Long-term outcomes of primary angioplasty and primary stenting of central venous stenosis in hemodialysis patients

Hemodialysis Tunneled Catheter Noninfectious Complications

Noninfectious hemodialysis catheter complications include catheter dysfunction, catheter-related thrombus, and central vein stenosis. The definitions, causes, and treatment strategies for catheter dysfunction are reviewed below. Catheter-related thrombus is a less common but serious complication of catheters, requiring catheter removal and systemic anticoagulation. In addition, the risk factors, clinical manifestation, and treatment options for central vein stenosis are outlined.

Comparison of Open-Cell Stent and Closed-Cell Stent for Treatment of Central Vein Stenosis or Occlusion in Hemodialysis Patients

Background

Central vein stenosis or occlusion is a common complication that can lead to significant morbidity and dysfunction of access in the hemodialysis patient. More lesions can develop over time, and preserving access becomes a challenge as life expectancy of the hemodialysis patient increases.

Objectives

The goal was to compare long-term results and determine the outcomes of open-cell stent versus closed-cell stent for central vein stenosis or occlusion in hemodialysis patients.

Patients and Methods

From 1997 to 2015, in 401 hemodialysis patients, stent placement for central vein stenosis or occlusion was performed if balloon angioplasty was unsatisfactory, due to elastic recoil or occurrence of restenosis within 3 months. When thrombus was present, primary stenting was performed. A total of 257 open-cell stents and 144 closed-cell stents were used. Angiographic findings including lesion site, central vein stenosis or occlusion, and presence of thrombosis and complication were evaluated. Primary patency rate and mean patency rate of the stent were compared between two stent groups by Kaplan-Meier survival analysis.

Results

For the open-cell stent group, 159 patients were diagnosed as central vein stenosis and 98 were occlusion. For the closed-cell stent group, 78 were stenosis and 66 were occlusion. There were two complications for central migration and two for procedure-related vein rupture. Open-cell stents and closed-cell stents had mean patency rates of 10.9 ± 0.80 months and 8.5 ± 10.87 months, respectively (P = 0.002).

Conclusion

The open-cell stent is effective and its performance is higher than that obtained with the closed-cell stent for treating central vein stenosis or occlusion in hemodialysis patients.

Effect of regional versus local anaesthesia on outcome after arteriovenous fistula creation: a randomised controlled trial

BACKGROUND

Arteriovenous fistulae are the optimum form of vascular access in end-stage renal failure. However, they have a high early failure rate. Regional compared with local anaesthesia results in greater vasodilatation and increases short-term blood flow. This study investigated whether regional compared with local anaesthesia improved medium-term arteriovenous fistula patency.

METHODS

This observer-blinded, randomised controlled trial was done at three university hospitals in Glasgow, UK. Adults undergoing primary radiocephalic or brachiocephalic arteriovenous fistula creation were randomly assigned (1:1; in blocks of eight) using a computer-generated allocation system to receive either local anaesthesia (0·5% L-bupivacaine and 1% lidocaine injected subcutaneously) or regional (brachial plexus block [BPB]) anaesthesia (0·5% L-bupivacaine and 1·5% lidocaine with epinephrine). Patients were excluded if they were coagulopathic, had no suitable vessels, or had a previous failed ipsilateral fistula. The primary endpoint was arteriovenous fistula patency at 3 months. We analysed the data on an intention-to-treat basis. This study was registered with ClinicalTrials.gov (NCT01706354) and is complete.

FINDINGS

Between Feb 6, 2013, and Dec 4, 2015, 163 patients were assessed for eligibility and 126 patients were randomly assigned to local anaesthesia (n=63) or BPB (n=63). All patients completed follow-up on an intention-to-treat basis. Primary patency at 3 months was higher in the BPB group than the local anaesthesia group (53 [84%] of 63 patients vs 39 [62%] of 63; odds ratio [OR] 3·3 [95% CI 1·4-7·6], p=0·005) and was greater in radiocephalic fistulae (20 [77%] of 26 patients vs 12 [48%] of 25; OR 3·6 [1·4-3·6], p=0·03). There were no significant adverse events related to the procedure.

INTERPRETATION

Compared with local anaesthesia, BPB significantly improved 3 month primary patency rates for arteriovenous fistulae.

FUNDING

Regional Anaesthesia UK, Darlinda's Charity for Renal Research.

Management of venous hypertension following arteriovenous fistula creation for hemodialysis access

INTRODUCTION

Venous hypertension (VH) is a distressing complication following the creation of arteriovenous fistula (AVF). The aim of management is to relieve edema with preservation of AVF. Extensive edema increases surgical morbidity with the loss of hemodialysis access. We present our experience in management of VH.

METHODS

A retrospective study was conducted on 37 patients with VH managed between July 2005 to May 2014. Patient demographics, evaluation, and procedures performed were noted. A successful outcome of management with surgical ligation (SL), angioembolization (AE), balloon dilatation (BD) or endovascular stent (EVS) was defined by immediate disappearance of thrill and murmur with resolution of edema in the next 48-72 h, no demonstrable flow during check angiogram and resolution of edema with preservation of AVF respectively.

RESULTS

All 8 distal AVF had peripheral venous stenosis and were managed with SL in 7 and BD in one patient. In 29 proximal AVF, central and peripheral venous stenosis was present in 16 and 13 patients respectively. SL, AE, BD, and BD with EVS were done in 18, 5, 4, and 3 patients, respectively. All patients had a successful outcome. SL was associated with wound related complications in 11 (29.73 %) patients. A total of 7 AVF were salvaged. One had restenosis after BD and was managed with AE. BD, EVS, and AE had no associated morbidity.

CONCLUSIONS

Management of central and peripheral venous stenosis with VH should be individualized and in selected cases it seems preferable to secure a new access in another limb and close the native AVF in edematous limb for better overall outcome.

Stent Grafts Provided Superior Primary Patency for Central Venous Stenosis Treatment in Comparison with Angioplasty and Bare Metal Stent: A Retrospective Single Center Study on 70 Hemodialysis Patients

PURPOSE

To compare patency in dialysis patients following different endovascular treatment of symptomatic central venous stenosis.

MATERIALS AND METHODS

A 10-year retrospective evaluation in 70 patients (32 men) dialyzing through vascular access (33, 47%) and tunneled catheters (37, 53%) was made. Three cohorts were compared: angioplasty alone (22), bare metal stent (28), and stent graft (20). Patencies were described with Kaplan-Meier method, and Cox uni- and multivariate models were analyzed to find factors associated.

RESULTS

All patients had a favorable anatomical and clinical outcome. Restenosis occurred in 22 (31%) of 70 patients requiring 41 additional interventions; 34 of 70 patients died (median follow-up 19.4 months). Primary patency at 3, 6, 12, and 24 months was 100%, 100%, 100%, and 84% for stent graft versus 90%, 79%, 58%, and 43% for angioplasty (P = .014) versus 84%, 80%, 75%, and 46% for bare-metal stent (P = .062). The overall comparison was more favorable for stent graft (P = .020) when the sites of lesions were matched. Patencies for angioplasty and bare-metal stents were equivalent (P = .141). A lower risk of restenosis (hazard rate [HR] 0.20, confidence interval [CI] 0.06-0.7) and fewer reinterventions (P < .01) were associated with stent graft, whereas age (HR 1.04, CI 1.001-1.08) and cardiovascular disease (HR 2.26, CI 1.06-4.84) influenced the overall survival. No difference in assisted primary patency was found.

CONCLUSION

Stent graft seems to improve primary patency for central venous stenosis and requires fewer reinterventions in a dialysis population with a high prevalence of long-term catheters.

Pacemaker implantation in superior vena cava obstruction: Re-canalization, venoplasty, and stenting

Techniques to overcome challenging venous anatomy have become an increasingly important part of modern day cardiac device implantation. Complete superior vena cava (SVC) obstruction, however, is a rare and serious clinical entity, and consequently there is limited clinical experience in addressing this pathology in the context of transvenous pacemaker implantation. We present the case of a 48-year-old renal transplant patient with sick sinus syndrome and recurrent syncope, who had an upper SVC occlusion and a failed epicardial pacing system. The SVC was re-canalized and stented using techniques derived from chronic total occlusion coronary angioplasty, thus allowing successful implantation of a transvenous pacemaker lead. This case highlights the increased risk of developing central venous occlusion that exists in renal dialysis patients, and demonstrates the benefits of utilizing transferable interventional coronary and radiology techniques to overcome this pathology and facilitate pacemaker implantation. <Learning objective: Renal dialysis patients with implantable cardiac devices are at an increased risk of developing complications that include central venous obstruction. Advanced angioplasty techniques can be used to overcome complete venous obstruction and facilitate endovascular lead implantation.>.

Stent and Stent-Graft Use in Arteriovenous Dialysis Access

Dialysis access failure is a major cause of mortality and morbidity among dialysis patients. Preservation of access is critical to maintaining hemostasis, avoiding uremia, and managing the complications of kidney failure. While angioplasty remains the most common method of managing arteriovenous (AV) access stenoses, the use of stents and stent grafts to manage venous stenoses associated with AV access has become more prominent. There have been several prospective randomized trials that have demonstrated the benefit of these devices in maintaining the target lesion patency of the treated areas. In this article, the author reviews the data relating to stent and stent-graft use at the venous anastomosis and outflow veins for pseudoaneurysms of grafts, at the cephalic arch, and for central venous stenoses.

The value of intravascular ultrasound in the treatment of central venous obstructions in hemodialysis patients

INTRODUCTION

Digital subtraction angiography (DSA) is the gold standard in diagnosis and treatment of central venous obstructions (CVOs) in hemodialysis access. However, growing data suggest that DSA might underestimate the degree and morphology of venous outflow stenosis. This could lead to inappropriate CVO management. Intravascular ultrasound (IVUS) has been shown to identify lesion characteristics remaining obscure with angiography. With the current study we suggest IVUS as an eminent imaging modality in CVO management.

METHODS

Twelve patients (8 male, mean age 62.4 ± 9 years) were analyzed for suspicion of symptomatic CVO. Both angiography and IVUS evaluation were performed to determine the degree of obstruction before and after PTA. Stent placement was indicated when significant residual stenosis (&gt;50% lumen reduction) was suspected.

RESULTS

Conventional plain angiography determined 8 out of 12 central venous lesions significant. Secondary signs of obstruction, i.e., collateral filling, was present in all 12 cases. After PTA, persistent significant stenosis was observed in 3 out of 12 patients. IVUS showed significant lumen reduction in all 12 cases. Additionally, IVUS showed a median cross-sectional area of 24 ± 12 mm2 before PTA and 37 ± 23 mm2 after PTA (NS). Furthermore, IVUS showed signs of intraluminal fibrotic trabeculations in 9 patients. Stenting was performed in 10 patients with &gt;50% lumen reduction on IVUS after PTA.

CONCLUSIONS

Conventional angiography seems unreliable to identify all significant aspects of a central venous outflow obstruction. Additional use of IVUS might aid in the decision-making process and select the optimal treatment strategy.

The Use of HeRo Catheter in Catheter-dependent Dialysis Patients with Superior Vena Cava Occlusion

Objectives

Hemodialysis (HD) patients with superior vena cava (SVC) occlusion have limited access options. Femoral access is commonly employed but is associated with high complication rates. Hemodialysis Reliable Outflow (HeRO) catheters can be used in tunneled catheter-dependent (TCD) patients who have exhausted other access options. The HeRO graft bypasses occlusion and traverses stenosis with outflow directly into the central venous circulation. At our institution we have used the inside-out central venous access technique (IOCVA) to traverse an occluded vena cava for HeRO graft placement. We review our experience with this technique.

Methods

A retrospective chart review was conducted of patients with HeRO graft placement at our institution. All were dependent on a tunneled femoral dialysis catheter due to central venous occlusion (CVO). The IOCVA technique was used in each case. This technique was used as last resort for patients who had no other dialysis access option. Demographics, patency rates, complications, and mortality were recorded.

Results

A total of 11 HeRO grafts were placed in 11 patients from January 2012 to June 2013, with 100% technical success rate. Three grafts were ligated due to steal syndrome. Two grafts were lost due to thrombosis. Five of 11 patients experienced a 30-day complication. Three patients died within the follow-up period; however, none were directly related to the graft placement. Follow up range was 65-573 days; 5 of 11 grafts were used for dialysis at the end of the follow-up period. The 12-month patency rate was 30%.

Conclusions

HeRO grafts are one option for dialysis patients with CVO. There is, however, a high incidence of steal syndrome and other complications. These grafts should be offered as a final potential alternative to catheter dependence.

Endovascular treatment of central venous obstruction as a complication of prolonged hemodialysis - Preliminary experience in a tertiary care center

Background:

Central venous disease is a serious complication in patients undergoing hemodialysis, often presenting with symptoms of venous hypertension. Treatment is aimed to provide symptomatic relief and to maintain hemodialysis access site patency.

Aim:

To describe our initial experience in the endovascular treatment of central venous stenosis or obstruction in patients undergoing hemodialysis.

Settings and Design:

This was a retrospective study carried out in a tertiary care center. Study duration was 24 months. Follow-up was variable.

Materials and Methods:

Eleven patients of chronic renal failure undergoing hemodialysis presented with central vein stenosis or obstruction having ipsilateral vascular access, between July 2012 and July 2014. All the patients underwent endovascular treatment and were analyzed retrospectively.

Results and Conclusion:

A total of 11 patients (4 male and 7 female) underwent 18 interventions for 13 stenotic segments during a time period of 2 years. Eight stenotic segments were in brachiocephalic vein, three in subclavian vein, and two in axillary veins. The technical success rate for endovascular treatment was 81.8%. Two patients underwent percutaneous transluminal angioplasty (PTA) alone and presented with restenosis later. Balloon angioplasty followed by stenting was done in seven patients, two of which required reintervention during follow-up. We found endovascular treatment safe and effective in treating central venous disease.

Endovascular interventions for central vein stenosis

Central vein stenosis is common because of the placement of venous access and cardiac intravascular devices and compromises vascular access for dialysis. Endovascular intervention with angioplasty and/or stent placement is the preferred approach, but the results are suboptimal and limited. Primary patency after angioplasty alone is poor, but secondary patency can be maintained with repeated angioplasty. Stent placement is recommended for quick recurrence or elastic recoil of stenosis. Primary patency of stents is also poor, though covered stents have recently shown better patency than bare metal stents. Secondary patency requires repeated intervention. Recanalization of occluded central veins is tedious and not always successful. Placement of hybrid graft-catheter with a combined endovascular surgical approach can maintain patency in many cases. In the presence of debilitating symptoms, palliative approach with endovascular banding or occlusion of the access may be necessary. Prevention of central vein stenosis is the most desirable strategy.

The Role of Endovascular Stents in Dialysis Access Maintenance

Vascular stenosis is most often the culprit behind hemodialysis vascular access dysfunction, and although percutaneous transluminal angioplasty remains the gold standard treatment for vascular stenosis, over the past decade the use of stents as a treatment option has been on the rise. Aside from the 2 Food and Drug Administration-approved stent grafts for the treatment of venous graft anastomosis stenosis, use of all other stents in vascular access dysfunction is off-label. Kidney Disease Outcomes Quality Initiative recommends limiting stent use to specific conditions, such as elastic lesions and recurrent stenosis; otherwise, additional adapted indications are in procedure-related complications, such as grade 2 and 3 hematomas. Published reports have shown the potential use of stents in a variety of conditions leading to vascular access dysfunction, such as venous graft anastomosis stenosis, cephalic arch stenosis, central venous stenosis, dialysis access aneurysmal elimination, cardiac implantable electronic device-induced stenosis, and thrombosed arteriovenous grafts. Although further research is needed for many of these conditions, evidence for recommendations has been clear in some; for instance, we know now that stents should be avoided along cannulation sites and should not be used in eliminating dialysis access aneurysms. In this review article, we evaluate the available evidence for the use of stents in each of the aforementioned conditions leading to hemodialysis vascular access dysfunctions.

Brachiocephalic Vein Stenting and Body-Floss Technique as a Treatment of CVD in Dialysis-Dependent Patient - Case Report and Literature Review

Background

Given the increasing number of elderly hemodialysis-dependent patients with concomitant chronic diseases the successful creation and maintenance of reliable vascular access become a real challenge. In current literature central vein disease (CVD) is defined as at least 50% narrowing up to total occlusion of central veins of the thorax including superior vena cava (SVC), brachiocephalic (BCV), subclavian (SCV) and internal jugular vein (IJV). The incidence of CVD has been reported to be as high as 23% in the total dialysis population and 41% in those with access related complains.

Case Report

61-year-old man has been admitted to the local radiology department with symptoms of the superior vena cava syndrome. The venography revealed occlusion of the right brachiocephalic vein. Due to Tortuosity and lack of stamp of right subclavian vein contributed to the decision to perform recanalization by “body floss” technique. In a further step we have performed PTA of obstructed vein segment using 7×40 mm balloon. Due to the presence of residual stenosis it was decided to implant two self – expanding stents 10×40 mm. After the procedure the patient was discharged in good condition and transferred to dialysis center.

Conclusions

Main objective was the salvage of a functioning arteriovenous fistula. Performed endovascular intervention is a safe and effective approach to correct CVD for a short term. To ensure long lasting effects the patient will require enhanced follow-up and inevitable reinterventions. For that matter, prevention of CVD remains critical.

Retrospective study in 23 patients of the self-expanding sinus-XL stent for treatment of malignant superior vena cava obstruction caused by non-small cell lung cancer

PURPOSE

To evaluate retrospectively the self-expanding nitinol Sinus-XL stent (OptiMed, Ettlingen, Germany) for the treatment of superior vena cava (SVC) obstruction caused by non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

Between October 2009 and December 2012, 23 patients (7 women and 16 men; age, 62.5 y ± 8.5) with stage IIIA (1 patient), IIIB (4 patients) or IV (18 patients) NSCLC and acute SVC obstruction were scheduled for urgent stent implantation. The primary study endpoints were technical success (defined as accurate stent placement with complete coverage of the obstructed SVC), residual stenosis < 30%, and clinical efficacy. Complications were assessed as a secondary study endpoint.

RESULTS

There were 26 stents implanted in 23 patients. The technical success was 100%. Stent dilation was performed after deployment in 18 cases (78%). Stent migration into the right atrium occurred immediately after deployment in one patient; however, this stent was successfully repositioned and stabilized by a second stent. The clinical symptoms improved at least one category according to the International Consensus Committee on Chronic Venous Disease after stent implantation in all but one patient. The mean clinical follow-up was 66 days ± 83 (range, 1-305 d). Three minor complications (13%) and one major complication (4%) occurred.

CONCLUSIONS

Implantation of the self-expanding Sinus-XL stent for treatment of SVC obstruction caused by NSCLC is a safe and effective urgent treatment in this palliative setting.

Thrombotic complications in children from short-term percutaneous central venous catheters: what can we do?

The reported incidence of venous thromboembolism (VTE) in children has increased dramatically over the past decade, and the primary risk factor for VTE in neonates and infants is the presence of a central venous catheter (CVC). Although the associated morbidity and mortality are significant, very few trials have been conducted in children to guide clinicians in the prophylaxis, diagnosis, and treatment of CVC-related VTE. Furthermore, pediatric guidelines for prophylaxis and management of VTE are largely extrapolated from adult data. How then should the anesthesiologist approach central access in children of different ages to lessen the risk of CVC-related VTE or in children with prior thrombosis and vessel occlusion? A comprehensive review of the pediatric and adult literature is presented with the goal of assisting anesthesiologists with point-of-care decision-making regarding the risk factors, diagnosis, and treatment of CVC-related VTE. Illustrative cases are also provided to highlight decision-making in varying situations. The only risk factor strongly associated with CVC-related VTE formation in children is the duration of the indwelling CVC. Several other factors show a trend toward altering the incidence of CVC-related VTE formation and may be under the control of the anesthesiologist placing and managing the catheter. In particular, because children with VTE may live decades with its sequelae and chronic vein thrombosis, careful consideration of lessening the risk of VTE is warranted in every child. Further studies are needed to form a clearer understanding of the risk factors, prophylaxis, and management of CVC-related VTE in children and to guide the anesthesiologist in lessening the risk of VTE.

Evaluating and treating venous outflow stenoses is necessary for the successful open surgical treatment of arteriovenous fistula aneurysms

BACKGROUND

Arteriovenous fistula (AVF) aneurysms (AVFAs) can lead to skin erosion, bleeding, difficult access while on hemodialysis, and poor cosmetic appearance. We reviewed our experience in treating patients with aneurysmal dilatation of their AVF.

METHODS

We reviewed clinical data of 48 patients (37 men; overall mean age, 55 years; range, 28-85 years) with an AVFA who underwent treatment during a 30-month period. Relevant clinical variables and treatment outcomes were analyzed.

RESULTS

All patients underwent a fistulogram, and 90% required percutaneous angioplasty to improve outflow. Fifty-six percent of patients had one stenotic outflow lesion, and 44% had at least two tandem outflow stenoses that required treatment. Open repair with aneurysmorrhaphy was performed in one stage in 64% of patients and in two stages in 36%. A tunneled hemodialysis catheter was required in 11 patients (23%) until the surgically repaired AVF was ready for use again, comprising 10 patients treated with single-stage surgery and only one patient in the staged group. All AVFAs were effectively treated, and patients were able to maintain functional use of their access when healed.

CONCLUSIONS

There is a high association of venous outflow stenoses and AVFA. Comprehensive therapy should encompass treatment of any venous outflow stenoses before open AVFA repair. A two-stage repair may decrease tunneled hemodialysis catheter use in patients with multiple aneurysms.

Percutaneous Transluminal Angioplasty for Central Venous Disease in Dialysis Patients: Influence on Cardiac Function

Purpose

Increased vascular access flow after percutaneous transluminal angioplasty (PTA) for central venous stenosis and occlusion (central venous disease, CVD) can affect cardiac function in hemodialysis (HD) patients. We evaluated the cardiac function, etiology, and treatment in HD patients with CVD.

Methods

HD patients with CVD treated by PTA between June 2006 and February 2013 were studied.

Results

Of the 26 patients, 22 had left arteriovenous fistulas (AVFs), 1 left arteriovenous graft (AVG), 2 right AVFs, and 1 right AVG. CVD sites were the left brachiocephalic vein (LBCV; n=13), left subclavian vein (LSCV; n=7), both LBCV and LSCV (n=3), right BCV (n=2), and right SCV (n=1). Computed tomography findings indicated a high extrinsic compression rate for the LBCV (91%) and LSCV (50%). The success rate of PTA was 96%. The primary patency rates at 3, 6, 9, and 12 months were 81%, 73%, 65%, and 57%, respectively. The post-PTA brachial artery flow volume was significantly increased compared with the pre-PTA volume (1306 vs. 957 ml/min; p=0.005). The post-PTA left ventricular ejection fraction and expiration inferior vena cava diameter were the same as the pre-PTA values (57% versus 60%, p=0.2 and 17 versus 17 mm, p=0.9, respectively).

Conclusions

Our findings suggest that increased vascular access flow after PTA for CVD has no relation to cardiac function.

Wandering stent within the pulmonary circulation

To present a case of a wandering stent within the pulmonary circulation that was managed conservatively with the "wait-and-see" strategy. Accidental dislodgement of a left brachiocephalic vein stent into the left lower lobe pulmonary artery occurred in an 83-year-old patient suffering from end-stage renal disease during placement of a left jugular vein catheter. The following day, a second X-ray revealed migration of the stent from the left to the right lower lobe pulmonary artery. Our patient was managed conservatively with low-molecular-weight heparin and was discharged on clopidogrel. The patient remained asymptomatic with regard to the migrated stent for four and a half years and died of old age. This is the first case of a wandering stent within the pulmonary circulation reported in the literature, supporting the "wait-and-see" policy in the management of such patients.

Treatment of hemodialysis vascular access arteriovenous graft failure by percutaneous intervention

A patent vascular access is the lifeline of end-stage renal disease patients depending on hemodialysis treatment. Once a functioning vascular access has been established, maintaining its patency is of utmost importance. During the last decades percutaneous techniques became increasingly important for the treatment of hemodialysis vascular access graft failure. In this review, the role of percutaneous balloon angioplasty and stent implantation is evaluated for different clinical scenarios, based on the available evidence.

Extending the longevity of a complicated arteriovenous fistula using endovascular intervention

A brachiocephalic arteriovenous fistula was complicated by a central venous stenosis, which could not be relieved. A cephalojugular bypass was performed using an interpositoned graft, which later developed tight stenoses at both ends of the graft. This was successfully treated with endovascular intervention, extending the longevity of the vascular access.

Long Segment Recanalization and Dedicated Central venous Stenting in an Ultimate Attempt to Restore Vascular access Central Vein Outflow

Purpose

Maintaining vascular access in patients undergoing chronic hemodialysis is a challenging process, especially in patients enduring multiple central line placements and in whom peripheral options have been exhausted.

Case

We present a case of a 60-year-old male without options for peripheral vascular access due to multiple failed arteriovenous fistulas for hemodialysis. Furthermore, bilateral subclavian, brachiocephalic veins and iliac veins were occluded or significantly obstructed. After long segment central vein recanalization, an upper arm loop arteriovenous graft was implanted. The recanalized segment was stented with a 12-mm dedicated venous nitinol stent.

Conclusion

Chronic central vein obstructions demand stents with both high radial force and flexibility. We recommend dedicated venous stents to improve technical success and reduce stent-related complications like early re-occlusion due to fracturing, kinking or straightening.

Natural history of venous morphologic changes in dialysis access stenosis

PURPOSE

Venous stenosis secondary to neointimal hyperplasia is a major etiology of early arteriovenous fistula (AVF) failure. The natural history of AVF failure is likely influenced by progressive vascular insults to the vein prior to and after AVF creation. The main objectives of this study were to (1) provide a histologic and morphometric description of non-chronic kidney disease (CKD), upper extremity vein specimens and (2) perform a morphometric analysis to study venous histology from non-CKD upper extremity veins, veins collected at the time of new vascular access surgery and veins collected from failed stenotic AVFs.

METHODS

Vein samples from 11 non-CKD deceased donors, 29 subjects receiving new vascular access creation and 20 subjects with stenotic failed AVFs were collected for histologic and morphometric analysis.

RESULTS

The mean values of average intima/media thickness ± S.E. from veins collected from non-CKD subjects, subjects receiving new vascular access and subjects with stenotic AVFs were 0.16±0.02, 0.43±0.07 and 3.84±0.55, respectively (p<0.0001). Among donor, non-CKD, vein samples, only diabetes (p=0.0007) was associated with increased average intima/media thickness.

CONCLUSIONS

Our results demonstrate a progressively increasing venous neointimal hyperplasia development from the non-CKD period through the period of AVF creation and failure. Vascular injuries from complications of progressive CKD prior to access placement and vascular injuries after vascular access placement may play important roles in these progressive vascular changes, and need to be further elucidated.

Stent grafts for central venous occlusive disease in patients with ipsilateral hemodialysis access

PURPOSE

To assess long-term outcomes of stent grafts in patients with symptomatic central venous stenoses and occlusions ipsilateral to hemodialysis grafts or fistulas.

MATERIALS AND METHODS

The 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.

RESULTS

All 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.

CONCLUSIONS

Central 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.

Hemodialysis catheter malposition induced by a brachiocephalic vein stenosed stent

Malposition of a central venous hemodialysis catheter, mainly due to central vein stenosis or thrombosis, is not an uncommon complication. Herein, we present a rare cause of a left external jugular vein hemodialysis catheter, malpositioned into the ipsilateral internal jugular-subclavian venous route, due to a stenosed stent that has been placed into the ipsilateral brachiocephalic vein.

Central vein stenosis

Central vein stenosis (CVS) is commonly seen in patients receiving hemodialysis through an arteriovenous access, threatening the usability of arteriovenous access for dialysis. Subclavian and internal jugular catheters are prime reasons for the development of CVS, especially in the setting of long-term use of multiple catheters. CVS related to cardiac rhythm devices also is seen frequently. Idiopathic CVS can be encountered, although it is less common. Clinical features ultimately become sufficiently prominent to prompt angiographic evaluation. CVS should be evaluated carefully because management must be individualized. The primary method for treatment of CVS is endovascular intervention, including angioplasty and stent placement, whereas surgical options should be pursued in only refractory cases due to the invasiveness of the intervention. Early referral of patients for chronic kidney disease care; timely discussion of kidney replacement modality choices, including nonhemodialysis options such as peritoneal dialysis and kidney transplantation; placement of arteriovenous access prior to the onset of dialysis; and avoidance of catheters and other central vein instrumentation will prevent the development of CVS in most patients with kidney disease.

Reported outcomes after the endovascular treatment of chronic cerebrospinal venous insufficiency

Chronic cerebrospinal venous insufficiency (CCSVI) has recently been implicated as a potential causal factor in the development of multiple sclerosis (MS). The treatment of jugular and azygous vein stenoses, characteristic of CCSVI, has been proposed as a potential component of therapy for MS. In the few short years since Dr. Paulo Zamboni published "A Prospective Open label Study of Endovascular Treatment of Chronic Cerebrospinal Venous Insufficiency", there has been tremendous patient-driven demand for treatment. Concurrently, there have been numerous publications since 2009 addressing CCSVI and its association with MS. The purpose of this article is to present a brief review of CCSVI and its association with MS and to review the available literature to date with a focus on outcomes data.

Central venous disease in hemodialysis patients: an update

Central venous occlusive disease (CVD) is a common concern among the hemodialysis patient population, with the potential to cause significant morbidity. Endovascular management of CVD, comprising percutaneous balloon angioplasty and bare-metal stenting, has been established as a safe alternative to open surgical treatment. However, these available treatments have poor long-term patency, requiring close surveillance and multiple repeat interventions. Recently, covered stents have been proposed and their efficacy assessed for the treatment of recalcitrant central venous stenosis and obstruction. Moreover, newly proposed algorithms for the surgical management of CVD warrant consideration. Here, we seek to provide an updated review of the current literature on the various treatment modalities for CVD.

Central vein stenosis in an Asian hemodialysis population

Objective and background: Central vein stenosis occurs commonly after instrumentation of the major thoracic veins. We aimed to investigate factors that contributed to this condition in an Asian hemodialysis population, and the results of intervention.

Patients and methods: Hemodialysis patients diagnosed with central vein stenosis between January 2003 and December 2008, were identified from the records of the National University Hospital, Singapore. Eligible controls had a minimum of 2 years of hemodialysis via an arteriovenous fistula and/or central venous catheter, without clinical or radiological evidence of central vein stenosis.

Results: Central vein stenosis was diagnosed in 108 patients. The most common presenting features were arm swelling (32%) and failed hemodialysis catheter insertion (28%). The median frequency of permanent hemodialysis catheter insertion in those who subsequently developed venous stenosis (1.44 per patient per year) was 4 times that of controls (0.36 per patient per year; p < 0.001). Ischemic heart disease ( p = 0.03) and in certain patients, arteriovenous fistula surgery were associated with the development of central vein stenosis; whereas line sepsis, diabetes, and hypertension were not. Central vein angioplasty was attempted in 53 patients; the primary patency was 52% at 1 year.

Conclusion: Central vein stenosis is associated with a higher frequency of hemodialysis catheter insertion and access surgery. Efforts to decrease permanent hemodialysis catheter use should reduce the incidence of central vein stenosis.

Killing Two Birds with One Stone: Subclavian Vein Bypass Graft for Relief of Venous Obstruction and Haemodialysis Access

Subclavian and brachio-cephalic vein stenosis or occlusion occurs, most commonly, as an iatrogenic complication of the placement of central venous catheter. This occurrence can cause ipsilateral arm swelling in a newly-created arteriovenous fistula (AVF). Critical central vein stenoses are often successfully managed by endovascular approach; occasionally, complete occlusion with symptomatic severe arm swelling and pain that does not respond to angioplasty requires ligation of the dialysis access. We report successful surgical management of an end-stage-renal-failure (ESRF) patient with symptomatic subclavian vein occlusion refractory to angioplasty in an ipsilateral arm with an existing functional brachio-basilic transposition arteriovenous fistula by performing a basilic to internal jugular vein (IJV) bypass graft, relieving both the arm swelling and salvaging the existing vascular access for future haemodialysis.

Subclavian vein angioplasty during arteriovenous fistula surgery: case report and literature review

Patients with chronic kidney disease stage 5 are generally treated by hemodialysis, preferentially performed via an arteriovenous fistula (AVF). We report the case of a 58-year-old male patient with diabetes mellitus, hypertension and end-stage renal disease in whom hemodialysis was conducted via a long-term catheter. His medical record described numerous central venous cannulations and several AVF creations. The patient developed subclinical subclavian stenosis that required creation of a new vascular access route. The purpose of this case report is to describe treatment of subclavian vein stenosis during AVF creation.

Ipsilateral jugular to distal subclavian vein transposition to relieve central venous hypertension in rescue vascular access surgery: a surgical report of 3 cases

Central venous thrombosis may often arise following central venous cannulation for temporary haemodialysis access. Venous thrombosis may be clinically asymptomatic due to the presence of collateral circulation. However, if an arteriovenous (AV) fistula is prepared below the obstructed venous segment, then symptoms may occur. Central venous hypertension interferes with dialysis, compromises limb function and threatens its safety. Percutaneous treatment is mostly used. However, in some cases endovascular treatment may not be as easy and long term patency uncertain.We report our experience on 3 patients on chronic hemodialysis treatment presenting with a patent AV fistula and ipsilateral subclavian vein chronic fibrotic obstruction. They were treated by ipsilateral internal jugular to distal subclavian vein transposition. Two separate surgical incisions were performed to expose the subclavian vein distally to the occlusion and the jugular vein that was distally ligated and transposed. There was no mortality nor significant postoperative complications. Resolution of hypertensive symptoms was achieved within 3-4 weeks in all patients. The AV fistula was used for dialysis treatment starting from the first postoperative day. At follow-up (mean 13 months), there was no recurrence of upper limb venous hypertension.In patients with subclavian occlusion and ipsilateral low flow, patent AV fistula, jugular to distal subclavian vein transposition may prove useful in cases when percutaneous angioplasty is technically not feasible or long term patency is not expected.

Surveillance and medical therapy following endovascular treatment of chronic cerebrospinal venous insufficiency

The debate regarding the possible link between chronic cerebrospinal venous insufficiency and multiple sclerosis (MS) is continuously becoming more and more contentious due to the current lack of level 1 evidence from randomized trials. Regardless of this continued uncertainty surrounding the safety and efficacy of this therapy, MS patients from Canada, and other jurisdictions, are traveling abroad to receive central venous angioplasty and, unfortunately, some also receive venous stents. They often return home with few instructions regarding follow-up or medical therapy. In response we propose some interim, practical recommendations for post-procedural surveillance and medical therapy, until further information is available.

Right intra-atrial catheter placement for hemodialysis in patients with multiple venous failure

The purpose of this study is to evaluate the efficacy and safety of direct right atrial catheter insertion for hemodialysis in patients with multiple venous access failure. We retrospectively evaluated the charts of 27 patients with multiple venous access failure who had intra-atrial dialysis catheter placement between October 2005 and October 2010 in our clinic. Permanent right atrial dialysis catheters were placed through a right anterior mini-thoracotomy under intratracheal general anesthesia in all patients. Demographics of the cases, the patency rates of hemodialysis via atrial catheterization, existence of any catheter thrombosis, and catheter-related infections were documented and used in statistical analysis. Seventeen women (63%) and 10 men (37%) with the mean age of 59.0 ± 7.1 years (47-71) were enrolled in this study. Chronic renal failure was diagnosed for the mean of 78.9 ± 24.3 months (33-130). Five patients (18.5%) died. Ventricular fibrillation and myocardial infarction were the causes of death in the early postoperative period in two patients. Two of the remaining three patients died because of cerebrovascular events, and one patient died because of an unknown cause. Ten patients (37%) had been using anticoagulate agents (warfarin) because of concomitant disorders such as deep vein thrombosis, operated valve disease, and arrhythmias. Catheter thrombosis and malfunction was determined in three cases (11.1%). Intra-atrial hemodialysis catheterization is a safe and effective life-saving measure for the patients with multiple venous failure and without any possibility of peritoneal dialysis or renal transplantation.

Three-dimensional gadolinium-enhanced MR venography to evaluate central venous steno-occlusive disease in hemodialysis patients

AIM

To determine the agreement and diagnostic accuracy of three-dimensional gadolinium-enhanced magnetic resonance venography (3D-Gd-MRV) in central venous steno-occlusive disease (CVSD) in haemodialysis patients.

MATERIALS AND METHODS

Fourteen consecutive haemodialysis patients underwent interventional procedures to evaluate or treat CVSD. 3D-Gd-MRV was performed before the procedures and the results were compared with digital subtraction angiography (DSA).

RESULTS

DSA showed >50% stenosis in all 14 patients, 13 of whom were diagnosed correctly using 3D-Gd-MRV. Moderate stenosis was missed at 3D-Gd-MRV in one case whereby the indwelling dialysis central venous catheter may have caused an artefact on the images and hindered the accuracy of the result. The sensitivity of 3D-Gd-MRV in revealing stenosis was 93% (13/14). No complications caused by contrast agent toxicity occurred in any patient.

CONCLUSION

3D-Gd-MRV employing a non-breath-hold technique is highly sensitive in the diagnosis of CVSD and may be an alternative technique to DSA for the visualization of central veins.

Use of covered stents in the central vein: a feasibility study in a canine model

PURPOSE

To evaluate the feasibility of using covered stents vs. bare stents in a model of central vein stenosis with an arteriovenous graft created to mimic the conditions in hemodialysis patients.

METHODS

In 7 mongrel dogs, an expanded polytetrafluoroethylene-covered nitinol stent was placed in one common iliac vein and a bare stent was placed in the contralateral vein. Arteriovenous grafts were created bilaterally between the common femoral artery and vein to induce endothelial damage. Neointima formation in the covered stents was compared to the bare stents at 12 weeks using microscopy and histochemical staining.

RESULTS

Two dogs were excluded due to thrombosis and infection of the arteriovenous grafts, but all stents in the remaining 5 dogs were patent. Smooth, complete neointimal coverage was observed on the inner surface of all the covered stents without intraluminal thrombus. In contrast, incomplete neointimal coverage was seen in all bare stents, with small focal thrombi adhering to the neointima on 3 bare stents. Focal nodular neointimal hyperplasia with denudation of the endothelium was observed in only 2 bare stents. Mean neointimal thickening was significantly greater in the covered stents. Eccentric neointimal thickening was observed at the inflow and outflow segments of both types of stents.

CONCLUSION

Covered stents are technically feasible for the treatment of central vein stenosis, and they demonstrate complete, smooth neointimal coverage in normal central veins, but they also display greater neointimal thickening than bare stents.

Safety of endovascular treatment of chronic cerebrospinal venous insufficiency: a report of 240 patients with multiple sclerosis

PURPOSE

To evaluate the safety of outpatient endovascular treatment in patients with multiple sclerosis (MS) and chronic cerebrospinal venous insufficiency (CCSVI).

MATERIALS AND METHODS

A retrospective analysis was performed to assess complications occurring within 30 days of endovascular treatment of CCSVI. The study population comprised 240 patients; 257 procedures were performed over 8 months. The indication for treatment in all patients was symptomatic MS. Of the procedures, 49.0% (126 of 257) were performed in a hospital, and 51.0% (131 of 257) were performed in the office. Primary procedures accounted for 93.0% (239 of 257) of procedures, and repeat interventions accounted for 7% (18 of 257). For patients treated primarily, 87% (208 of 239) had angioplasty, and 11% (26 of 239) had stent placement; 5 patients were not treated. Of patients with restenosis, 50% (9 of 18) had angioplasty, and 50% (9 of 18) had stent placement.

RESULTS

After the procedure, all but three patients were discharged within 3 hours. Headache after the procedure was reported in 8.2% (21 of 257) of patients; headache persisted > 30 days in 1 patient. Neck pain was reported in 15.6% (40 of 257); 52.5% (21 of 40) of these patients underwent stent placement. Three patients experienced venous thrombosis requiring retreatment within 30 days. Sustained intraprocedural arrhythmias were observed in three patients, and two required hospital admission. One of these patients, who was being retreated for stent thrombosis, was hospitalized because of a stress-induced cardiomyopathy.

CONCLUSIONS

Endovascular treatment of CCSVI is a safe procedure; there is a 1.6% risk of major complications. Cardiac monitoring is essential to detect intraprocedural arrhythmias. Ultrasonography after the procedure is recommended to confirm venous patency and to identify patients experiencing acute venous thrombosis.