Endovascular stent placement in the treatment of upper extremity central venous obstruction in hemodialysis patients

OBJECTIVE: To evaluate the efficacy of stent placement for treating upper extremity central venous obstruction in chronic hemodialysis patients. METHODS AND MATERIAL: Between January 1999 and October 2001, we inserted metallic stents into the upper extremity central veins of 14 patients with shunt dysfunction and/or arm swelling. The indications for stent placement were stenosis or occlusion of the central vein in the upper extremity used for dialysis. Six of the individuals were diagnosed with subclavian vein stenosis, and 5 with brachiocephalic vein stenosis. Of the remaining 3 patients, 2 had subclavian vein occlusion, and 1 had left brachiocephalic vein occlusion. RESULTS: All the stent placement procedures were technically successful, and there were no major complications. Follow-up ranged from 2 weeks to 29 months. The 1-, 3-, 6- and 12-month primary stent patency rates were 92.8, 85.7, 50 and 14.3%, respectively. Repeat interventions, including percutaneous transluminal angioplasty and additional stent placement, were required in 9 patients. The 3-, 6-, 12-month, and 2-year assisted primary stent patency rates were 100, 88.8, 55.5 and 33.3%, respectively. CONCLUSION: Endovascular stent placement is an effective alternative to surgery in patients with shunt dysfunction due to obstruction of an upper extremity central vein. Repeated interventions are usually required to prolong stent patency.     

Venous recanalization by metallic stents after failure of balloon angioplasty or surgery: Four-year experience

Purpose: This retrospective study describes our updated experience in treating venous stenoses and occlusions with metallic endovascular stents. Methods: Gianturco, Palmaz, and Wallstent stents were placed in 55 patients over a 4-year period. Stent sites included the subclavian veins (9), innominate veins (3), superior vena cava (4), inferior vena cava (3), iliac veins (29), femoral veins (5), and portal veins (6). The most common indications for stent placement were malignant stenoses and chronic pelvic venous occlusions. Venoplasty and/or urokinase were used as ancillary therapy. Patients were anticoagulated for 3–6 months. Follow-up included clinical assessment and duplex ultrasound. Results: Lifetable analysis shows 59%, 63%, and 72% primary, primary assisted, and secondary 1-year patency rates, respectively. The 4-year primary patency rates were the same. Duration of patency depended on the venous site. Death was a complication of stent placement in 2 patients and 12 patients died within 6 months after stent placement from primary disease progression. Although early failures were more common in stents placed across occlusions than stenoses, 1-year secondary patency rates were comparable. Primary patency rates were only slightly lower in patients with malignant obstruction than in patients with benign disease. Conclusion: Endovascular stent placement provides a nonsurgical alternative for reestablishment of venous flow and symptomatic relief in patients with benign as well as malignant venous obstruction. Received: 0/00/00/Accepted: 0/00/00     

Shortening and Migration of Wallstents after Stenting of Central Venous Stenoses in Hemodialysis Patients

PURPOSE: To report our results for the placement of central venous stents in patients undergoing hemodialysis. METHODS: Ten Wallstents (Schneider, Bülach, Switzerland) were placed in 10 patients with shunt thrombosis, shunt dysfunction or arm swelling associated with central vein stenosis or occlusion. Technical success, patency and complications were evaluated. RESULTS: Stent deployment was successful in all cases. In seven cases (70%) there was significant delayed stent shortening. In two of these cases there was also stent migration. All these cases required additional stents. Primary patency rates at 6, 12 and 24 months were 66%, 25% and 0. Twenty-three additional procedures (percutaneous transluminal angioplasty or stenting) were required to achieve secondary patency rates at 6, 12 and 24 months of 100%, 75% and 57%. CONCLUSION: Stent placement in the central veins of dialysis patients has a high technical success rate resulting in symptomatic relief and preservation of access. Repeat interventions are required to maintain patency. Significant delayed shortening of the Wallstent occurred in 70% of patients which may have affected the patency rates. Strategies are suggested to avoid this problem.     

Metallic stent placement for treating peripheral outflow lesions in native arteriovenous fistula hemodialysis patients after insufficient balloon dilatation

OBJECTIVE: The purpose of this study was to report our experience with metallic stent placement in the peripheral outflow veins in native arteriovenous fistula (A-V fistula) hemodialysis patients after insufficient balloon dilatation. MATERIALS AND METHODS: During the past 4 years, 12 A-V fistula dialysis patients in our hospital underwent metallic stent placement in the peripheral outflow veins to restore vascular access. The indications for metallic stent placement in our study included (1) recoil stenosis of outflow vein in six patients; (2) outflow venous rupture in two patients and dissection in one patient; and (3) large residual adherent thrombus in outflow aneurysms in three patients with thrombosed (arteriovenous) access. Self-expandable Wallstent or Jostent (Jomed, Abbott Laboratories) of appropriate size (6-10 mm in diameter) was chosen for use in these patients. Kaplan-Meier survival analysis was used to calculate the access patency rates. RESULTS: Twelve patients received stents. Eleven patients (92%) underwent successful dialysis after the procedure. One patient experienced complications due to incorrect positioning of the stent at the anastomotic site, causing flow compromise. The primary patency (+/- standard error) of the vascular access at 3, 6, 12, and 24 months was 92% +/- 8%, 81% +/- 12%, 31% +/- 17%, and 31% +/- 17%, respectively. The secondary patency of the vascular access at 3 months was 92% +/- 8%, and 82% +/- 12% at 6, 12, and 24 months each. CONCLUSION: Metallic stent placement is safe and effective in treating peripheral venous lesions in native A-V fistula hemodialysis patients after unsatisfactory balloon dilatation.     

PTA versus Stent in der femoropoplitealen Strombahn

PURPOSE: To evaluate whether primary stenting is superior to balloon angioplasty (PTA) alone in the treatment of femoropopliteal obstructive disease. MATERIALS AND METHODS: Sixty-two patients, 24 female and 38 male, mean age 67 years (39-87) years, were randomized to PTA alone (n = 37) or balloon angioplasty followed by implantation of Palmaz stents (n = 33). Follow-up included clinical assessment, ankle-brachial index (ABI), color duplex ultrasound at 1, 3, 6 and 12 months after intervention and intravenous angiography at 6 or 12 months. RESULTS: We had four cases of primary PTA failures (10.8%) and no early (< 30 days) thrombosis compared to one primary stent failure (3.0%) and three early thromboses (9.0%) in the stent group. Cumulative primary angiographic patency rates (life-table analysis) for PTA alone were 82% and 72% (6 and 12 months, respectively) compared to 81% and 60% for primary stent placement. The secondary angiographic patency were 97% and 88% for PTA and 88% and 72% for stent implantation, respectively. However, there was no significant difference in patency rates. CONCLUSIONS: Despite fewer primary technical failures, mid-term angiographic and clinical patency were not improved by primary stent placement compared to PTA alone.     

Evaluating Patency Rates of an Ultralow-Porosity Expanded Polytetrafluoroethylene Covered Stent in the Treatment of Venous Stenosis in Arteriovenous Dialysis Circuits

PurposeTo evaluate the efficacy of an ultralow-porosity expanded polytetrafluoroethylene (ePTFE) covered stent in the treatment of autogenous arteriovenous fistula (AVF) and prosthetic arteriovenous graft (AVG) venous outflow stenoses.Materials and MethodsClinical and angiographic outcomes of 20 consecutive patients with arteriovenous dialysis circuits treated with the endoprosthesis were reviewed following institutional review board approval. Patients were followed routinely at 2 months and 6 months after stent placement, or earlier if clinically warranted. The primary endpoint was 2- and 6-month primary treatment area patency. Secondary endpoints included primary circuit patency, primary assisted patency, and secondary patency.ResultsEleven patients with AVFs and nine patients with AVGs were treated successfully with the covered stent. Primary treatment area patency rates were 85% ± 16 at both 2 months and 6 months. Primary circuit patency rates were was 65% ± 21 and 45% ± 22, respectively; primary assisted patency rates were 90% ± 13 and 85% ± 16, respectively; and secondary patency rates were 100% and 90% ± 13, respectively. Of the three cases of lost primary treatment area patency, two developed thrombosis and one developed recurrent stenosis. No significant differences were found between patients with AVFs and AVGs.ConclusionsData from this preliminary study suggests that the ultralow-porosity ePTFE covered stent may be a clinically viable option for treatment of venous outflow stenoses in arteriovenous vascular access circuits.     

Prospective,Multicenter Clinical Study of the Covera Vascular Covered Stent in the Treatment of Stenosis at the Graft-Vein Anastomosis of Dysfunctional Hemodialysis Access Grafts

PurposeTo study the use of the self-expanding Covera covered stent for the treatment of stenotic lesions at the venous anastomosis of hemodialysis arteriovenous grafts (AVGs).Materials and MethodsA total of 110 patients with AVG venous anastomotic stenosis of ≥50% and access dysfunction were treated at 14 centers in the United States using percutaneous transluminal angioplasty followed by covered stent placement. The primary end points were 30-day safety and 6-month target lesion primary patency (TLPP). The secondary measures included access circuit primary patency, circuit cumulative patency, and the number of reinterventions through 24 months.ResultsFreedom from a primary safety event at 30 days was 96.4% while the 6-month TLPP rate was 70.3%. Seventy-five patients completed 24-month follow-up (68.2%). The TLPP rates were 54.2% at 365 days and 36.9% at 730 days while the access circuit primary patency rates were 16.7% at 365 days and 7.8% at 730 days (Kaplan-Meier analysis). The access circuit cumulative patency rates were 85.4% at 12 months and 73.6% at 24 months. The number of reinterventions to maintain the patency of the access circuit was 3.6 ± 3.1 at 24 months (1.6 ± 1.9 at the target lesion).ConclusionsUse of the Covera covered stent for hemodialysis graft-vein anastomotic stenosis provided a safe treatment option with a TLPP rate of 70.3% at 6 months and TLPP and cumulative access circuit patency rates of 36.9% and 73.6% at 2 years.     

Endovascular treatment of atherosclerotic arterial stenoses and occlusions of the supraaortic arteries: mid-term results from a single center analysis

OBJECTIVE: To determine mid-term patency rates after endovascular treatment of supraaortic atherosclerotic arterial stenoses and occlusions using percutaneous transluminal angioplasty (PTA) and stent placement. PATIENTS AND METHODS: During a period of 83 months, 48 patients (18 female, 30 male; mean age 61 years, range 31-82 years) were included into this prospective single-center study. Fifty-five lesions of the brachial and cephalic arteries (subclavian/axillary artery n = 42, innominate artery n = 7, origin common carotid artery n = 6) were treated using PTA (n = 38), PTA plus stent (n = 11) or primary stent placement (n = 6). For anticoagulation, patients received a bolus of heparin (5000 IU) intraarterially during the intervention followed by intravenous application for 24h. At discharge, life-time application of ASA (100mg/day) was initiated. Follow-up protocol included clinical examination, colour-coded duplex ultrasound and intraarterial angiography in case of re-stenosis. RESULTS: PTA and stent placement were technically successful in all patients (100%). No major complications occurred. Of seven patients presenting with total occlusions, six were treated with stent placement. Stent implantation was also performed in all lesions located at the origin of the supraaortic arteries (n = 6). In 38 lesions, the result of PTA was satisfactory. Mean follow-up time is 22 months (range 1-83 months). During follow-up examinations, re-stenoses occurred in 10 cases (at 1 month n = 2, at 6 months n = 2, at 12 months n = 3, at 24 months n = 3). In 9 lesions, re-interventions were performed (PTA n = 7; PTA plus stent n = 2). According to Kaplan-Meier life-table analysis, cumulative primary and primary assisted patency rates are 69.5% (patients at risk n = 15; standard error 9%) and 90.6% (patients at risk n = 16; standard error 6.3%) at 20 months, respectively. CONCLUSIONS: Endovascular treatment of atherosclerotic obstructive disease in brachial and cephalic arteries is a safe procedure showing promising mid-term patency rates.     

经皮球囊血管成形术和经皮支架植入术治疗透析通路中心静脉狭窄的临床效果比较

目的：观察透析通路中心静脉狭窄（CVS）经皮球囊血管成形术（PTA）和经皮支架植入术（PTS）治疗的近中期疗效。 方法：选取2014年10月—2016年10月收治的发生CVS的血液透析患者40例,按治疗方式的不同分为PTA治疗组26例和PTA+PTS治疗组14例。观察两组患者术后疗效及通路管径变化情况;随访术后1、3、6个月透析通路的开放情况及开放时间。 结果：术后相关症状均在1周内改善,治疗后通路直径较治疗前均增宽;PTA治疗组的初级开放时间为（5.17±1.54）个月,高于PTA+PTS治疗组的初级开放时间（3.57±1.71）个月;PTA+PTS治疗组的腔内干预次数为（1.93±0.47）次,高于PTA治疗组的（1.35±0.56）次,差异均有统计学意义。PTA治疗组1、3、6个月的初级开放率分别为96.2%、80.7%、69.2%,辅助初级开放率分别为100%、92.3%、92.3%;PTA+PTS治疗组1、3、6个月的初级开放率分别为92.9%、64.3%、14.3%,辅助初级开放率分别为100%、100%、85.7%。两组的初级开放率和辅助初级开放率差异无统计学意义。 结论：透析通路CVS的治疗首选单纯PTA,当出现PTA抵抗或频繁复发时,可以考虑植入支架。     

Percutaneous transluminal angioplasty (PTA) alone versus PTA with balloon-expandable stent placement for short-segment femoropopliteal artery disease: a metaanalysis of randomized trials

PURPOSE: To evaluate and compare the results of percutaneous transluminal angioplasty (PTA) and stent placement to treat femoropopliteal artery occlusive disease. MATERIALS AND METHODS: Published data of randomized clinical trials comparing the results of PTA and stent placement for femoropopliteal artery occlusive disease were analyzed. Proportions were combined, and the odds ratio (OR) with its 95% CI was used as the effect size estimate. RESULTS: Seven studies published in 1999 or later (614 limbs in 519 patients) were included in this metaanalysis, in which 323 limbs underwent PTA and 291 limbs underwent PTA followed by balloon-expandable stent placement. In the combined results of PTA versus PTA plus stent placement, a significant difference in primary patency at 6 months (OR, 0.47; 95% CI, 0.27-0.84; P < .05) was found, but no significant difference could be found in primary patency at 12 months (OR, 1.27; 95% CI, 0.87-1.86; P > .05) or 24 months (OR, 1.22; 95% CI, 0.81-1.82; P > .05) or in secondary patency at 12 months (OR, 1.34; 95% CI, 0.78-2.30; P > .05). CONCLUSIONS: In the treatment of femoropopliteal artery occlusive disease (< or =10 cm), higher primary patency rates can be expected at 6 months with PTA followed by implantation of balloon-expandable stents versus PTA alone, but PTA with stent placement does not produce better long-term primary results and secondary patency rates than PTA alone.     

Malignant colorectal obstruction treated by means of self-expanding metallic stents: effectiveness before surgery and in palliation

PURPOSE: To determine the effectiveness and safety of metallic stents in the treatment of malignant colorectal obstruction before surgery and for palliation. MATERIALS AND METHODS: Eighty patients with acute malignant colorectal obstruction presumed to be malignant were treated by means of implanting self-expanding metallic stents. RESULTS: Stent placement was successful in 70 of the 80 patients and resolved bowel obstruction in 67 patients (96%). Two patients had colonic perforation and developed peritonitis 18 and 24 hours after stent placement; one patient died as a consequence. Thirty-three patients underwent elective surgery after 7 days +/- 3 (SD; range, 4-10 days), and adequate tumoral coverage and cleansing of the colon were observed in all patients. Stent placement was used as final palliative treatment in another 35 patients. Patient follow-up lasted a mean of 138 days +/- 93 (range, 36-334 days). The survival rate for the palliative group was 55% at 3 months, 44% at 6 months, and 25% at 9 months. The estimated primary stent patency rate was 91% at 3 and 6 months. CONCLUSION: Management of colorectal obstruction by using metallic stents was effective and safe, although colonic perforation is a potential complication. In cases of palliation, the method may obviate palliative colostomy.     

Percutaneous Treatment of Central Venous Stenosis in Hemodialysis Patients: Long-Term Outcomes

The purpose of this study was to evaluate the long-term outcomes of endovascular treatment of central venous stenosis in patients with arteriovenous fistulas (AVFs) for hemodialysis. Five hundred sixty-three patients with AVFs who were referred for a fistulogram were enrolled in this study. Among them, 44 patients showed stenosis (n = 35) or occlusions (n = 9) in the central vein. For the initial treatment, 26 patients underwent percutaneous transluminal angioplasty (PTA) and 15 patients underwent stent placements. Periods between AVF formation and first intervention ranged from 3 to 144 months. Each patient was followed for 14 to 60 months. Procedures were successful in 41 of 44 patients (93.2%). Primary patency rates for PTA at 12 and 36 months were 52.1% and 20.0%, and assisted primary patency rates were 77.8% and 33.3%, respectively. Primary patency rates for stent at 12 and 36 months were 46.7% and 6.7%, and assisted primary patency rates were 60.0% and 20.0%, respectively. Fifteen of 26 patients with PTAs underwent repeated interventions because of restenosis. Fourteen of 15 patients with a stent underwent repeated interventions because of restenosis and combined migration (n = 1) and shortening (n = 6) of the first stent. There was no significant difference in patency between PTAs and stent placement (p > 0.05). Average AVF patency duration was 61.8 months and average number of endovascular treatments was 2.12. In conclusion, endovascular treatments of central venous stenosis could lengthen the available period of AVFs. There was no significant difference in patency between PTAs and stent placement.     

Long-term results of treatment of benign central venous obstructions unrelated to dialysis with expandable Z stents.

PURPOSE: To evaluate long-term patency of self-expanding Z stents for treatment of benign central venous obstructions unrelated to dialysis. MATERIALS AND METHODS: Z stents were placed in 19 patients, (ages 26-72 years) with severe symptomatic obstructions of the superior or inferior venae cavae and their large branches and portal vein caused by surgical or catheter injury (n = 8), fibrosis (n = 5), cirrhosis (n = 3), Budd-Chiari syndrome (n = 2), and extrinsic compression (n = 1). Fourteen patients underwent stent placement primarily, five after local urokinase infusion for superimposed thrombosis. Follow-up was performed with ultrasound and venography. RESULTS: Venous congestive symptoms quickly resolved in all patients after stent placement. The follow-up period was from 1 to 94 months. Twelve patients have died during follow-up from 1 to 37 months although all remained asymptomatic until death. Six patients remain alive, asymptomatic, with patent stents, and with follow-up from 24 to 94 months. Primary patency was 83%, and secondary patency was 100%. One patient with a patent stent at 12 months was lost to follow-up. No stent migrations, perforations, infections, or significant complications occurred. CONCLUSION: Benign central venous obstructions are effectively treated by the placement of self-expandable Z stents. Placed percutaneously into obstructive lesions with a minimum risk, these stents offer long-term durability and patency.     

Subintimal angioplasty of long superficial femoral artery occlusions

PURPOSE: To investigate the value of subintimal angioplasty (SA) and selective stent placement in the treatment of long (> or =15 cm) superficial femoral artery (SFA) occlusions. MATERIALS AND METHODS: During a period of 4.5 years, 67 long SFA occlusions in 61 patients (52 male, 9 female) were intended to be treated with SA, either retrogradely (n = 55) or antegradely (n = 12). Postprocedural medical treatment included aspirin + ticlopidine/clopidogrel (AT/C) combination. In 25 patients warfarin was also given for 3-6 months. Patients were followed up for 1-30 months (mean 12.5 +/- 9.0 months). Hemodynamic patencies were determined with the Kaplan-Meier method, risk factors affecting patency were evaluated with the Cox model, and the patencies of the subgroups were compared with log-rank test. RESULTS: Subintimal recanalization was technically successful in 59 of 67 occlusions. Technical success was 83% in the first 30 procedures, 92% in the last 37, and 100% in the last 29. Forty-six occlusions were treated with SA alone and 13 with SA and stent placement. On an intention-to-treat basis, primary patency at 6 and 12 months was 49% and 22%, respectively, and assisted primary patency at 6 and 12 months was 69% and 57%, respectively. Patency rates were not significantly different in patients with claudication versus critical limb ischemia, or in those treated with SA alone versus SA and stent placement. With the multivariate Cox model, medical treatment with AT/C combination was identified as the only significant risk factor for both primary patency and assisted primary patency. With the Kaplan-Meier analysis, primary and assisted primary patencies were significantly higher in the warfarin group than the AT/C group (P =.0002 and.0001, respectively). CONCLUSION: SA is a simple and safe method with a high technical success rate in the endovascular treatment of long SFA occlusions. Long-term patency rates, however, seem unsatisfactory, despite early reports. Subintimal stent placement provides cumulative patency at least as good as SA alone. Warfarin may significantly improve both primary patency and assisted primary patency after subintimal recanalization, but even with this treatment patency rates are still lower than those reported for bypass surgery. Therefore, in long SFA occlusions, SA is not recommended for claudicants but may be valuable in patients with critical limb ischemia.     

Use of Nitinol Stents Following Recanalization of Central Venous Occlusions in Hemodialysis Patients

Purpose To retrospectively review the patency of endovascular interventions with nitinol stent placement for symptomatic central venous occlusions in hemodialysis patients. Methods A retrospective review of all patients who underwent endovascular interventions for dysfunctional hemodialysis grafts and fistulas was performed from April 2004 to August 2006. A total of 6 patients presented with arm and/or neck and facial swelling and left brachiocephalic vein occlusion. The study group consisted of 3 men and 3 women with a mean age of 79.5 years (SD 11.2 years). Of these 6 patients, 1 had a graft and 5 had fistulas in the left arm. The primary indication for nitinol stent placement was technical failure of angioplasty following successful traversal of occluded central venous segments. Patency was assessed from repeat fistulograms and central venograms performed when patients redeveloped symptoms or were referred for access dysfunction determined by the ultrasound dilution technique. No patients were lost to follow-up. Results Nitinol stent placement to obtain technically successful recanalization of occluded venous segments was initially successful in 5 of 6 patients (83%). In 1 patient, incorrect stent positioning resulted in partial migration to the superior vena cava requiring restenting to prevent further migration. Clinical success was observed in all patients (100%). Over the follow-up period, 2 patients underwent repeat intervention with angioplasty alone. Primary patency was 83.3% (95% CI 0.5–1.2) at 3 months, and 66.7% at 6 and 12 months (0.2–1.1, 0.1–1.2). Secondary patency was 100% at 12 months with 3 patients censored over that time period. Mean primary patency was 10.4 months with a mean follow-up of 12.4 months. No complications related to recanalization of the occluded central venous segments were observed. Conclusion Our initial experience has demonstrated that use of nitinol stents for central venous occlusion in hemodialysis patients is associated with good mid-term patency and may exceed historical observations with prior use of Wallstents.     

Stent Grafts for Central Venous Occlusive Disease in Patients with Ipsilateral Hemodialysis Access

PurposeTo assess long-term outcomes of stent grafts in patients with symptomatic central venous stenoses and occlusions ipsilateral to hemodialysis grafts or fistulas.Materials and MethodsThe study included 52 of 55 consecutive patients with symptomatic stenoses of the central veins draining upper limb dialysis access grafts or fistulas treated with stent grafts. Indications for stent grafts were poor angioplasty results, rapid recurrence, or total occlusion. Endpoints were lesion patency and access patency following intervention. Mean follow-up was 25 months with a median of 24 months and 1.25 additional procedures per patient year. Patency rates were calculated using Kaplan-Meier analysis.ResultsAll stent grafts were successfully deployed. The lesion patency rates at 6, 12, 24, and 36 months after intervention were 60%, 40%, 28%, and 28%. The access patency rates at 6, 12, 24, and 36 months after intervention were 96%, 94%, 85%, and 72%. There was one major complication and no minor complications. In 40 patients (77%), the internal jugular vein confluence was covered by the stent graft. In five patients, the dialysis circuits became occluded, with no clinical sequelae in four; one patient was lost to follow-up. The contralateral brachiocephalic vein was covered in three patients (6%), preventing contralateral access construction in one patient.ConclusionsCentral vein stent graft placement in patients with hemodialysis access is associated with prolonged access patency. Coverage of major vein confluences, which occurred in 83% of the patients in this series, can compromise future access and should be avoided whenever possible by careful technique.     

Outcome of percutaneous transhepatic venoplasty for hepatic venous outflow obstruction after living donor liver transplantation

PURPOSE: To evaluate retrospectively the outcome of percutaneous transhepatic venoplasty of hepatic venous outflow obstruction after living donor liver transplantation (LDLT). MATERIALS AND METHODS: The institutional Human Subjects Research Review Board approved the interventional protocol and the retrospective study, for which informed consent was not required. Before treatment, informed consent was obtained from the patient or the patient's parents in all cases. Of 26 consecutive patients (nine male, 17 female; median age, 9 years) suspected of having hepatic venous outflow obstruction after LDLT, 20 patients confirmed to have anastomotic outflow stenosis at percutaneous hepatic venography and manometry underwent venoplasty. Pressure gradients before and after venoplasty were evaluated by using a paired t test. Patients in whom obstruction recurred during follow-up were re-treated with venoplasty with or without expandable metallic stents. Patency was analyzed by using Kaplan-Meier analysis. RESULTS: The initial balloon venoplasty was technically successful in all 20 patients, all of whom had improved clinical findings. The pressure gradient +/- standard deviation was reduced from 14.6 mg Hg +/- 8.6 to 2.2 mg Hg +/- 2.4 (P < .001). Eleven patients had recurrent obstruction and were treated with balloon venoplasty; one of them underwent stent placement, as well as venoplasty. The primary (event-free) patency and 95% confidence interval (CI) at 3, 12, and 60 months after venoplasty were 0.80 (95% CI: 0.62, 0.98), 0.60 (95% CI: 0.38, 0.81), and 0.60 (95% CI: 0.38, 0.81), respectively. The primary assisted patency, maintained with repeated venoplasty and expandable metallic stents, was 1.00 at 60 months. CONCLUSION: Percutaneous venoplasty is an effective treatment for hepatic venous outflow obstruction after LDLT.     

Initial clinical experience with the 4-F self-expanding XPERT stent system for infrapopliteal treatment of patients with severe claudication and critical limb ischemia

PURPOSE: To evaluate the primary success and short-term patency associated with a new 4-F sheath-compatible self-expanding nitinol stent after failed conventional angioplasty of distal popliteal and infrapopliteal lesions in severe lifestyle-limiting claudication (LLC) and chronic critical limb ischemia (CLI). MATERIALS AND METHODS: Between May 2003 and July 2005, 35 patients with Rutherford category 3-5 disease (16 patients with CLI, 19 patients with LLC) underwent percutaneous transluminal angioplasty (PTA) and stent implantation. Indications for stent placement were residual stenosis, flow-limiting dissections, or elastic recoil after PTA. Before and after the intervention and during the 6-month follow-up, clinical investigation, color-flow and duplex Doppler ultrasonography, and digital subtraction angiography were performed. Technical success, primary patency at 6 months, clinical improvement as defined by Rutherford with clinical and hemodynamic measures, and complications were evaluated. RESULTS: A total of 22 patients underwent distal popliteal artery stent placement and 13 underwent tibioperoneal artery stent placement. Stent implantation was successfully performed in all patients. After stent placement, the primary cumulative patency rate for the study group at 6 months was 82%. The mean resting ankle-brachial index at baseline was 0.50 +/- 0.16 and significantly increased to 0.90 +/- 0.17 at 12-24 hours after intervention and 0.82 +/- 0.24 at latest follow-up (P < .001 for both). The sustained clinical improvement rate was 80% at the 6-month follow-up. The 6-month limb salvage rate regarding major amputation was 100%. The rate of major complications was 17%. CONCLUSIONS: Infrapopliteal application of the new nitinol stent is a safe, feasible, and effective method with good short-term patency rate in the treatment of severe LLC and chronic CLI.     

Long-term Outcome of Percutaneous Interventions for Hepatic Venous Outflow Obstruction after Pediatric Living Donor Liver Transplantation: Experience from a Single Institute

PurposeTo evaluate retrospectively the long-term outcome of percutaneous interventions for hepatic venous outflow obstruction (HVOO) occurring after pediatric living donor liver transplantation (LDLT).Materials and MethodsBetween October 1997 and December 2012, 48 patients (24 boys, 24 girls; median age, 6 y) who had undergone LDLT were confirmed to have HVOO using percutaneous hepatic venography and manometry. All patients underwent percutaneous interventions, including balloon angioplasty with or without stent placement. Technical success, clinical success, patency rates, stent placement, and major complications were evaluated.ResultsTechnical success was achieved in 92 of 93 sessions (99.0%) and in 47 of 48 patients (97.9%), and clinical success was achieved in 41 of 48 patients (85.4%). During the follow-up period (range, 1–182 mo; median, 51.5 mo), 28 patients were treated with a single session of balloon angioplasty, and 20 patients who developed recurrent stenosis were treated with repeated percutaneous interventions. The rates of primary and primary-assisted patency at 1, 3, 5, and 10 years after balloon angioplasty were 64%, 57%, 57%, and 52% (primary patency) and 98%, 95%, 95%, and 95% (primary-assisted patency). Of six patients with stent placement, four had no recurrent HVOO after the stent placement, but two developed recurrent stenosis. The stent migrated to the right atrium in one patient.ConclusionsPercutaneous interventions were effective treatments for HVOO after LDLT.     

Covered Stent Placement for the Treatment of Malignant Superior Vena Cava Syndrome: Is Unilateral Covered Stenting Safe and Effective?

Objective

To evaluate the safety and efficacy of unilateral covered stent placement in patients with malignant superior vena cava (SVC) syndrome.

Materials and Methods

Between October 2008 and November 2012, expanded polytetrafluoroethylene-covered stent placement for malignant SVC syndrome was performed in 40 consecutive patients (35 men and five women; mean age, 61.4 years; range, 35-81 years). All covered stents were unilaterally placed within the SVC or across the venous confluence when needed to relieve venous obstruction and prevent tumor overgrowth, regardless of patency of contralateral brachiocephalic veins.

Results

Stent placement was technically successful in all patients. There were no major complications. Of the 37 patients symptomatic prior to stent placement, 34 (92%) experienced complete symptomatic relief 1-8 days after stent placement. Of the 29 patients who underwent covered stent placement across the venous confluence, nine patients had patent contralateral brachiocephalic veins prior to stent placement. However, no sign of SVC obstruction or contralateral upper extremity venous thrombosis was observed during the follow-up period. Kaplan-Meier analysis revealed median patient survival of 163 days. Stent occlusion occurred in four (10%) of 40 patents. Cumulative stent patency rates at 1, 3, 6, and 12 months were 95%, 92%, 86%, and 86%, respectively.

Conclusion

Unilateral covered stent placement appears to be a safe and effective method for treating malignant SVC syndrome, despite the location of SVC occlusion.