Polytetrafluoroethylene-covered Stent Research Articles

Transjugular Intrahepatic Portosystemic Shunt: Devices Evolution, Technical Tips and Future Perspectives

Portal hypertension (PH) constitutes a pivotal factor in the progression of cirrhosis, giving rise to severe complications and a diminished survival rate. The transjugular intrahepatic portosystemic shunt (TIPS) procedure has undergone significant evolution, with advancements in stent technology assuming a central role in managing PH-related complications. This review aims to outline the progression of TIPS and emphasizes the significant influence of stent advancement on its effectiveness. Initially, the use of bare metal stents (BMSs) was limited due to frequent dysfunction. However, the advent of expanding polytetrafluoroethylene-covered stent grafts (ePTFE-SGs) heralded a transformative era, greatly enhancing patency rates. Further innovation culminated in the creation of ePTFE-SGs with controlled expansion, enabling precise adjustment of TIPS diameters. Comparative analyses demonstrated the superiority of ePTFE-SGs over BMSs, resulting in improved patency, fewer complications, and higher survival rates. Additional technical findings highlight the importance of central stent placement and adequate stent length, as well as the use of smaller calibers to reduce the risk of shunt-related complications. However, improving TIPS through technical means alone is inadequate for optimizing patient outcomes. An extensive understanding of hemodynamic, cardiac, and systemic factors is required to predict outcomes and tailor a personalized approach. Looking forward, the ongoing progress in SG technology, paired with the control of clinical factors that can impact outcomes, holds the promise of reshaping the management of PH-related complications in cirrhosis.

Technique and early results of percutaneous femoropopliteal bypass with stent graft

ObjectiveWe describe the technique and early results of lower extremity revascularization with total percutaneous bypass using extravascular placement of a stent graft (percutaneous prosthetic bypass). MethodsPatients with severe chronic limb threatening ischemia for whom open or endoluminal repair was either not feasible and or had failed were selected for a pilot study using percutaneous prosthetic bypass. The procedure requires placement of three introducer sheaths in the contralateral common femoral artery, and the ipsilateral proximal and distal superficial femoral arteries (SFAs). A guidewire is placed from the contralateral sheath to the ipsilateral popliteal artery via the two ipsilateral sheaths. Two self-expanding polytetrafluoroethylene-covered stents are then placed from the proximal SFA to the distal SFA. ResultsA total of 30 bypasses were performed in 28 patients aged 71 ± 3 years. Of the 28 patients, 16 had severe claudication (Rutherford class 3; 53%) and 14 had critical ischemia (Rutherford class 4-6; 47%). The early results were excellent, with no deaths and one occlusion successfully treated with thrombolysis. No other complications requiring reintervention occurred. The mean follow-up was 25.4 months (range, 3-36 months). The 12- and 36-month Kaplan-Meier survival curve was 100% and 81%, respectively. The primary patency, secondary patency, and freedom from amputation rates were 75% and 75%, 78% and 75%, and 100% and 91%, respectively. ConclusionsFor patients with long lesions and/or failed endovascular treatment, the described technique offers the advantage of a total percutaneous procedure with acceptable early results. If these favorable outcomes are confirmed in larger series with longer follow-up, percutaneous extravascular bypass of the SFA will represent a complementary tool for infrainguinal arterial repair.

Transjugular Intrahepatic Portosystemic Shunt

Transjugular intrahepatic portosystemic shunt (TIPS) is now a well established percutaneous means of decreasing portal hypertension. The major clinical indications for transjugular intrahepatic portosystemic shunt are refractory variceal hemorrhage and refractory ascites. The shunt itself is created by placing a stent between the portal vein and the hepatic vein. The resultant shunting of portal venous flow to the systemic circulation helps reduce the portosystemic gradient and alleviate bleeding and ascites without changing the extrahepatic anatomy. History and Development The transjugular intrahepatic portosystemic shunt was initially described in 1969, originally by prolonged balloon dilation of a percutaneously created tract between the portal and hepatic veins. Unfortunately, short patency of the track remained a major clinical hurdle to its widespread use. The development of balloon expandable metallic stents and the subsequent introduction of flexible bare-metal stents helped improve patency rates. Intimal hyperplasia within the stent, especially at the hepatic venous end, required frequent secondary interventions such as balloon dilation and re-stenting. Early thrombosis was felt to be secondary to placing the transjugular intrahepatic portosystemic shunt across a major bile duct. Advances in stent technology and the introduction of polytetrafluoroethylene-covered stents over a decade ago has led to further increase in clinical patency and improved long-term results with TIPS.

Potential Benefits of Underdilation of 8-mm Covered Stent in Transjugular Intrahepatic Portosystemic Shunt Creation.

INTRODUCTION:Hepatic encephalopathy (HE) is a major complication of transjugular intrahepatic portosystemic shunt (TIPS) creation. This study was aimed to determine whether underdilated TIPS with 8-mm polytetrafluoroethylene-covered stents could reduce the risk of HE and liver damage yet maintain clinical and hemodynamic efficacy.METHODS:This retrospective case-controlled study included 134 patients treated with TIPS from March 2017 to November 2019. All the TIPS procedures were created using 8-mm covered stents, and according to the diameter of expansion balloon catheters, the patients were divided into 2 groups, an underdilated group (6-mm balloon catheter, n = 73) and a control group (8-mm balloon catheter, n = 61).RESULTS:The Kaplan-Meier analysis indicated that the cumulative incidence of overt HE in the underdilated group was significantly lower than that in the control group (11.0% vs 29.5%, log rank P = 0.007), but no statistical differences were found toward variceal rebleeding, shunt dysfunction, and survival between groups. In multivariate analysis, the independent risk factors for overt HE were identified as age (hazard ratio [HR] = 1.036, 95% confidence interval [CI] = 1.003–1.069, P = 0.032), Child-Pugh score (HR = 1.519, 95% CI = 1.212–1.905, P < 0.001), and group assignment (HR = 0.291, 95% CI = 0.125–0.674, P = 0.004).DISCUSSION:Underdilated TIPS with 8-mm polytetrafluoroethylene-covered stents could reduce the risk of HE and liver function impairment compared with completely dilated TIPS, but not increase the risk of variceal rebleeding, shunt dysfunction, and death.

Prognosis of patients undergoing salvage TIPS is still poor in the preemptive TIPS era

BackgroundSalvage transjugular intrahepatic portosystemic shunts (TIPS) are associated with poor prognosis, especially in patients with Child-Pugh C cirrhosis. Since preemptive TIPS improved prophylaxis of variceal bleeding in those patients, recourse to salvage TIPS may now affect patients with a better prognosis. AimTo assess the impact of the preemptive TIPS policy on outcomes after salvage TIPS placement. MethodsWe conducted a retrospective monocentric study on cirrhotic patients undergoing salvage TIPS with polytetrafluoroethylene-covered stents from 2002 to 2017 (period 1 until February 2011; period 2 after the preemptive TIPS policy in March 2011). The primary endpoint was one-year transplant-free survival. ResultsWe included 106 patients (period 1/2 = 53/53 patients, male gender 82%, age 54 ± 9 years, alcoholic cirrhosis 70%, Child-Pugh score B/C 94%). One-year transplant-free survival was 46.0% during period 1 compared to 40.2% during period 2 (p = 0.65). Amongst 61 patients with history of variceal bleeding, 32 (52.5%) had an inadequate secondary prophylaxis, including 19 (59.4%) with a previous indication of preemptive TIPS. One-year transplant-free survival was 33.2% if inadequate secondary prophylaxis vs 65.2% if adequate (p = 0.008). Independent factors associated with survival were a lower Child-Pugh or MELD score, infection, failure to control bleeding, and hepatic encephalopathy after TIPS. ConclusionPrognosis after salvage TIPS remained poor in our series. Optimizing secondary prophylaxis, including preemptive TIPS placement, should be the main concern to improve prognosis.

Portosystemic shunts versus endoscopic intervention with or without medical treatment for prevention of rebleeding in people with cirrhosis.

Portosystemic shunts versus endoscopic intervention with or without medical treatment for prevention of rebleeding in people with cirrhosis.

Clinical and procedure characteristics in patients treated with polytetrafluoroethylene-covered stents after coronary perforation: a CIRC-8U multicenter registry and literature review.

This study aimed at identifying the clinical characteristics and in-hospital outcomes of patients treated with polytetrafluorethylene (PTFE)-covered stents after coronary interventions in a multicenter registry. Subjects with coronary artery perforation were selected from 31,262 consecutive patients who underwent coronary interventions in the hospital registries. Subjects were divided into two groups: those with a PTFE-covered stent implantation and those without a PTFE-covered stent implantation. Clinical characteristics and in-hospital outcomes were compared between the two groups. Data for 82 consecutive coronary perforations (15 PTFE-covered stents and 67 non-PTFE-covered stents) were extracted from each hospital registry. The PTFE-covered stent group had a higher prevalence of perforations due to pre-dilatation before stenting or post-dilatation after stenting (80% vs. 10.4%; p < 0.001), more Ellis classification III perforations (66.6% vs. 28.4%; p = 0.019), longer perforation to hemostasis time (74min vs. 10min; p < 0.001), lower hemostatic success rates (73.3% vs. 94.0%; p = 0.015), and higher in-hospital mortality (26.7% vs. 6.0%; p = 0.015) than the non-PTFE-covered stent group. Although the prevalence of intravascular ultrasound (IVUS) usage was high during coronary interventions (86.7%), IVUS was performed in less than half the cases just before coronary perforations (47%) in the PTFE-covered stent group. Patients requiring PTFE-covered stents are more likely to be observed after balloon dilatation before or after stenting and have a poor prognosis. Careful coronary intervention is needed when IVUS image acquisition is not achieved in addition to proper evaluation of IVUS. Furthermore, if coronary artery perforation occurs, it is important to determine the need for a prompt PTFE-covered stent.

Comparison of the curative effect of transjugular intrahepatic portosystemic shunt with expanded polytetrafluoroethylene-covered stent and drug combined with gastroscopy as the secondary prevention of esophageal -gastric variceal bleeding in portal hypertension

Objective: To compare the clinical efficacy of transjugular intrahepatic portosystemic shunt (TIPS) with expanded polytetrafluoroethylene (ePTFE)-covered stent and drug combined with gastroscopy as the secondary prevention of esophageal-gastric variceal bleeding in portal hypertension. Methods: Patients with esophageal-gastric variceal bleeding who received TIPS treatment (ePTFE covered stent) or gastroscopy for the first time as the secondary prevention for portal hypertension at Nanfang Hospital of Southern Medical University through March to July 2017 were selected. One year after the operation, liver function changes, ascites remission rates, incidence of hepatic encephalopathy, re-bleeding rate, average hospitalization frequency and expenses, survival time, as well as the TIPS patency conditions were analyzed in the two groups of patients. 2 test, Kaplan-Meier method and Mann-Whitney U test were used to analyze the data. Results: There were 74 and 66 cases in the TIPS and the drug combined gastroscopy group and the follow-up duration (14.57 ± 0.79) was 12-16 months. One year after surgery, the remission rate of ascites in the TIPS group was higher 57.1% (32/56) than that of the drug combined gastroscopy group (0), and the difference was statistically significant (χ(2) = 2 = 36.73, P < 0.01). The cumulative incidence of hepatic encephalopathy at 1, 3, 6, and 12 months after surgery in the TIPS group was 32.4% (24/74), 37.8% (28/74), 40.5% (30/74), and 40.5% (30/74), respectively. The cumulative incidence of hepatic encephalopathy in the drug combined gastroscopy group was 3.0% (2/66), 3.0% (2/66), 3.0% (2/66), and 6.1% (4/66), respectively. Kaplan-Meier analysis showed that the cumulative incidence of hepatic encephalopathy in the TIPS group was higher than that of the drug combined gastroscopy group (χ(2) = 11.29, P < 0.01). The incidence of severe hepatic encephalopathy ( grade III to IV) at 1, 3, 6, and 12 months after surgery in the TIPS group was 2.7% (2/74), 0, 0, and 0, respectively. The incidence of severe hepatic encephalopathy in drug combined gastroscopy group was 0, and there was no statistically significant difference in development of hepatic encephalopathy between the two groups (P > 0.05). The re-bleeding rates of TIPS group and drug combined gastroscopy group were 0 and 27.3% (18/66), respectively, and the difference was statistically significant (χ(2) = 22.42, P < 0.01). There was no death reported during the follow-up period between both groups. The hospitalization frequency times (1.45 ± 0.80) in TIPS group was lower than that of the drug combined gastroscopy group times (3.24 ± 1.80), and the difference was statistically significant (U = -4.52, P < 0.01). Conclusion: In the prevention of esophageal-gastric variceal bleeding, TIPS (ePTFE-covered stent) treatment has the advantages of reducing re-bleeding rate, high ascites remission rate and hospitalizations frequency. In addition, patients treated with TIPS have a higher incidence of hepatic encephalopathy than that of drugs combined with gastroscopy. However, TIPS did not exacerbate the incidence of hepatic encephalopathy, and there was no significant difference in the 1-year survival rate after TIPS and drugs combined with gastroscopy treatment.

A Propensity Score-Matched Comparison of Polytetrafluoroethylene-Covered Stents Versus Bare-Metal Stents in the Kissing Conformation for the Treatment of Aortoiliac Arterial Obstructive Disease

The objective was to compare early and midterm outcomes of polytetrafluoroethylene-covered stents (CSs) vs bare-metal stents (BMSs) used in the kissing conformation for the treatment of aortoiliac arterial obstructive disease.

Hospital readmission following transjugular intrahepatic portosystemic shunt: a 14-year single-center experience.

BackgroundPlacement of a transjugular intrahepatic portosystemic shunt (TIPS) is a relatively common procedure used to treat complications of portal hypertension. However, only limited data exist regarding the hospital-readmission rate after TIPS placement and no studies have addressed the causes of hospital readmission. We therefore sought to identify the 30-day hospital-readmission rate after TIPS placement at our institution and to determine potential causes and predictors of readmission.MethodsWe reviewed our electronic medical-records system at our institution between 2004 and 2017 to identify patients who had undergone primary TIPS placement with polytetrafluoroethylene-covered stents and to determine the 30-day readmission rate among these patients. A series of univariable logistic-regression models were fit to assess potential predictors of 30-day readmission.ResultsA total of 566 patients were included in the analysis. The 30-day readmission rate after TIPS placement was 36%. The most common causes for readmission were confusion (48%), infection (15%), bleeding (11%), and fluid overload (7%). A higher Model for End-Stage Liver Disease (MELD) score corresponded with a higher rate of readmission (odds ratio associated with each 1-unit increase in MELD score: 1.06; 95% confidence interval: 1.02–1.09; P = 0.001). Other potential predictors, including indication for TIPS placement, were not significantly associated with a higher readmission rate.ConclusionsThe 30-day readmission rate after TIPS placement with covered stents is high, with nearly half of these readmissions due to hepatic encephalopathy—a known complication of TIPS placement. Novel interventions to help reduce the TIPS readmission rate should be prioritized in future research.

2224 A Rare Complication of Post-TIPS Related Acute Cholecystitis

INTRODUCTION: Amongst the well documented TIPS-related biliary complications, there has been no reported case of acute cholecystitis. Multiple multicenter RCT comparing TIPS to large volume paracentesis reported better control of ascites, lower diuretic doses or cessation of diuretics in approximately 75% of the patients. Biliary related complications include biliary venous fistulas, biloma or biliary occlusion secondary to biliary compression. This may be the first reported case of Post TIPS acute cholecystitis. CASE DESCRIPTION/METHODS: 67-year-old white male with end-stage NASH cirrhosis was hospitalized 6 months ago for diuretic-resistant ascites. Prior to admission, he has required weekly large volume paracentesis. While hospitalized, he underwent large-volume paracentesis and was treated for acute urinary tract infection. TIPS was placed two weeks post discharged and ascites improved. Three days later while undergoing further evaluation, a liver ultrasound showed gall bladder wall thickening and gall stones, suggestive of acute cholecystitis with cholelithiasis. He subsequently developed severe pancytopenia and worsening liver function test. A percutaneous cholecystostomy tube was placed for gall bladder decompression along with a 14-day course of IV antibiotics. He later developed Choledocholithiasis and required ERCP and cholangioscopy. Multiple stones were extracted from the bile duct and complete fibrosis of the cystic duct was noted. The patient required multiple hospitalizations since then, frequent paracentesis and treatment for SBP. He recently underwent OLT with cholecystectomy which was technically challenging. DISCUSSION: TIPS insertion has been established as an effective second-line treatment for refractory ascites. There are 3 documented category of TIPS complications; technical, portosystemic and unique shunt related but no known reported case of acute cholecystitis. Hepatic encephalopathy occurs in approximately 30% of patients, early thrombosis or delayed shunt stenosis occurred in 22- 50% of patients prior to the development of polytetrafluoroethylene-covered stents. The technical intricacy of this intervention poses a potential risk, and morbidity rates as high as 20%. A broad understanding of the uncommon and unique complications can potentially decrease post-op-related complications especially in a patient undergoing OLT It is necessary for clinicians who perform this procedure to be aware of the clinical spectrum of TIPS-related complications and their management.

Ascites control by TIPS is more successful in patients with a lower paracentesis frequency and is associated with improved survival.

Background & AimsRefractory ascites is the main reason for the implantation of a transjugular intrahepatic portosystemic shunt (TIPS) in liver cirrhosis, but ascites control by TIPS fails in a relevant proportion of cases. Here, we investigated whether routine parameters pre-TIPS can predict persistent ascites after TIPS implantation and whether persistent ascites predicts long-term clinical outcome.MethodsA detailed retrospective analysis of 128 patients receiving expanded polytetrafluoroethylene-covered stents for the treatment of refractory ascites was performed. Persistent ascites post-TIPS was defined as the prolonged need for paracentesis >3 months after TIPS. The influence of demographics, laboratory results, pre-TIPS heart and liver ultrasound results, and invasive hemodynamic parameters on persistent ascites was evaluated by univariable and multivariable logistic regression. Predictors of the composite endpoint liver transplantation/death were analyzed using a multivariable Cox regression.ResultsAscites control post-TIPS was achieved in 95/128 patients (74%), whereas ascites remained persistent in 33/128 cases (26%). On multivariable analysis, a lower paracentesis frequency pre-TIPS (odds ratio 1.672; 95% CI 1.253–2.355) and lower baseline creatinine levels (odds ratio 2.640; CI 1.201–6.607) were associated with ascites control. Patients with persistent ascites post-TIPS had and impaired transplant-free survival (median 10.0 vs. 25.8 months), for which persistent ascites was the only independent predictor (hazard ratio 5.654; CI 3.019–10.59).ConclusionTIPS-placement in patients with lower paracentesis frequency and creatinine levels is associated with superior ascites control. Thus, TIPS implantation should be considered in moderate decompensation and not as a last resort. Persistent ascites post-TIPS seems to be the only predictor of liver transplantation and death.Lay summaryThe insertion of a transjugular intrahepatic portosystemic shunt (TIPS) in patients with refractory ascites should be considered in patients with moderate decompensation and not as a last resort, as lower paracentesis frequency and creatinine levels pre-TIPS are associated with superior ascites control. In turn, failure to control ascites seems to be the only predictor of liver transplantation and death.

Edge restenosis of a polytetrafluoroethylene-covered stent in the superficial femoral artery: insights from an imaging assessment with an electronic high-resolution angioscope

Edge restenosis of a polytetrafluoroethylene-covered stent in the superficial femoral artery: insights from an imaging assessment with an electronic high-resolution angioscope

AN ALTERNATIVE WAY TO TREAT ILIAC ANEURYSM

Isolated iliac aneurysms or combined with aortic aneurysms can be treated through implantation of three balloon expandable polytetrafluoroethylene-covered stents in order to create a new iliac bifurcation. We present nine patients, unfit for open surgery and anatomically non suitable for

Outcome after new generation single-layer polytetrafluoroethylene-covered stent implantation for the treatment of coronary artery perforation.

Coronary artery perforation (CAP) is a rare but severe complication during percutaneous coronary intervention (PCI). Implantation of covered stents (CS) represents a potentially life-saving treatment. Concerns exist regarding limited efficacy and high stent thrombosis (ST) rates related to early generation CS. The aim of this study was to evaluate angiographic and clinical outcomes of patients with CAP treated with a new generation single-layer polytetrafluoroethylene (PTFE)-CS. Between May 2013 and November 2017, we identified a total of 61 patients who underwent implantation of 71 single layer PTFE-CS after CAP. We analyzed angiographic results at follow up (including binary angiographic restenosis [BAR] and late-lumen-loss [LLL]) and clinical outcomes in hospital and at follow up, including target lesion revascularization (TLR), cardiovascular-, and all-cause mortality, myocardial infarction (MI) and stent thrombosis (ST). Procedural success was achieved in all but two patients (96.7%). Procedure related MI, occurred in 19 cases (31.1%), in hospital death occurred in five cases (8.2%). At follow-up, TLR occurred in 11 cases (18.0%), two patients (3.3%) died from non-cardiovascular cause, there was no case of MI or ST. In this retrospective analysis, implantation of a new generation PTFE-CS, for the treatment of CAP showed high technical success rates. Although, periprocedural MI-and in-hospital-death rates remain not inconsiderable, new generation PTFE-CS showed favorable angiographic and clinical efficacy and high safety profile, especially with regard to thrombotic events.

Long-term Results of Endovascular Treatment of TASC C and D Aortoiliac Occlusive Disease with Expanded Polytetrafluoroethylene Stent Graft

The aim of this study is to retrospectively analyze the early and long-term outcomes of endovascular treatment of Trans-Atlantic Inter-Society Consensus II class C and D (TASC II) aortoiliac occlusive disease with an expanded polytetrafluoroethylene-covered stent graft. Between January 2006 and November 2017, 61 patients (53 males, 8 females), with symptomatic aortoiliac stenotic and/or occlusive disease, were treated with VIABAHN (W.L. Gore and Associates, Flagstaff, Ariz) at 2 University medical centers. The morphology of the lesions was evaluated and classified by contrast-enhanced computed tomography angiography. Demographic data, operation details, and postoperative outcomes were collected. Follow-up data were analyzed by a life-table analysis (Kaplan-Meier test). Mean age of the patients was 64.89±10.77years (range 44-89). Thirty-seven patients (60.7%) presented with severe claudication (Rutherford 3), whereas 21 (34.4%) were in Rutherford class 4 and the remaining 3 patients (4.9%) suffered from necrotic lesions (Rutherford 5/6). Fifty-six patients were smokers (91.8%), 38 (62.3%) had hypertension, 23 (37.7%) had coronary artery disease, 30 (40.2%) had dyslipidemia, 18 (29.5%) had chronic obstructive pulmonary disease, 6 (9.5%) had renal insufficiency (serum creatinine>2.0mg/dL) and 24 (39.3%) had diabetes. Technical success was achieved in 59/61 patients (96.7%) with 16 patients (26.2%) requiring combined percutaneous brachial access to obtain iliac recanalization. Perioperative mortality was 1.6%, whereas postoperative major complications occurred in 2 patients (3.6%). The mean number of VIABAHN placed was 1.77/patient. Mean follow-up was 31.5months (range 1-108) and primary patency at 36 months was 94.9%. Two major amputations of the lower limbs occurred during the follow-up. Open surgery with the aortobifemoral bypass has been the gold standard treatment for complex aortoiliac occlusive disease although complications and mortality still remain significant issues. Our results suggest that endovascular therapy of TASC C and D iliac lesions using the VIABAHN stent graft is feasible, effective, and has good, long-term patency.

Efficacy of Simultaneous Kissing Stent Technique Using Two Polytetrafluoroethylene-Covered Stents for Severe Coronary Perforation Involving Bifurcation

Efficacy of Simultaneous Kissing Stent Technique Using Two Polytetrafluoroethylene-Covered Stents for Severe Coronary Perforation Involving Bifurcation

P4559Outcome after single-layer polytetrafluoroethylene-covered stent implantation for the treatment of coronary artery perforation

P4559Outcome after single-layer polytetrafluoroethylene-covered stent implantation for the treatment of coronary artery perforation

Under-dilated TIPS Associate With Efficacy and Reduced Encephalopathy in a Prospective, Non-randomized Study of Patients With Cirrhosis

Portosystemic encephalopathy (PSE) is a major complication of trans-jugular intrahepatic porto-systemic shunt (TIPS) placement. Most devices are self-expandable polytetrafluoroethylene-covered stent grafts (PTFE-SGs) that are dilated to their nominal diameter (8 or 10mm). We investigated whether PTFE-SGs dilated to a smaller caliber (under-dilated TIPS) reduce PSE yet maintain clinical and hemodynamic efficacy. We also studied whether under-dilated TIPS self-expand to nominal diameter over time. We performed a prospective, non-randomized study of 42 unselected patients with cirrhosis who received under-dilated TIPS (7 and 6 mm) and 53 patients who received PTFE-SGs of 8mm ormore (controls) at referral centers in Italy. After completion of this study, dilation to 6 mm became the standard and 47 patients were included in a validation study. All patients were followed for6months; Doppler ultrasonography was performed 2 weeks and 3 months after TIPS placement and every 6 months thereafter. Stability of PTFE-SG diameter was evaluated by computed tomography analysis of 226 patients with cirrhosis whose stent grafts increased to 6,7, 8, 9, or 10mm. The primary outcomes were incidence of at least 1 episode of PSE grade 2 or higher during follow up, incidence of recurrent variceal hemorrhage or ascites, incidence of shunt dysfunction requiring TIPS recanalization, and reduction in porto-caval pressure gradient. PSE developed in a significantly lower proportion of patients with under-dilated TIPS (27%) than controls (54%) during the first year after the procedure (P= .015), but the proportions ofpatients with recurrent variceal hemorrhage or ascites did not differ significantly between groups. No TIPS occlusions were observed. These results were confirmed in the validation cohort. In an analysis of self-expansion of stent grafts, during a mean follow-up period of 252days after placement, none of the PTFE-SGs self-expanded to the nominal diameter in hemodynamically relevant sites (such as portal and hepatic vein vascular walls). In prospective, non-randomized study of patients with cirrhosis, we found under-dilation of PTFE-SGs during TIPS placement to be feasible, associated with lower rates of PSE, and effective.

Persistence of gastric or esophageal varices on final angiography increases transjugular intrahepatic portosystemic shunt revision rate after polytetrafluoroethylene-covered stent shunt creation.

To assess the association between final polytetrafluoroethylene (PTFE)-covered stent transjugular intrahepatic portosystemic shunt (TIPS) angiographic parameters and free shunt revision survey. Series of two comparison groups were generated with persistence of varices or not, the 25th, 50th, and 75th percentile as cutoff for each angle and a 15-mm distance as cutoff for distance D. Kaplan Meier free shunt revision curves were then created and compared with Log Rank test. Mean follow-up was 455 days. Thirteen (19.4%) patients had shunt revision. Significant free shunt revision survey difference was found between post-procedural angiographic persistent varices group and the group without varices (P=0.0001). Shunt revision rate at 3, 12 and 24 months was respectively 13%, 29%, and 39% in the group with varices versus 0%, 2.7% and 2.7% in the group without. No difference was found between groups for angles A, B, C and distance D. Persistence of gastric or esophageal varices on final trans-TIPS angiography increases TIPS revision rate after PTFE-covered stent shunt creation whereas geometric parameters have no influence.