Chronically occluded inferior venae cavae: endovascular treatment

PURPOSE: To report the results of endoluminal recanalization and stent placement in patients with chronic occlusions of the inferior vena cava (IVC). MATERIALS AND METHODS: Seventeen consecutive patients (12 male, five female patients; mean age, 40.6 years; age range, 15-77 years) with chronic IVC occlusions were treated during a 6-year period. The mean duration of symptoms was 32 months. Underlying active malignancy was the cause of occlusion in four patients. Five patients with superimposed acute thrombus underwent catheter-directed thrombolysis prior to IVC recanalization. Clinical patency was defined as absence or improvement of symptoms. Clinical follow-up was supplemented with ultrasonography, vena cavography, or both in 10 patients. RESULTS: Technical success was achieved in 15 (88%) patients. Additional thrombolytic therapy and stent placement was needed in two patients to maintain patency at 4 and 6 months after the procedure. Twelve patients had IVCs that remained patent after a mean follow-up of 19 months for a primary patency rate of 80%. The primary assisted patency rate was 87% (13 of 15). There were four deaths owing to underlying disease 6-21 months after the procedures. There were no procedure-related complications. CONCLUSION: Endoluminal recanalization and stent placement in chronically occluded IVCs has a good intermediate-term outcome and should be considered in patients who have symptoms and who often do not have adequate alternative therapy.     

Short (1-10 cm) superficial femoral artery occlusions: results of treatment with excimer laser angioplasty

Purpose: To evaluate the safety and long-term results after laser angioplasty of short occlusions of the superficial femoral artery (SFA). Methods: In a prospective trial in 312 patients with short occlusions of the SFA excimer laser angioplasty for recanalization was applied. The average occlusion length of the SFA was 7.5 cm (range 1–10 cm). The recanalization attempt was done using either a cross-over technique from the contralateral femoral artery (278 patients), antegrade technique (16 patients) or transpopliteal technique (18 patients). Results: Percutaneous transluminal laser angioplasty (PTLA) produced successful recanalization of the SFA in 286 of 312 patients (91.7%). In 26 patients (8.3%) recanalization was not possible. The reason for the unsuccessful PTLAs was obstructing calcified materialn = 8) which was resistant to laser application. In nine cases obstructing calcifications resulted in positioning of the laser catheter in subintimal tissue or perforation of the SFA. In another four patients there was an aberrant anatomy of the SFA which resulted in a direct vessel injury after advancing the laser catheter. In five patients subintimal recanalization failed. After a follow-up period of 36 months there was a primary, primary assisted and secondary patency rate of 49.2%, 76.5% and 86.3%. Conclusion:Excimer laser angioplasty of short occlusions of the SFA is a feasible procedure with a low failure rate. Long-term results are promising but additional interventions are required in most patients to achieve a patency rate of 86.3% after 3 years. Further studies are needed to compare the clinical outcome of PTLA and PTA in short occlusions of the SFA.     

Subintimal Recanalization of Long Superficial Femoral Artery Occlusions Through the Retrograde Popliteal Approach

Purpose: To investigate the value of the retrograde popliteal artery approach for the percutaneous intentional extraluminal recanalization (PIER) of long superficial femoral artery (SFA) occlusions. Methods: During a period of 17 months, PIER through ultrasound-guided retrograde popliteal artery puncture was performed for 39 long SFA occlusions in 37 patients. In six patients, six additional iliac artery stenoses were also treated via the popliteal approach. Results: The procedure was technically successful in 32 (82%) of 39 SFA occlusions; in 29, lesions were treated with balloon angioplasty alone, and in three, stents were also used. Cumulative patency rate was 66% at 6 months, 62% at 1 year, and 59% at 18 months. Additional iliac artery stenoses were successfully treated in the same session. Complications included two minor hematomas and two SFA ruptures, which required no treatment. Conclusion: PIER through retrograde popliteal puncture is a safe and effective method in the treatment of long femoropopliteal occlusions, with a high technical success, low complication rate and a reasonable short-term patency rate. The technique offers an alternative in cases where standard PIER is unsuccessful or contraindicated.     

Endovascular placement of self-expanding nitinol coil stents for the treatment of femoropopliteal obstructive disease

PURPOSE: To report on a prospective two-center study to evaluate safety and effectiveness of a self-expanding nitinol coil stent in patients with femoropopliteal obstructive disease. MATERIALS AND METHODS: The IntraCoil nitinol stent was used in 37 patients (28 men and nine women; mean age, 62.4 y plus minus 10.7; range, 43-81 y) presenting with high-grade stenoses (n = 23) or short (<3 cm) occlusions (n = 17) of the superficial femoral artery (SFA; n = 33) or popliteal artery (n = 4). Indications for stent placement were significant residual stenosis (>30%) or dissection after angioplasty. Follow-up evaluations with measurement of the Doppler ankle-brachial index (ABI), assessment of Rutherford clinical stage, and color-coded duplex sonography were performed at discharge and 1, 3, 6, 12, and 18 months thereafter. Primary endpoints of the study were immediate technical and clinical success and 1-year patency. RESULTS: Initial technical success was achieved in all patients. In 10 patients (27%), more than one 40-mm-long device had to be implanted for total lesion coverage; in three patients (8.1%), stents were placed in two separate segments of the SFA simultaneously. The total number of stents deployed was 50. Stent placement induced an initial improvement of the ABI from 0.54 plus minus 0.2 to 0.92 plus minus 0.11 (P <.01). Follow-up data for 12 months after treatment are available for 29 of 37 patients (78.4%); mean follow-up is 15.6 months (range, 1-26 mo). Primary patency rates at 6 and 12 months were 97.1% (SE = 2.9) and 86.2% (SE = 6.5). The primary assisted patency rate was 100% at 12 months. CONCLUSION: Endovascular placement of the IntraCoil self-expanding nitinol coil stent for salvage of failed angioplasty in patients with femoropopliteal obstructive disease is an effective and safe procedure with promising mid-term results.     

Treatment of long superficial femoral artery occlusions with excimer laser angioplasty: long-term results after 48 months

Purpose: To evaluate clinical and hemodynamical long-term results after laser angioplasty of long occlusions of the superficial femoral artery (SFA).

Material and Methods: In a prospective trial of 452 patients with long occlusions of the SFA, excimer percutaneous transluminal laser angioplasty (PTLA) for recanalization was applied. The average occlusion length of the SFA was 25.5 cm (range 16-38 cm). The recanalization attempt was done with the crossover technique in 398 patients, in 36 patients with the antegrade technique and in another 18 patients with the transpopliteal technique.

Results: The application of laser angioplasty demonstrated a successful recanalization of the SFA in 386/452 patients (85.5%). Recanalization with PTLA was not possible in 66 patients (14.5%). The main reason for the unsuccessful PTLAs was obstructing calcified material (n=28) resistant to PTLA application. After a follow-up period of 48 months there was a primary, primary-assisted, and secondary patency rate of 22.3%, 40.9%, and 43.2%, respectively.

Conclusion: Laser angioplasty of long occlusions of the SFA is a feasible procedure with a low failure rate. Long-term results are promising, but additional interventions are required in most patients if a patency rate of 43.2% is to be achieved after 4 years.     

Long-Term Results after Placement of Aortic Bifurcation Self-Expanding Stents: 10 Year Mortality,Stent Restenosis,and Distal Disease Progression

Purpose To retrospectively evaluate the 10 year follow-up results in patients who had “kissing” self-expanding stent aortic bifurcation reconstruction. Methods Forty-three patients were treated with “kissing” self-expanding stents for aortoiliac occlusive disease. Early follow-up with clinical and ankle brachial pressure indices (ABPI) was performed at 3, 6, 12, and 24 months and with intra-arterial digital subtraction angiography at 12–24 months; clinical and angiographic follow-up was performed for symptom recurrence up to 10 years after treatment. Retrospective record review was performed to assess mortality, clinical patency, angiographic patency, and secondary assisted patency of both stents and downstream peripheral vessels at 5 and 10 years follow-up. Results The 2 year primary angiographic and secondary assisted stent patencies were 89% and 93%, respectively. At 10 years follow-up in 40 patients the mortality was 38% (due to myocardial infarction, stroke, chronic renal failure, malignancy, and liver failure). At 5 and 10 years follow-up the primary clinical stent patency was 82% and 68%, and the secondary assisted stent patency 93% and 86%, respectively. At 5 and 10 years, the distal vessel patency was 86% and 72%, and the secondary assisted distal vessel patency treated by surgical or endovascular techniques was 94% and 88%, respectively. At 10 years there was no limb loss. Conclusion The long-term (10 year) results of aortic bifurcation arterial self-expanding stent placement in patients with arterial occlusive disease show a 10 year primary stent patency rate of 68% but a secondary assisted patency rate of 86%. In addition there is a high overall mortality due to other cardiovascular causes and the rate of distal disease progression and loss of patency is similar to the loss of stent patency rate.     

Percutaneous Treatment in Iliac Artery Occlusion: Long-Term Results

We evaluated the long-term results of recanalization with primary stenting for patients with long and complex iliac artery occlusions. This was a retrospective nonrandomised study. Between 1995 and 1999, 138 patients underwent recanalization of an occluded iliac artery with subsequent stenting. Patency results were calculated using Kaplan–Meier analysis. The mean length of follow-up was 108 months. Variables affecting primary stent patency such as patient age; stent type and diameter; lesion site, shape, and length; Society of Cardiovascular and Interventional Radiology classification; total runoff score; Fontaine classification; and cardiovascular risk factors were analysed using Breslow test. These variables were then evaluated for their relation to stent patency using Cox proportional hazards test. Technical success was 99%. Primary patency rates were 90% (SE .024), 85% (SE .029), 80% (SE .034), and 68% (SE .052) at 3, 5, 7, and 10 years, respectively. Lesion site (p = 0.022) and stent diameter (p = 0.028) were shown to have a statistically significant influence on primary stent patency. Long-term results of iliac recanalization and stent placement were excellent, without major complications, even in highly complex vascular obstructions. A primary endovascular approach appears to be justified in the majority of patients as a less invasive alternative treatment to surgery. In any case, a first-line interventional approach should be considered in elderly patients or in patients with severe comorbidities.     

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     

Endovascular treatment of stenoses in the superior vena cava syndrome caused by non-tumoral lesions

We report our experience in percutaneous treatment of non-tumoral superior vena cava syndrome (SVCS) between December 1998 and July 2001. During a period of 2.5 years, 9 patients (age range 27–84 years, mean age 50 years) were treated percutaneously for significant non-tumoral SVCS. Symptomatic SVCS were due to dialysis catheters (7), central line (1) and radiation therapy (1). In thrombotic occlusions and severe stenosis, a preliminary in situ thrombolysis was achieved before angioplasty. Patients were followed by echo-Doppler, computed tomography angiography (CTA), magnetic resonance angiography (MRA), or phlebography. Complete recanalization of the veins and immediate resolution of symptomatic SVCS were obtained in all patients, with no procedure-related complication. Thirteen stents were placed in 9 patients with a mean clinical follow-up of 9.1 months (range 2–23 months). One hundred percent patency at 6 months was obtained. Two patients recurred twice and were treated with new stent placement. At 12 months the patency was 67% and assisted patency was 100%. Stent placement in benign symptomatic SVCS is a safe and minimally invasive procedure, with no technical and clinical complications in our experience. It allowed immediate relief of symptoms, and in dialysed patients could provide continued use of hemodialysis access. Close clinical surveillance is mandatory to assess stent patency. Electronic Publication     

Technique and Clinical Outcomes of Combined Stent Placement for Postthrombotic Chronic Total Occlusions of the Iliofemoral Veins

Purpose

To evaluate the technical aspects and early clinical results of combined stent placement for the management of postthrombotic syndrome (PTS) in chronic total occlusions (CTOs) of the iliofemoral veins.

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.     

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.     

Combined Antegrade Femoral Artery and Retrograde Popliteal Artery Recanalization for Chronic Occlusions of the Superficial Femoral Artery

PurposeTo evaluate the efficacy and safety of a dual femoral–popliteal approach in the supine position after failed antegrade recanalization attempts in chronic total occlusion (CTO) of the superficial femoral artery (SFA).Materials and MethodsFrom May 2011 to October 2012, 21 patients underwent dual femoral–popliteal recanalization for CTO of the SFA, with a mean lesion length of 87.4 mm ± 5.8. When contralateral antegrade recanalization of SFA occlusions via the common femoral artery could not be achieved, the occlusions were intrainterventionally accessed by retrograde approach via the popliteal artery, which was punctured anteriorly with gently flexed knee and crus extorsion. When the SFA had been recanalized, further angioplasty and stent placement procedures were completed via the femoral artery.ResultsA technical success rate of 100% (entailing puncture of the popliteal artery and SFA recanalization) was achieved, and no hemorrhage, hematoma, pseudoaneurysm, arteriovenous fistula, or other complications developed. During a mean follow-up of 9.8 months ± 1.5, claudication severity, rest pain, and toe ulcers improved significantly. The pulse of the distal arteries, as well as the filling of the veins, could be distinctly felt. Ankle-brachial index changed from 0.48 ± 0.17 to 0.84 ± 0.11 at 1 year after intervention (P < .001), and patency rates at 1, 6, and 12 months after interventions were 100%, 80%, and 42%, respectively.ConclusionsA dual femoral–popliteal approach in the supine position is an alternative backup option after failed attempts at the antegrade approach for patients with proximal barriers in CTO or lesions with major extending collateral vessels.     

Metallic stents in benign biliary strictures: long-term effectiveness and interventional management of stent occlusion

OBJECTIVE: The objective of our study was to evaluate the long-term effectiveness of metallic stent placement in the treatment of benign biliary strictures and to report our experience with interventional procedures for the management of stent occlusion to achieve secondary patency. CONCLUSION: The clinical course of these patients is compromised by repeated stent occlusions, caused by stone or mucosal hyperplasia. The results of primary stent patency are disappointing with the primary patency rate decreasing from 75% after 12 months to 25% after 36 months. The different interventional procedures used to restore bile flow make an important contribution to the secondary stent patency and provide a satisfactory clinical result in a patient subpopulation in whom stent placement is considered the last resort.     

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.     

Angioplasty of the pelvic and femoral arteries in PAOD: Results and review of the literature

Purpose

Evaluation of percutaneous recanalization of obstructed iliac as well as superficial femoral arteries (SFAs) in patients with peripheral arterial obstructive disease (PAOD).

Material and methods

The data of 195 consecutive patients with 285 obstructions of the common and or external iliac artery as well as the data of 452 consecutive patients with 602 long occlusions (length > 5 cm) of the SFA were retrospectively analyzed. The lesions were either treated with percutaneous transluminal angioplasty (PTA) or Excimer laser assisted percutaneous transluminal angioplasty (LPTA). Overall 316 stents were implanted (Nitinol stents: 136; stainless steel stents: 180) in the iliac artery and 669 stents were implanted (Nitinol stents: 311; Easy Wallstents: 358) in the SFA. The follow-up period was 36-65 months (mean 46.98 ± 7.11 months) postinterventionally using clinical examination, ABI calculation, and color-coded duplex sonography. Patency rates were calculated on the basis of the Kaplan-Meier analysis.

Results

The overall primary technical success rate was 97.89% for the iliac arteries and 92.35% for the SFA. Minor complications (hematoma, distal emboli and vessel dissection) were documented in 11.79% for the iliac arteries and 7.97% for the SFA. The primary patency rate was 90.3% for the iliac and 52.8% for the SFA after 4 years. The secondary patency rate was 96.84% for the iliac and 77.8% for the SFA after 4 years.

Conclusion

Percutaneous recanalization of iliac and superficial femoral artery obstructions is a safe and effective technique for the treatment of patients with PAOD. By consequent clinical monitoring high secondary patency rates can be achieved. The use of a stents seems to result in higher patency rate especially in the SFA when compared to the literature in long-term follow-up.     

Predictors of long-term results after treatment of iliac artery obliteration by transluminal angioplasty and stent deployment

Purpose: To investigate initial and long-term success rate after percutaneous treatment of iliac artery occlusion with angioplasty and stent deployment. To investigate the influence of vascular comorbidity, lesion length, stent placement and lesion coverage as possible predictors of outcome. Methods: Between January 1994 and December 1999, 80 iliac recanalizations were performed on 78 patients, median age 61.1 ± 11.5 (SD) years. All patients were followed up by clinical examinations, duplex ultrasound and intravenous digital subtraction angiography. Mean follow-up time was 2.0 ± 1.53 (SD) years. Multivariate Cox regression analysis was used to determine the influence of cofactors on patency. Results: One, 2 and 4 years after recanalization, primary patency was 78.1%, 74.5% and 64.0%; secondary patency was 88.8%, 88.8% and 77.9%, respectively. Patients with shorter occlusions, complete lesion coverage and patent ipsilateral femoral arteries had significantly longer patency rates. Complications included inguinal hematoma (n=1), technical failure (n=3) aortic dissection (n=1), embolic occlusions (n=7), gluteal claudication (n=1) and genital necrosis after subsequent urethral surgery in one patient with contralateral occlusion and ipsilateral overstenting of the internal iliac artery with subsequent stenosis. Complications were of permanent clinical significance in seven of 78 (9%) of the patients. In 17 (22%) cases, percutaneous reintervention was performed with angioplasty in the stent (n=16) or deployment of a new stent (n=1). Conclusion: Endoluminal stent placement has its place in an interdisciplinary therapeutic approach as a viable therapeutic alternative to major transabdominal bypass surgery and can be performed with comparable complication rates. Patients with short occlusions, patent femoral arteries, and stents covering the entire occlusion have significant longer patency.     

Metallic stents deployed in synthetic arteriovenous hemodialysis grafts

OBJECTIVE: The purpose of our study was to review the success of metallic stent treatment of intragraft stenoses in patients with synthetic arteriovenous hemodialysis grafts. MATERIALS AND METHODS: Between May 1993 and May 1997, 19 metallic stents were placed in 11 patients (seven women, four men; age range, 41-83 years) to treat elastic intragraft stenoses or graft dissections. Before stent placement, all patients had experienced multiple episodes of graft thrombosis, had very limited vascular access for hemodialysis, and were considered poor surgical candidates. RESULTS: The technical success rate was 100%, and there were no procedural complications. Using life-table analysis, we found primary patency to be 36% at 6 months after stent placement, 12% at 12 months, and 12% at 18 months. Secondary patency was 91% at 6 months after stent placement, 71% at 12 months, and 47% at 18 months. The mean and median patencies per intervention were 4.2 and 3.6 months, respectively. Mean and median secondary graft patencies were both 14 months (range, 3 days-32 months). Puncture through the stents occurred during dialysis, causing stent distortion and fracture. Eight stents had a linear fracture suggesting compression contributed to the stent distortion. No clinically evident complications related to stent placement occurred. CONCLUSION: Metallic stent deployment can salvage access in synthetic arteriovenous grafts by alleviating intragraft stenoses. Patency of intragraft stents is similar to venous stents used to treat other hemodialysis-related stenoses; however, fracture of Wall-stents occurs with prolonged graft use, especially in areas of needle punctures.     

Technique, Complication, and Long-Term Outcome for Endovascular Treatment of Iliac Artery Occlusion

The aim of this study was to report technical details, procedure-related complications, and results of endovascular treatment in chronic iliac artery occlusion. Between 2001 and 2008, endovascular treatments of 127 chronic iliac artery occlusions in 118 patients (8 women and 110 men; mean age, 59 years) were retrospectively reviewed. The study was based on Ad Hoc Committee on Reporting Standards (Society for Vascular Surgery/International Society for Cardiovascular Surgery Standards). All occlusions were treated with stent placement with or without preliminary balloon angioplasty. Kaplan–Meier estimators were used to determine patency rates. Univariate and multivariate analyses were performed to determine variables affecting successful recanalization, major complications, early stent thrombosis (≤30 days), and primary and secondary patency rates. Initial technical success was achieved in 117 (92%) procedures. Successful recanalization was obtained by antegrade approach in 69 of 77 (90%) procedures and by retrograde approach in 52 of 105 (50%) procedures (p < 0.001). Complications were encountered in 28 (24%) patients [minor in 7 patients (6%) and major in 22 patients (19%)]. One death occurred in the operative period secondary to iliac artery rupture. Early stent thrombosis was seen in eight (7%) patients. Presence of critical limb ischemia (p = 0.03), subintimal recanalization (p = 0.03), and major complication (p = 0.02) were the independent predictors of early stent thrombosis on multivariate analysis. Primary and secondary patency rates at 5 years were 63 and 93%, respectively. Presence of critical limb ischemia, TASC type C iliac lesions, combined occlusions of both common and external iliac arteries, and major complications were associated with decreased patency rates on univariate analysis, whereas these factors were not independent predictors of stent patency on multivariate analysis. In conclusion, endovascular treatment of iliac artery occlusion has a high technical success rate with favorable long-term patency rate. Success of recanalization increases with use of the antegrade approach and with the presence of a stump of artery before the occlusion.     

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.