are fixed to the stent at both ends , which can be helpful during abdominal interventions , especially in obese patients or when using a flat - panel ( digital ) angiography unit ( 20 ) . due to its low profile and flexibility , this stent system can be introduced even if the transhepatic tract is very sloped . furthermore , this system can be advanced through the pre - dilated liver parenchyma without the sheath having to be placed within the portal vein , making tipss establishment much easier , at least in some cases . when using , for example , a 9f vascular sheath , a second wire can be placed through the sheath for anchoring and stabilizing the vascular sheath in the liver vein ( figure 1 ) . this is advantageous when the angle between the liver veins and the ivc is close to 90 , or when the ivc is found to be dilated . we exclusively chose stents with a diameter of 12 mm , to have the option of creating single shunts with a large diameter in order to avoid the implantation of a second , parallel shunt ( 21 ) . in one patient , it was necessary to dilate the stent with a 12 mm balloon in order to sufficiently lower the pressure gradient . in 25 of 26 patients , we were able to reduce the portosystemic pressure gradient to  12 mmhg , which is considered the therapeutic goal , at the time of tipss creation ( 22 , 23 ) . thus , the low - profile sinus - superflex - visual stent was demonstrated to be powerful enough to achieve the therapeutically required pressure reduction . in one patient , we did not dilate the tract after stent placement , as our specific goal in this case was merely to embolize the variceal veins , which were the source of repetitive bleeding . we did not dilate the tract , due to preexisting hepatic encephalopathy , and we did not choose an abdominal percutaneous approach for coil embolization , due to ascites . additional embolization of variceal ( esophageal and/or gastric ) veins was performed in five of our 26 patients . in those five patients , the variceal veins still presented with the relevant shunting , although a tipss was created successfully and the portosystemic pressure had been lowered significantly , to below the threshold of 12 mmhg . as the indication for tipss creation in these patients was recurrent bleeding , we intended to lower the risk of re - bleeding by performing this additional procedure ( 24 ) . in four of these five patients , coil embolization was performed , and in one patient , an amplatzer plug was inserted ( figure 3a - c ) . in all patients , the varices no longer opacified after the intervention . we observed relevant periprocedural complications in five of our 26 patients that were procedure - related rather than stent - related . one liver hematoma was caused in the course of the multiple punctures required to establish portal venous access , and by a prolonged ptt of > 160 seconds due to unintentional excessive administration of heparin . in another patient , this early stent occlusion was likely due to the stent length chosen for the procedure ; the stent did not completely cover the liver vein , which has been described as a reason for tipss failure by other groups ( 4 , 16 ) . a re - intervention with the implantation of two additional stents was necessary , and no further adverse events were noted thereafter in this patient . another patient with acute tract occlusion was treated with the additional implantation of a viatorr stent . a patient with hepatic encephalopathy one patient with cardiac decompensation six months after tipss creation was treated using a tipss reduction stent system . overall , three patients died within one week after tipss creation , attributable to their limited general conditions ( multiorgan failure , ards , pneumonia ) rather than to the tipss creation . by and large , the rate of adverse effects was concordant with the rate of tipss - related complications already published in the literature ( 25 , 26 ) . apparently , those side effects were procedure - related rather than graft - related . with regard to long - term follow - up , four of the 26 patients in this study succumbed to their underlying advanced liver disease within one year after tipss insertion . in addition , three patients exhibited late - onset tipss occlusions ( at 12 , 12 , and 39 months after tipss creation ) . overall , the long - term disease courses and late complications were found to be comparable to those reported by other groups ( 6 , 7 ) . therefore , the tipss procedure is regarded as a highly effective bridge to liver transplantation , especially in patients with complications resulting from severe portal hypertension , and who are candidates for olt . indeed , seven of the 26 patients in this study underwent olt at a mean time of 9.4 months after tipss creation . the shunt did not impair liver transplantation in any of these patients , which is in line with the results obtained in other studies ( 27 , 28 ) . initially , our intention was to  only  treat the patients , not to evaluate or compare the function of different stent devices . prospective , randomized trials focusing on patient survival are needed in order to compare the sinus - superflex - visual stent to other stent systems , and to avoid bias due to incomplete follow - up and retrospective analysis . second , seven of the 26 patients escaped long - term follow - up due to a change of residence or referral back to their home hospital after successful tipss placement . third , although the majority of our tipss patients most likely resembled each other with respect to their underlying conditions ( i.e. alcoholism , viral hepatitis , cryptogenic cirrhosis , etc . ) , we can not rule out that the stent system described in our analysis might be less beneficial in special subgroups of patients . in conclusion , the sinus - superflex - visual stent system was found to be easily deployed even in the presence of disadvantageous vascular anatomy . the achieved rate of pressure gradient reduction ( from a mean of 20.9 mmhg to a mean of 8.2 mmhg ) was clinically sufficient to treat symptoms resulting from portal hypertension , and the rate of adverse effects was found to be similar to that of previously published data .
backgroundthe transjugular intrahepatic portosystemic stent - shunt ( tipss ) builds a shortcut between the portal vein and a liver vein , and represents a sophisticated alternative to open surgery in the management of portal hypertension or its complications.objectivesto describe clinical experiences with a low - profile nitinol stent system in tipss creation , and to assess primary and long - term success.patients and methodstwenty - six patients ( 5 females , 21 males ; mean age 54.6 years ) were treated using a low - profile 6f self - expanding sinus - superflex - visual stent system . 
 the indication for tipss creation was refractory bleeding in 9 of the 26 patients , refractory ascites in 18 patients , and acute thrombosis of the portal vein confluence in one patient . 
 portosystemic pressure gradients before and after tipss , periprocedural and long - term complications , and the time to orthotopic liver transplantation ( olt ) or death were recorded.resultsthe portosystemic pressure gradient was significantly reduced , from 20.9  6.3 mmhg before to 8.2  2.3 mmhg after tipss creation ( p < 0.001 ) . 
 procedure - related complications included acute tract occlusion ( n = 2 ) , liver hematoma ( n = 1 ) , hepatic encephalopathy ( n = 1 ) , and cardiac failure ( n = 1 ) . 
 three of the 26 patients had late - onset tipss occlusion ( at 12 , 12 , and 39 months after tipss creation ) . 
 three patients died within one week after the procedure due to their poor general condition ( multiorgan failure , acute respiratory distress syndrome , necrotizing pancreatitis , and aspiration pneumonia ) . 
 another four patients succumbed to their underlying advanced liver disease within one year after tipss insertion . 
 seven patients underwent olt at a mean time of 9.4 months after tipss creation.conclusionthe sinus - superflex - visual stent system can be safely deployed as a tipss device . 
 the pressure gradient reduction was clinically sufficient to treat the patients symptoms , and periprocedural complications were due to the tipss procedure per se rather than to the particular stent system employed in this study .