Transjugular Intrahepatic Portosystemic Shunt Flow Reduction with Adjustable Polytetrafluoroethylene-covered Balloon-expandable Stents

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1 Transjugular Intrahepatic Portosystemic Shunt Flow Reduction with Adjustable Polytetrafluoroethylene-covered Balloon-expandable Stents Ghazwan Kroma, MD, Jorge Lopera, MD, PhD, Marco Cura, MD, Rajeev Suri, MD, Fadi El-Merhi, MD, and Jerad Reading, MD Creation of a transjugular intrahepatic portosystemic shunt (TIPS) can effectively treat complications of portal hypertension, but excessive shunting can cause life-threatening hepatic encephalopathy and hepatic insufficiency. The present report describes a novel technique that allows for controlled and adjustable flow reduction through the TIPS via partial closure of the shunt with a balloon-mounted covered stent. The method results in clinical improvement of hepatic encephalopathy and hepatic insufficiency and immediate increase in the portosystemic pressure gradient. However, among the four patients described herein, survival beyond 1 year was seen in only one, who underwent liver transplantation after TIPS reduction. J Vasc Interv Radiol 2009; 20: Abbreviations: PET polyethylene terephthalate, PTFE polytetrafluoroethylene, TIPS transjugular intrahepatic portosystemic shunt From the Department of Interventional Radiology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, Mail Stop 7800, San Antonio, TX Received June 3, 2008; final revision received March 16, 2009; accepted March 24, Address correspondence to G.K.; kroma@uthscsa.edu None of the authors have identified a conflict of interest SIR, 2009 DOI: /j.jvir TRANSJUGULAR intrahepatic portosystemic shunt (TIPS) creation has replaced the traditional approach of surgical creation of a portosystemic shunt in the treatment of portal hypertension sequelae such as variceal bleeding and refractory ascites. However, hepatic encephalopathy, hepatic insufficiency, and congestive heart failure are frequent and problematic complications of this procedure. New or worsened encephalopathy after TIPS creation has been reported to occur in 17% 46% of patients (1). The majority of these patients show a favorable response to medical management consisting of catharsis, bowel sterilization, and protein restriction; however, complications after TIPS creation remain refractory to medical management in 3% 7% of patients (1 3). Fulminant hepatic failure can occur in as many as 3% of patients after TIPS creation (1). Rates of mortality from fulminant hepatic failure after TIPS creation have been reported to be 14% 16% (1,2). In these patients, emergent transplantation or TIPS reduction are the most effective treatment options (4,5). Hepatic encephalopathy and insufficiency after TIPS creation are thought to be secondary to increased shunting of portal venous toxins to the systemic circulation and from hypoperfusion and ischemia of the hepatocytes (6,7). Methods that reduce the shunt diameter may represent treatment options when emergency transplantation is not available. A variety of TIPS reduction techniques have been described, but most are time-consuming and require earlier manipulation of the materials. Our modified technique of TIPS flow reduction involves inflating a balloonmounted covered stent that inflates at the edges first in an hourglass shape. A similar technique was described in 2001 (8), and herein we describe technical modifications we believe offer further advantages compared with the original technique. In this report, we described these modifications and the results of their application in four patients. MATERIALS AND METHODS The institutional review board at our university did not require approval for this retrospective case series. Between May 2006 and February 2008, 58 patients underwent a TIPS procedure at our institution. Three men and one woman (mean age, 55 years; age range, y) among the 58 patients needed TIPS reduction for TIPS-related complications after a lack of response to medical management. The initial indication for TIPS was refractory ascites for patients 1 and 2, variceal bleeding for patient 3, and both in patient 4. Patient 3 981

2 982 TIPS Reduction with Adjustable Covered Balloon-expandable Stent July 2009 JVIR Table 1 Clinical and Technical Data on the Patient Cohort Pt. No. Age (y)/sex Indication Before TIPS After TIPS PSG (mm Hg) Before Reduction After Reduction Stent-graft for Initial TIPS 1 47/M Refractory ascites Viatorr 10 mm (8 2) cm 2 61/M Refractory ascites Viatorr 10 mm (8 2) cm 3 55/M Variceal bleeding Viatorr 10 mm (6 2) cm 4 67/F Variceal bleeding Viatorr 10 mm and refractory (5 2) cm ascites Device Used for Reduction 38 mm 59 mm 38 mm 38 mm Shunt Reduction (%) presented to the emergency department with refractory upper gastrointestinal bleeding, lethargy, disorientation, and slurred speech (ie, grade 2 hepatic encephalopathy based on West Haven Criteria of altered mental status in hepatic encephalopathy). Two of the patients had hepatitis C and alcoholic liver disease, one had alcoholic liver disease, and one had hepatitis C liver disease. A self-expanding polytetrafluoroethylene (PTFE) covered stent (Viatorr; W.L. Gore and Associates, Flagstaff, Arizona) was placed in all four patients during the initial TIPS procedure. Complications after TIPS creation included hepatic encephalopathy in patient 4, hepatic insufficiency in patients 1 and 2, and both in patient 3. Three of the patients developed hepatic encephalopathy and/or hepatic insufficiency within 2 weeks of the TIPS procedure and the fourth patient developed hepatic encephalopathy approximately 3 months after TIPS creation. All four patients underwent TIPS flow reduction with a PTFEcovered balloon-expandable stent (icast; Atrium Medical, Hudson, New Hampshire). The mean time between the TIPS procedure and the reduction was 35 days (range, d). Table 1 lists the clinical and technical data of the four patients treated. Reduction Technique Venous access was obtained through the right internal jugular vein, and a 7-F, 25-cm sheath (Cook, Bloomington, Indiana) was advanced into the right atrium. The shunt was catheterized with a 5-F Multi-Purpose A catheter (Cook). Initial portography and pressure measurements were performed with an Omni-flush catheter (Angio- Dynamics, Queensbury, New York) positioned in the splenic vein (Fig 1a). Over a inch Amplatz wire (Cook), the OmniFlush catheter was removed and the sheath advanced into the shunt. The icast covered stent was then deployed within the Viatorr covered stent. In patients 1, 2, and 4, a mm icast covered stent was used. In patient 2, a mm icast covered stent was placed. The icast balloon-mounted covered stents were only partially inflated to ensure a narrow waist (Fig 1b). However, when we attempted to pull the deflated balloon from the partially inflated covered stent, the stent migrated slightly proximally in each of the four patients. The possible reasons for this instability are as follows: first, the deflated balloon snagged the narrow waist of the covered stent during removal of the balloon, which was managed by further dilating the covered stent; and second, there was a lack of friction between the Viatorr device and the icast covered stents, which was treated by inflating a mm angioplasty balloon (Cook) at the proximal and distal ends of the icast covered stents to ensure better sealing (Fig 1c, 1d). In one case, despite the aforementioned maneuvers, the covered stent moved slightly within the Viatorr stent as the sheath was pulled. For this case, a mm overlapping balloon-expandable uncovered stent (Lifestent; Edwards Lifesciences, Irvine, California) was deployed proximal to the icast stent to anchor it (Fig 1e). After deploying and securing the icast stent, portography and hemodynamic measurements were repeated (Fig 1f). No specific pressure gradient was used and reestablishment of minimal antegrade flow into the intrahepatic portal veins was used as the endpoint. Balloon expansion of the covered stent was performed to increase the flow through the shunt as needed. Prominent gastric varices were noted in patient 3 after TIPS reduction and were embolized with coils to prevent any future bleeding. RESULTS The TIPS reduction procedure was successfully performed in all four patients (ie, 100% technical success rate), reestablishing venographically evident minimal hepatopetal flow in intrahepatic portal veins. All icast covered stents functioned adequately and inflated in an ideal hourglass shape. All patients showed a reduction of shunt flow (mean reduction, 59.2%; range, 50% 67%) as indicated by an increase in portosystemic pressure gradients (mean increase, 8 mm Hg; range, 6 19 mm Hg). Hemodynamic outcomes associated with the procedures are summarized in Table 1. An increase of the portosystemic gradient to greater than the conventional target of 12 mm Hg was required in all patients to establish antegrade flow in the intrahepatic portal veins. No variceal hemorrhage after TIPS reduction was seen in any patient during the follow-up period; however, patient 3

3 Volume 20 Number 7 Kroma et al 983 Figure 1. TIPS flow reduction achieved with the use of a balloon-mounted covered stent. (a) Initial portogram showed no intrahepatic portal venous flow. (b) Partial deployment of the balloon-mounted covered stent insured a narrow waist of the stent (arrowhead) within the original shunt (arrows). Balloon angioplasty of the covered stent at the proximal (c) and distal (d) edges was performed for better sealing with the TIPS. (e) A balloon-expandable bare stent (arrowhead) was deployed overlapping the proximal segment of the covered stent (arrow) to anchor it. (f) Final portogram showed moderate filling of intrahepatic portal veins (arrows). underwent variceal embolization at the time of the TIPS reduction as a result of reopacification of large gastric varices. Only one patient (patient 1) showed a reaccumulation of ascites during follow-up, but no paracentesis was required. Plasma ammonia level decreased in three patients, and a measurement was not available in patient 1; however, correlation between ammonia levels and clinical state is imperfect. Total bilirubin level decreased in three patients but increased slightly in patient 2. Two patients died within 30 days of the procedure from multipleorgan failure. One patient exhibited resolved hepatic insufficiency after TIPS reduction and follow-up ultrasound imaging of the TIPS 4 months after the procedure demonstrated a patent shunt. Long-term survival is limited to only one patient who received a liver transplant within 1 week of TIPS reduction; that patient died of posttransplantation lymphoproliferative disease 18 months after transplantation. Clinical responses and final outcomes after TIPS reductions are summarized in Table 2. Mean and median overall survival time after TIPS reduction were 148 and 68 days, respectively, including the transplant recipient; and 50 and 14 days, respectively, excluding that patient.

4 984 TIPS Reduction with Adjustable Covered Balloon-expandable Stent July 2009 JVIR Table 2 Clinical Responses and Final Outcomes after TIPS Reduction Plasma Ammonia Total Bilirubin International Normalized Ratio MELD Score Hepatic Encephalopathy Stage Pt. No. Before After Before After Before After Before After Before After Clinical Outcome 1 NA NA Hepatic insufficiency resolved with recurrent ascites that improved after 2 months; not a transplantation candidate; died 4.5 mo later Hepatic insufficiency continued to deteriorate; transplantation performed within 1 week; died of PTLD 18 mo after treatment Died of hepatic insufficiency and hepatorenal syndrome 7 days after reduction Slight improvement in hepatic encephalopathy for first 3 d, then deteriorated; died of hepatic insufficiency and encephalopathy 2 weeks after Note. MELD Model for End-stage Liver Disease; NA not available; PTLD posttransplantation lymphoproliferative disease. DISCUSSION In general, TIPS reduction is reserved for patients who show the development of hepatic encephalopathy or hepatic failure after TIPS creation and in whom medical treatment has failed. The treatment of choice in such cases is immediate liver transplantation; however, a shortage in organ donation limits this option, and TIPS occlusion or reduction represents a temporary alternative therapy that can help to relieve these conditions and serve as a bridge therapy to liver transplantation. Occlusion is favored by some researchers in cases of fulminant liver failure or severe encephalopathy (4). These occlusion procedures are known to induce a rapid increase in portal venous pressure, which can cause variceal bleeding and heart failure with potentially lethal impact (9). Considering the problems associated with complete TIPS occlusion, several techniques have been described to reduce the diameter of the TIPS. Haskal et al (4) initially described the creation of a narrowing in the center of a Wallstent with a suture and subsequent deployment within the existing TIPS. This technique was thought to cause increased friction through the narrowed stent and reduced flow, resulting in clinical improvement. Another technique described by Forauer and McLean (10) used a balloon-expandable noncovered stent over a self-expanding noncovered stent. The stent was deployed, and selective balloon dilation allowed expansion of the stent distal and proximal to the narrowed waist. Constrained uncovered stents have shown positive yet unpredictable results, as the time from constrained stent placement to portosystemic pressure gradient increase is greatly varied. Attempts have been made to embolize the space between the existing TIPS and narrowed waist of the reduced stent, with embolic emulsion to reduce this time (5). The use of covered stents eliminated the time delay from stent placement to portosystemic gradient increase by preventing flow through the stent interspace and providing immediate increase in the portosystemic pressure gradient. One method described the use of a polyethylene terephthalate (PET) covered Wallgraft (Boston Scientific, Natick, Massachusetts) constrained by a central suture in six patients (11). Although an immediate portosystemic shunt gradient increase was observed in all patients, shunt occlusion occurred in two of the patients within 8 months. A study comparing PTFE-covered and PET-covered stents in a porcine model (12) demonstrated superior patency with the PTFE-covered stents. A report by Jacquier et al (13) described the coaxial deployment of a PET-covered Wallgraft into a Wallstent (Boston Scientific) to reduce a TIPS shunt in six patients. This method has two main limitations: the first is the inferior patency of PET-covered stents versus PTFE-covered stents and the second is that the method leaves a conduit that is not adjustable. Another technique, which was first reported in 2004 (14) and then corroborated by others (15,16) and modified in a recent report (17), involved the deployment of a balloon-expandable stent and a stentgraft in parallel within the TIPS. The balloon-expandable stent was deployed at the cephalic end of the stentgraft, allowing the end of the stent to remain exposed for future access to the lumen should further decrease in shunt flow be desired. In that report (17), three stent-graft models were examined ex vivo and it was demon-

5 Volume 20 Number 7 Kroma et al 985 strated that only the Wallgraft showed a maintained preferable convex circular or oval cross-section at its waist when it was extrinsically compressed by the balloon-expandable stent. The other stent-grafts exhibited infolding and unpredictable narrowing of the shunt. Even though this method offers bidirectional adjustable TIPS flow reduction, it has the same limitation of the inferior patency of the PET-covered stent by comparison with PTFEcovered stent. Stents covered with PTFE have shown promising long-term patency without an increase in encephalopathy (18) compared with previous methods. Quaretti et al (19) described a PTFEcovered balloon-expandable stent that was placed within the preexisting TIPS and formed into an hourglass shape through strategic balloon dilations distal and proximal to the point of desired narrowing, thereby accomplishing rapid change in the portosystemic gradient. However, the method was technically challenging: the technique required inflation of the balloon-mounted stent while still partially constrained in the delivery sheath. The sheath was then withdrawn and the proximal portion was inflated. Finally, a third balloon inflation was performed to create the hourglass configuration. Weintraub et al (8) used an adjustable PTFE reducing stent constructed with a Wallstent constrained by a 39-mm Atrium PTFE balloon-expandable stent in an hourglass shape. Their technique (8) is very similar to ours except for the need for more materials and previous manipulation, which is unnecessary in our technique, as only the Atrium PTFE-covered balloon-expandable stent was used. The icast stent is a balloon-expandable covered stent that inflates at the edges, first resulting in an hourglass shape; this specific unique feature makes it suitable for TIPS reduction (Fig 2). The difficulty encountered during our procedure was the instability of the covered stent manifested by the slight proximal migration of the covered stent within the TIPS after deployment. This instability was discovered when attempts to withdraw the balloon from the partially inflated covered stent were made. Two suggested reasons for the instability are the balloon catching at the narrow waist of Figure 2. On-table image of partially inflated icast PTFE-covered stent (a) demonstrates an ideal hourglass shape of the stent (b) compared with a less-than-ideal hourglass configuration of another partially inflated PTFE-covered stent (c,d). (Available in color online at the partially inflated covered stent and the lack of sufficient friction between the icast and Viatorr stents. The instability was overcome by further dilation of the covered stent to widen the waist, followed by deployment of an overlapping stent and/or angioplasty at the edges of the covered stent to further seal it with the Viatorr stentgraft. The percentage of TIPS diameter reduction needed for an optimal result is different among patients. The icast covered stent allows for gradual inflation if recurrent ascites, variceal bleeding, or other sequelae of portal hypertension manifest after the procedure. Despite the increase in the portosystemic gradient to greater than the accepted threshold of 12 mm Hg, none of our patients experienced recurrence of variceal bleeding and only one patient showed a temporary reaccumulation of ascites, suggesting that a 12 mm Hg target is not universally valid. The lack of symptom recurrence also supports the use of TIPS reduction rather than occlusion, which can result in fatal consequences. Although TIPS creation can be lifeprolonging, the prognosis of patients who require a TIPS remains grim and the prognosis of those who require a TIPS reduction is even worse. In this case series, all patients who did not undergo transplantation died within 5 months of the TIPS reduction. The only patient who had a favorable long-

6 986 TIPS Reduction with Adjustable Covered Balloon-expandable Stent July 2009 JVIR term outcome was the one who received a transplant after TIPS reduction. The other patients were not transplantation candidates and therefore had no good treatment options. None of the deaths were the result of complications from the TIPS reduction procedures. The data are insufficient to establish optimal patient selection criteria at this time. The number of patients who undergo TIPS reduction is too small to allow analysis of the impact of the procedure on patient survival, but the benefit appears modest unless the procedure is performed as a bridge to transplantation. References 1. LaBerge JM, Somberg KA, Lake JR, et al. Two-year outcome following transjugular intrahepatic portosystemic shunt for variceal bleeding: results in 90 patients. Gastroenterology 1995; 108: Bilbao JI, Quiroga J, Herrero JI, et al. Transjugular intrahepatic portosystemic shunt (TIPS): current status and future possibilities. Cardiovasc Intervent Radiol 2002; 25: Otal P, Smayra T, Bureau C, et al. Preliminary results of a new expanded polytetrafluoroethylene-covered stentgraft for transjugular intrahepatic portosystemic shunt procedures. AJR Am J Roentgenol 2002; 178: Haskal ZJ, Middlebrook MR. Creation of a stenotic stent to reduce flow through a transjugular intrahepatic portosystemic shunt. J Vasc Interv Radiol 1994; 5: Gerbes AL, Waggershauser T, Holl J, et al. Experiences with novel techniques for reduction of stent flow in transjugular intrahepatic portosystemic shunts. J Gastroenterol 1998; 36: Somberg KA, Riegler JL, LaBerge JM, et al. Hepatic encephalopathy after transjugular intrahepatic portosystemic shunts: incidence and risk factors. Am J Gastroenterol 1995; 90: Butterworth RF. Complications of cirrhosis III: hepatic encephalopathy. J Hepatol 2000; 32(suppl): Weintraub J, Mobley DG, Weiss ME, Swanson E, Kothary N. A novel endovascular adjustable polytetrafluoroethylene covered stent for the management of hepatic encephalopathy after transjugular intrahepatic portosystemic shunt. J Vasc Interv Radiol 2007; 18: Paz-Fumagalli R, Crain MR, Mewissen MW, Varma RR. Fatal hemodynamic consequences of therapeutic closure of a transjugular intrahepatic portosystemic shunt. J Vasc Interv Radiol 1994; 5: Forauer AR, McLean GK. Transjugular intrahepatic portosystemic shunt constraining stent for the treatment of refractory postprocedural encephalopathy: a simple design utilizing a Palmaz stent and Wallstent. J Vasc Interv Radiol 1998; 9: Madoff DC, Perez-Young IV, Skolkin MD, Toombs BD. Management of TIPS-related refractory hepatic encephalopathy with reduced Wallgraft endoprostheses. J Vasc Interv Radiol 2003; 14: Haskal ZJ, Brennecke LH. Transjugular intrahepatic portosystemic shunt formed with polyethylene terephthalatecovered stent: experimental evaluation in pigs. Radiology 1999; 213: Jacquier A, Vidal V, Monnet O, et al. A modified procedure for transjugular intrahepatic portosystemic shunt flow reduction. J Vasc Interv Radiol 2006; 17: Saket RR, Sze DY, Razavi MK, et al. TIPS reduction with use of stents or stent-grafts. J Vasc Interv Radiol 2004; 15: Holden A, Ng R, Gane E, Hill A, McCall J. A technique for controlled partial closure of a transjugular intrahepatic portosystemic shunt tract in a patient with hepatic encephalopathy. J Vasc Interv Radiol 2006; 17: Maleux G, Heye S, Verslype C, Nevens F. Management of transjugular intrahepatic portosystemic shunt-induced refractory hepatic encephalopathy with the parallel technique: results of a clinical follow up study. J Vasc Interv Radiol 2007; 18: Sze DY, Hwang GL, Kao JS, et al. Bidirectionally adjustable TIPS reduction by parallel stent and stent-graft deployment. J Vasc Interv Radiol 2008; 19: Barrio J, Ripoll C, Banares R, et al. Comparison of transjugular intrahepatic portosystemic shunt dysfunction in PTFE-covered stent-grafts versus bare stents. Eur J Radiol 2005; 55: Quaretti P, Michieletti E, Rossi S. Successful treatment of TIPS-induced hepatic failure with an hourglass stentgraft: a simple new technique for reducing shunt flow. J Vasc Interv Radiol 2001; 12: