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

Risk factors for in-stent restenosis in maintenance hemodialysis patients with central venous occlusive disease and biomechanical assessment of stents

OBJECTIVES

To investigate the risk factors and biomechanical mechanisms of in-stent restenosis (ISR) in central venous occlusive disease (CVOD).

PATIENTS AND METHODS

This retrospective study consecutively included 77 maintenance hemodialysis (MHD) patients with CVOD who received the first percutaneous transluminal angioplasty with stenting (PTS) due to symptomatic CVOD in a tertiary hospital. The mean age was 59.7 ± 14.0 years, and 51.9% of patients were male. The clinical characteristics, occurrence of ISR and patency rates were recorded. Finite element method was applied to assess the biomechanical properties of stents.

RESULTS

Among 77 patients with a mean CVS score of 8.0 ± 2.8, 20.8%, 62.3%, and 16.9% of patients had the main vein of CVOD in the subclavian vein, brachiocephalic vein, and superior vena cava, respectively. A total of 72 (93.5%) patients received successful PTS treatment, for which the stents implanted were mainly Fluency covered stent (48.6%) and SMART bare stent (31.9%). During 15 (10-24)-months of follow-up, ISR occurred in 36.1% of the 72 patients. The primary and assisted primary patency rates at 6, 12, and 18 months were 78%, 56%, 42% and 95%, 90%, 87%, respectively. A prolonged dialysis vintage was an independent risk factor for ISR, yet the stent type or the main vein location was not correlated with ISR. Among three laser-engraving stents, the SMART stent was the best in terms of flexibility, stress, and strain on stents but worst in stress or strain on vessels. The Luminexx stent was the best in radial force and worst in stress or strain on stents. The Vici stent was the best in stress and strain on vessels and worst in radial force and flexibility.

CONCLUSIONS

An unsatisfactory comprehensive biomechanical performance from configurations rooted in existing stents may account for the high incidence of ISR in CVOD.

Outcomes of stent grafts for treatment of central venous disease in hemodialysis patients

BACKGROUND

To evaluate the effectiveness of stent graft (SG) for the treatment of central venous disease (CVD) in hemodialysis patients.

METHODS

Between January 2014 and April 2022, 122 patients on hemodialysis with symptomatic CVD were treated with percutaneous transluminal angioplasty (PTA) and bare-metal stent (BMS) or SG placement. The mean follow-up was 14.5 months (IQR: 8.0, 24.2). Patency rates of the target sites were calculated using Kaplan-Meier and log-rank studies. Multivariate Cox proportional hazard models were used to evaluate the association between various characteristics and target site primary patency.

RESULTS

Technical success rate was 100%. At 3, 6, 12, and 24 months, the target sites primary patency rates were 86.4%, 74.2%, 45.1%, and 30.4% for PTA; 94.7%, 78.6%, 60.8%, and 45.6% for BMS; and 94.0%, 92.0%, 82.4%, and 66.8% for SG, respectively, and the assisted primary patency rates were 86.5%, 80.4%, 63.8%, and 46.0% for PTA; 94.7%, 89.5%, 77.5%, and 71.1% for BMS; 100%, 100%, 97.8%, and 83.4% for SG, respectively. The Kaplan-Meier analysis indicated that SGs achieved better primary and assisted primary patency than PTA or BMS (p<0.05). SG use and concomitant stenosis were the independent predictors of target site primary patency dysfunction in the multivariate analysis.

CONCLUSIONS

This study confirmed the better long-term patency of SG in comparison with PTA and BMS for the treatment of CVD in hemodialysis patients.

Clinical outcome of percutaneous angioplasty and covered stent placement for treatment of left brachiocephalic vein obstruction in hemodialysis patients

BACKGROUND

Left brachiocephalic vein (LBV) obstruction is a common complication in patients undergoing hemodialysis. This study aimed to compare the clinical characteristics and outcomes of patients with LBV obstruction who underwent percutaneous angioplasty or stenting.

METHODS

We performed a retrospective study of 67 hemodialysis patients with LBV stenosis or occlusion who underwent percutaneous transluminal angioplasty (PTA; n = 25) or percutaneous transluminal stenting (PTS; n = 42). We compared the clinical characteristics, lesion features, and patency between the two groups of patients.

RESULTS

The average age, sex, smoking history, body mass index, obstruction period, comorbidities, and clinical manifestations were comparable between the PTA and PTS groups. Prior ipsilateral catheterization was less common in the PTS group than in the PTA group (14.3% vs 36.0%, p < 0.05). Smaller sized balloons were used in the PTS group than in the PTA group (p < 0.05). The overall primary patency rates were similar between the two groups, whereas the secondary patency rate in the PTS group was higher than that in the PTA group (p < 0.05). The average age, sex, smoking history, body mass index, obstruction period, prior ipsilateral catheterization, comorbidities, and types of lesions were comparable between patients with or without restenosis, while patients with restenosis had a higher percentage of high venous pressure than those without restenosis (87.5% vs 60.5%, p < 0.05).

CONCLUSION

The primary patency rates were similar in the angioplasty and the stenting groups. Stenting has a significantly higher secondary patency rate than angioplasty alone for treating LBV obstruction and is required more commonly in patients without prior ipsilateral catheterization.

Small Oversized Stent Graft Is Associated With Increased Patency for the Treatment of Central Venous Disease in Hemodialysis Patients

PURPOSE

The purpose of this study was to identify the independent predictors of higher patency rates and investigate the selection of specifications of stent graft in the treatment of central venous disease.

MATERIALS AND METHODS

This retrospective study included 54 patients who underwent stent-grafts' placement for the treatment of central venous disease between March 2017 and September 2022 at a tertiary hospital. The demographic data for the patients and the clinical data of the treated lesions were collected and analyzed. The patency rates of the treated lesions with different oversizing range were calculated via the Kaplan-Meier and log-rank analyses. The multivariate Cox proportional hazard models were constructed to identify the independent predictor of the target site primary patency.

RESULTS

The median follow-up period was 21.5 months. The primary patency rates of the target sites were 90.7%, 72.2%, and 55.1% at 6, 12, and 24 months, respectively. The assisted primary patency rates of the lesions were 96.3%, 92.5%, and 80.3% at 6, 12, and 24 months, respectively. The log-rank analysis showed that the stent-grafts' placement with small oversizing had significantly higher primary patency rates than those with large oversizing (p=0.022). The multivariate analysis revealed that concomitant stenosis and large oversizing stent graft were the independent predictors of target site primary patency.

CONCLUSIONS

Stent grafts showed reasonable primary patency for the treatment of central venous disease in hemodialysis patients. A stent graft with small oversizing is associated with better target site primary patency rates than those with large oversizing.

CLINICAL IMPACT

Stent grafts showed reasonable primary patency for the treatment of central venous disease in hemodialysis patients. Few studies, however, have explored the efficiency of stent grafts to treat CVD by considering different factors such as sizing considerations, the rate of oversizing percentage, etc. A stent graft with small oversizing is associated with better target site primary patency rates than those with large oversizing. Excessive oversizing should be avoided to prevent infolding or stent collapse.

Complex central venous catheter for dialysis: interventional radiology experience in insertion and management of their complications

BACKGROUND

CVCs are defined 'complex' when they are inserted through non-conventional accesses or positioned in non-usual sites or substituted by IR endovascular procedures. We report our experience in using diagnostic and interventional radiology techniques for complex CVC insertion and management; we recommend some precautions and techniques that could lead to long-term availability of central venous access and to avoid non-conventional sites CVC insertion.

METHODS

We retrospectively evaluated 617 patients, between January 2010 and December 2019, (mean age 71 ± 13; male 448/617), treated in our department for insertion of tunnelled CVC for haemodialysis.

RESULTS

Among 617 patients, 241 cases (39%) are considered 'complex' because they required either a PTA with or without stenting to restore/maintain venous access or had an unusual positioning site or required unconventional access. A direct correlation between CT angiography and PTA (r = 0.95; p-value <0.001) and an inverse correlation between CT angiography and unconventional 'rescue' access (r = -0.92; p-value <0.001) were found.

CONCLUSIONS

Precise pre-operative planning of treatment in a multidisciplinary setting and diagnostic and interventional radiology procedures knowledge allows reducing complex catheterisms in haemodialysis patient.

Central vein stenosis in hemodialysis vascular access: clinical manifestations and contemporary management strategies

Central venous stenosis is a significant and frequently encountered problem in managing hemodialysis (HD) patients. Venous hypertension, often accompanied by severe symptoms, undermines the integrity of the hemodialysis access circuit. In central venous stenosis, dialysis through an arteriovenous fistula is usually inefficient, with high recirculation rates and prolonged bleeding after dialysis. Central vein stenosis is a known complication of indwelling intravascular and cardiac devices, such as peripherally inserted central catheters, long-term cuffed hemodialysis catheters, and pacemaker wires. Hence, preventing this challenging condition requires minimization of central venous catheter use. Endovascular interventions are the primary approach for treating central vein stenosis. Percutaneous angioplasty and stent placement may reestablish vascular function in cases of elastic and recurrent lesions. Currently, there is no consensus on the optimal treatment, as existing management approaches have a wide range of patency rates.

Objective Performance Goals Based on a Systematic Review and Meta-Analysis of Clinical Outcomes for Bare-Metal Stents and Percutaneous Transluminal Angioplasty for Hemodialysis-Related Central Venous Obstruction

PURPOSE

To use safety and efficacy outcomes following treatment with percutaneous transluminal angioplasty (PTA) and/or stent placement for thoracic central venous obstruction in hemodialysis-dependent patients to establish objective performance goals (OPGs).

METHODS

A systematic literature review and meta-analysis were conducted for articles published between January 1, 2000, and August 31, 2021. Efficacy outcomes included primary patency rates at 6 and 12 months, and safety outcomes included adverse events (AEs) categorized as access loss, procedure-related AEs, and serious AEs (SAEs). OPGs were derived from the upper and lower bounds of the 95% confidence intervals for primary patency and SAE rates.

RESULTS

Of 66 articles reviewed, 17 met the inclusion criteria (PTA, n = 4; stent placement, n = 5; PTA/stent, n = 8). The 6- and 12-month primary patency rates for PTA were 50.9% and 36.7%, respectively. Based on these findings, the proposed 6- and 12-month primary patency OPGs identifying superiority against PTA were 66.5% and 52.6%, respectively, and those for noninferiority were 39.0% and 25.7%, respectively. For stent placement, the 6- and 12-month primary patency rates were 69.7% and 47.9%, respectively. The proposed 6- and 12-month primary patency OPGs identifying superiority were 82.1% and 64.1%, respectively, and those for noninferiority were 59.3% and 35.8%, respectively. SAE rates for PTA and stent placement were 3.8% and 8.1%, respectively. Proposed safety OPGs for noninferiority versus superiority for PTA and stent placement were 10.1% versus 1.4% and 13.6% versus 4.8%, respectively.

CONCLUSION

The OPGs derived from real-world studies of PTA and stent placement may serve as a benchmark for future interventions indicated for this patient population.

Most complex brachiocephalic vein occlusion in hemodialysis patients can be treated with simple endovascular techniques in an office-based angiosuite

OBJECTIVE

Brachiocephalic vein (BCV) obstruction can cause dialysis access dysfunction and failure. Central vein stenosis involving the BCV may require advanced endovascular procedures. We report that most BCV occlusions can be treated using simple endovascular techniques on an outpatient basis.

METHODS

From January 2009 to January 2022, 115 hemodialysis patients underwent BCV endovascular revascularization. Seventy-three of the initial procedures were performed in an office-based angiosuite. Indications for the procedure were BCV occlusion endangering the performance of a previous arm access or making the creation of a new arm access unadvisable. We recorded and analyzed risk factors and procedural results, patency rates, complications, and mortality.

RESULTS

The median age was 62 years (range, 23-91 years); 56% were female. Most prevalent associated conditions were diabetes mellitus (61%) and hypertension (68%). Fifty-six patients (48.7%) presented with severe upper extremity edema ipsilateral to the side of pre-existing functioning access. Obstruction recanalization was effective using standard catheter and wire in 106 cases (92.1%) and transseptal needle in nine cases (7.8%), that included seven using inside-out procedure. Initial management of the BCV stenosis was percutaneous transluminal balloon angioplasty alone in 74 patients (64.3%), stenting in 33 (28.7%), and HeRO conduit in eight cases (7%). Treatment of other central venous lesions included 49 cases (42.6%). The procedure was successful in 99.1% of patients. No intraoperative complications occurred. All 92 patients with previous arm access maintained adequate performance (100%). In 22 of 23 patients (95.6%), new upper extremity access creation was effectively performed after the venous intervention. Overall clinical success rate was 92%. The mean postoperative monitoring was 23 months, the median was 12 months, and the range was 1 to 84 months. During this monitoring period, 266 endovascular procedures, 91% in the office and 9% in the hospital, were required to preserve access performance. Eventually, 49 patients (42.6%) were stented. Eleven patients (9.56%) had infections, and six required complete access removal. Other causes of access failure included two patients with central vein thrombosis and one with massive pulmonary embolus. At the end, nine patients (7.8%) had access failure. Thirty-two patients (27.8%) died of unrelated causes during the follow-up period. Seventy-six patients (66%) have maintained functional access. Kaplan-Meier curves determined median primary patency of 9.6 months, median primary assisted patency of 56.2 months, and secondary patency of 75% at 80 months.

CONCLUSIONS

Successful endovascular revascularization of BCV obstruction can be treated safely, with simple endovascular techniques in an office-based context with minor complication rates and durable results.

The role of stents in hemodialysis vascular access

Vascular access is the Achilles' heel of dialysis therapy among patient with end stage kidney disease. The development of neointimal hyperplasia and subsequent stenosis is common in vascular access and is associated with significant morbidity. Percutaneous transluminal angioplasty using balloon inflation was the standard therapy of these lesions. However, the balloon-based approaches were associated with poor vascular access patency rate necessitating new inventions. It is within this context that different types of stents were developed in order to improve the overall dialysis vascular access functionality. In this article, we review the available literature regarding the use of stents in treating dialysis vascular access stenotic lesions. Further, we review the major clinical trials of stent use in different anatomic locations and in different clinical scenarios.

Long-Term Outcome of a "Mother-Child" Coaxial Dual-Catheter Technique for Percutaneous Transluminal Angioplasty of Central Vein Stenosis or Occlusion in Hemodialysis Patients

PURPOSE

This study aims to evaluate the long-term outcome and prognostic factors of a "mother-child" coaxial dual-catheter technique for percutaneous transluminal angioplasty (PTA) in the treatment of central vein stenosis (CVS) or central vein occlusion (CVO).

MATERIALS AND METHODS

During September 2017 to August 2020, totally, 76 hemodialysis patients with symptomatic CVS or CVO were treated with PTA using the mother-child technique. The success rate, complications, and follow-up information were collected. Cox proportional hazard analysis was used to explore the predicting factors of primary patency. Primary patency rates of different subgroups were generated with the Kaplan-Meier analysis and compared using the log-rank (Mantel-Cox) test.

RESULTS

There were 31 CVS patients and 45 CVO patients who presented with 114 PTAs. The initial procedure success rate was 98.25%. By the end of the follow-up, 57 patients (75%) had maintained functioning fistula after initial or repeated PTAs. The primary patency rates were 88.75% at 3 months, 73.36% at 6 months, 55.83% at 12 months, and 50.75% at 18 months. The secondary patency rates were 97.14% at 6 months, 87.66% at 12 months, and 82.18% at 24 months. The predictors for primary patency were history diabetes mellitus (hazard ratio [HR] = 3.1, 95% confidence interval [CI]: 1.31-7.30, P = .010), abnormal white blood cell count (HR = 1.44, 95% CI: 1.18-1.75, P < .001), lesion at subclavian-innominate vein (HR=2.75, 95% CI: 1.34-5.63, P = .006), and occlusion (HR=0.33, 95% CI: 0.14-0.76, P = .010). The primary patency was significantly lower in the subclavian-innominate vein subgroup, with a median primary patency of 4.5 (3-12.75) months, than in the nonsubclavian-innominate vein subgroup (8.5 [5-13] months; P = .005). The median duration of each PTA was 8 months for the first PTA, 7.5 months for the second PTA, and 5 months for the third PTA. There was no significant difference in the patency duration of repeated PTAs and the primary PTA (P = .389).

CONCLUSIONS

The mother-child coaxial dual-catheter technique has a good success rate and acceptable primary patency in the treatment of hemodialysis patients with CVS or CVO. Repeated PTA is as effective as the primary PTA.

CLINICAL IMPACT

This is the follow up report on the "Mother-Child" coaxial dual-catheter technique for percutaneous transluminal angioplasty of central vein stenosis or occlusion in hemodialysis patients since we first presented it in 2019. In this paper, we can see that the long-term patency rate of this technique for central venous disease is satisfactory, and repeated use of this technique does not affect the patency time. Compared with other literature reports, the surgical success rate of this technique is significantly improved. Therefore, this technique is worth popularizing in the treatment of central venous disease.

Kissing Viabahn VBX stent graft reconstruction of thoracic central veins for management of superior vena cava syndrome

OBJECTIVE

In the present study, we evaluated the technical and clinical outcomes of thoracic central vein reconstruction for superior vena cava (SVC) syndrome using kissing Viabahn VBX stent grafts (W.L. Gore & Associates, Flagstaff, AZ).

METHODS

All adult patients with SVC syndrome who had undergone attempted bilateral brachiocephalic vein-to-SVC reconstruction using kissing VBX stent grafts at an academic hospital between August 2019 and February 2021 were reviewed. The technical results, adverse events, imaging follow-up findings, and clinical outcomes were recorded. Patency over time was assessed using Kaplan-Meier analysis.

RESULTS

A total of 28 patients (16 women and 12 men; mean age, 52.0 years) constituted the study cohort. Of the 28 patients, 17 (60.7%) had had benign and 11 (39.3%) malignant etiologies. The presenting symptoms included neck swelling (n = 17; 60.7%), bilateral upper extremity swelling (n = 15; 53.6%), dyspnea (n = 7; 25%), unilateral upper extremity swelling (n = 4; 14.3%), and dysphagia (n = 1; 3.6%). SVC reconstruction with VBX stent grafts in a kissing configuration was successfully completed in 27 of the 28 patients (96.4%). Four major adverse events were noted in the benign etiology subgroup (23.5%), including intraprocedural hemopericardium (n = 3) and delayed pneumothorax (n = 1). Of the 28 patients, 27 (96.4%) had experienced resolution of their presenting symptoms. The mean clinical follow-up for the living patients was 358.8 ± 77.2 days (range, 78-645 days). The mean imaging follow-up for the living patients was 272.6 ± 91 days (range, 26-594 days). The primary, primary-assisted, and secondary patency rates at 12 months were 71.8%, 88.8%, and 100%, respectively.

CONCLUSIONS

For the management of SVC syndrome, thoracic central vein reconstruction with kissing VBX stent grafts was feasible with a high rate of symptom resolution and acceptable patency. However, this technique should not be recommended for those with benign SVC syndrome owing to the high risk of cardiac tamponade.

One-year outcomes and predictive factors for primary patency after stent placement for treatment of central venous occlusive disease in hemodialysis patients

Objective:

The study purpose was to determine the outcomes and factors predictive of primary stent patency for the treatment of central venous occlusive disease (CVOD) in hemodialysis patients.

Methods:

Data of 71 patients with CVOD treated with stent placement from January 2012 to December 2017 were analyzed. Univariate and multivariate analysis was performed to determine factors associated with stent patency. Adverse events related to stent placement were also examined.

Results:

The median primary patency duration of the 71 patients was 16 ± 2.2 months. The cumulative 3-, 6-, 9-, and 12- month primary patency rates were 93%, 72%, 55%, and 51%, respectively. Independent predictors of longer primary patency were vessel diameter > 12 mm, the use of a covered stent, and absence of vessel calcifications. Median primary patency of covered stents was 21 months as compared with only 10 months for bare stents (p < 0.001). Procedure-related adverse events occurred in 17 patients (21.8%), and four events (5.1%) required medical intervention. No life-threaten complications occurred.

Conclusions:

A vessel diameter > 12 mm, the use of a covered stent, and no vessel calcifications are independently associated with a higher primary patency rate after treatment of CVOD in hemodialysis patients.

Insights Into Endovascular Management of Superior Vena Cava Obstructions

Superior vena cava obstruction results from any limitation of blood flow through the superior vena cava. Circulation to the heart may persist through various collateral vessels whose development depends on the level of obstruction. Depending on the level and degree of occlusive disease, the severity of clinical symptoms may vary considerably, up to lethal. Etiologies have changed dramatically in recent years, mainly due to the increasing use of intravascular devices. However, guidelines for treatment are lacking, and various options are available. Endovascular therapies developed considerably in recent years, may offer a rapid improvement in symptoms and proved to be safe. However, knowledge and selection of appropriate techniques are essential to venous angioplasty, involving specific tools to guarantee satisfying outcomes. This review aims to discuss the particular venous anatomy of the upper body, the physiopathology of superior vena cava obstruction, and specificities of endovascular treatment compared with other management options.

Comparison of Management for Central Venous Stenosis With or Without Previous Catheter Placement

Objective: To compare central venous stenosis/occlusion with or without previous jugular catheter placement history.

Methods: Data of patients with central vein stenosis/occlusion receiving endovascular intervention in our hospital from January 2015 to December 2018 were collected and analyzed.

Results: Twenty-nine patients with previous jugular catheter placement history (CVC group) and 33 patients (excluded two with technical failure) without such history (non-CVC group) are included in this study. Previous jugular catheter placement history raised the risk of postintervention recurrence 1.02 times (CVC group vs. non-CVC group, HR = 2.02 95%CI: 0.91–4.48). The primary patency rate at 6, 12, 18, and 24 months was 76.9, 54.2, 45.5, and 25.0% separately in the CVC group and 80.6, 70.0, 67.9, and 44.4% separately in the non-CVC group. The assisted primary patency rate at 6, 12, 18, and 24 months was 92.3, 91.7, 86.4, and 68.8% separately in the CVC group and 93.5, 90.0, 82.1, and 61.1% separately in the non-CVC group. Patients in the CVC group received a higher frequency of reintervention (0.7 times/year/patient vs. 0.3 times/year/patient). There was no significant difference in the assisted primary patency rate between the two groups. Different primary interventions (angioplasty alone, bare metal stent, stent graft) did not affect primary patency and assisted primary patency, but percutaneous transluminal stenting (PTS) with a bare metal stent had a significant lower primary patency rate between 3 and 24 months compared with PTS with a stent graft (p = 0.011).

Conclusion: Central venous stenosis/occlusion with a previous jugular catheter placement history develops symptoms earlier and had a worse prognosis after endovascular intervention. More efforts are needed to carry out end-stage kidney disease life plan to reduce the harm of evitable catheter placement.

A systematic review of venoplasty versus stenting for the treatment of central vein obstruction in ipsilateral hemodialysis access

OBJECTIVE

This review examines the evidence regarding treatment of central vein obstruction (CVO) in the setting of ipsilateral hemodialysis access. The aim of this work is to identify whether long-term venous patency after central vein stenting is superior compared with balloon venoplasty. To date, there are no evidence-based guidelines to direct the management of CVO in the setting of ipsilateral hemodialysis access.

METHODS

An extensive systematic database search was performed using Medline, Embase, and the Cochrane Databases to identify all articles published from January 2000 to November 2019 comparing the management of CVO with venoplasty and/or stenting in the setting of ipsilateral hemodialysis access fistulae/grafts.

RESULTS

There were 655 patients with 456 stenoses and 208 occlusions who were treated; 288 underwent venoplasty and 345 underwent stenting. Twenty-two patients failed intervention owing to an inability to traverse the occlusion. The most affected vein was the brachiocephalic vein. A superior primary patency (PP) is noted in those treated with stenting compared with venoplasty in the first 2 years. Overall, both treatments are suboptimal demonstrating a 12-month PP rate of less than 60%. Assisted PP and secondary patency rates were similar for both venoplasty and stenting with a 12-month secondary patency rate of 77.8% to 91.6% for venoplasty and 89.6% to 98.4% for stenting. Periprocedural and long-term complications were rare for both interventions, occurring in 2% of patients.

CONCLUSIONS

Although both treatments demonstrated poor patency rates, greater PP is noted for stenting in the first 2 years. Coupled with low complication rates, this finding highlights a potential benefit of stenting as a first-line treatment for CVO. Allowing for the overall poor quality of current studies, even this short-term improvement in PP may benefit patients undergoing hemodialysis. Further research with randomised control trials as well as assessment of adjuvant techniques such as drug-coated stents and balloons, anticoagulant therapy, and the role of intravascular ultrasound use is required.

[Complications of permanent vascular access for haemodialysis]

Permanent vascular access is the basis of renal replacement therapy by the method of programmed haemodialysis, on whose stable functioning depends the life of patients with end-stage renal disease. At the present time, there is significant deficit of scientific and methodological Russian-language literature on this problem, with no Russian consensus documents concerned. This article is a review of the contemporary world literature dedicated to the problem of permanent vascular access, including currently in force European (2018) and North American (2019) guidelines for good clinical practice, also discussing the problems of strategy and tactics of creating a permanent vascular access, monitoring its dysfunction, pathophysiology of functioning of arteriovenous fistulas. Presented herein are unified approaches to diagnosis and treatment of thrombolytic and haemorrhagic complications associated with the access, as well as local infectious and non-infectious complications. Special attention is paid to indications for the operation and rational therapeutic decision-making.

Efficacy and safety of recanalization with transseptal needle for chronic total occlusion of the brachiocephalic vein in hemodialysis patients

Background

Whilst there are effective techniques for the recanalization of central venous occlusions, recanalization of chronic total occlusions remains particularly challenging. This study aims to evaluate the safety and efficacy of recanalization using a transseptal needle in chronic total occlusions of the right brachiocephalic vein (RBV) in long-term hemodialysis patients.

Methods

In this single-center, retrospective study, maintenance hemodialysis patients with chronic total occlusion of the RBV were enrolled between February 2017 to March 2019 from West China Hospital of Sichuan University. Refractory lesions were defined as complete vascular occlusions with failed recanalization using conventional techniques. Occlusions were approached using a transseptal needle to penetrate which offers an alternative strategy with firm support force. Patient data, treatment outcomes and patency rates were collected and analyzed to assess the safety and efficacy of the technique.

Results

A total of 16 eligible patients were analyzed. The operation was successful in 13 of the 16 patients and the success rate was 81.25% (13/16). Twelve patients underwent percutaneous balloon dilatation and stent implantation after sharp recanalization, whilst one patient underwent balloon dilatation only. We achieved procedural success in 13 patients without surgical complications, and all of the patients were discharged in a stable condition. The primary patency rates at 3, 6 and 12 months after surgery were 100%, 84.6% and 69.2%, respectively. The primary assisted patency rates were 100%, 84.6% and 76.9%, respectively, and the secondary patency rates were 100%, 84.6% and 76.9%, respectively.

Conclusions

This study demonstrates that recanalization of chronic total occlusions to the RBV using a transseptal needle is a safe and effective method after traditional guide wire and catheter techniques fail. It was also found that additional techniques are needed for recanalization in patients with RBV occlusion combined with proximal stenosis or occlusion of the right subclavian vein.

Outcomes of the Gore Excluder abdominal aortic aneurysm leg endoprosthesis for treatment of central vein stenosis or occlusion in patients with chronic hemodialysis

OBJECTIVE

Central venous occlusive disease is a critical complication in long-term hemodialysis patients with arteriovenous (AV) dialysis circuits. The purpose of this retrospective, single-arm cohort study was to evaluate the effectiveness of an abdominal aortic aneurysm (AAA) contralateral leg endoprosthesis to treat symptomatic central venous occlusive diseases in patients with chronic hemodialysis.

METHODS

A prospective cohort study included 60 patients on hemodialysis presenting with central venous stenosis or occlusion, who were treated with a Gore Excluder AAA contralateral leg stent graft between December 2013 and July 2018. Follow-up angiography was obtained at 3, 6, and 12 months. The outcomes and duration of primary circuit and target site patency were measured from the time of the stent graft implantation to the first reintervention for AV circuit dysfunction and target site restenosis. Secondary patency was calculated from stent graft implantation to the point when AV access was no longer attainable.

RESULTS

Circuit primary patency rate was 54.9% at 1 year of Gore Excluder AAA contralateral leg or iliac extender stent grafts, implanted in 60 hemodialysis patients with central vein occlusive disease. Cumulative target site primary patency rate was 88.3% at 1 year. Secondary patency rate was 95% during follow-up. Patients with concomitant lesions had a significantly higher risk of circuit primary patency dysfunction.

CONCLUSIONS

Treatment of central vein obstructions in hemodialysis patients with stent grafts has been appealing owing to the tapered shape with a larger diameter and the availability of various lengths.

Comparison of Percutaneous Transluminal Angioplasty with Stenting for Treatment of Central Venous Stenosis or Occlusion in Hemodialysis Patients: A Systematic Review and Meta-analysis

OBJECTIVES

A common cause of hemodialysis vascular access dysfunction, a primary cause of morbidity and mortality in patients undergoing hemodialysis, is central venous stenosis or occlusion. The present study compared percutaneous transluminal angioplasty (PTA) with percutaneous transluminal angioplasty and stent placement (PTS) for treatment of central venous stenosis or central vein occlusion in hemodialysis patients.

METHODS

A systematic literature review was conducted using database searches of PubMed, Cochrane, and Embase. Articles were selected using the Population/Intervention/Comparator/Outcomes (PICO) process. Outcomes included the rate of procedural success, primary patency, assisted primary patency, re-intervention subjects, re-intervention rate, and adverse events.

RESULTS

A total of eight studies were included in the meta-analysis with subjects in the PTA group (n = 281) or PTS group (n = 192). Primary patency rate between PTA and PTS groups at 3-, 6-, 12-, or 24-month follow-up was not different (all p > 0.05). Patients treated with PTA had greater assisted primary patency rates than the PTS group (OR = 1.03, 1.73, 1.03, and 2.00 at 3, 6, 12, and 24 months, respectively). However, the statistical assessment only showed significantly at 24-month follow-up (p = 0.01).

CONCLUSIONS

The present meta-analysis revealed that, compared to PTS, PTA may provide increased assisted primary patency for endovascular treatment of central vein stenosis or occlusion in patients undergoing hemodialysis.

LEVEL OF EVIDENCE

Level 3a.

Site of service influence on stent use for hemodialysis access interventions

OBJECTIVE

With rising health care spending in the United States, the Centers for Medicare and Medicaid Services (CMS) in recent years attempted to use reimbursement rates to influence use of less expensive care sites for covered patients, such as ambulatory surgery centers (ASCs) and office-based laboratories (OBLs), in lieu of hospital service sites. It has been suggested that cost savings have not been realized because of more procedures being performed by physicians with ownership interests in nonhospital facilities. CMS adopted massive reimbursement changes for 2019 OBL and ASC-based procedures, which reduced dialysis access angioplasty reimbursement in the ASC setting by 50%, whereas facility reimbursement for stenting increased by 33% above prior levels. The clinical utility of adjunctive stenting in treating dialysis access stenosis remains controversial and highly discretionary. As a vascular group performing such procedures in both a hospital and nonhospital facility in which we have equity interest, we reviewed our use of stents in dialysis access procedures both in the hospital and in the ASC/OBL to determine whether site of service affected stent use.

METHODS

A retrospective review of a prospectively maintained database was performed from 2014 to 2018. All patients undergoing dialysis access angiography with angioplasty and adjunctive stent placement at our OBL (later ASC) and our primary hospital were included in the study.

RESULTS

There were 961 angioplasty or stent procedures performed for dialysis accesses between the two sites, 564 (58.7%) in the hospital setting and 397 (41.3%) at the OBL/ASC. There was a significant difference in race and age between the two sites, with younger, minority patients more frequently being treated in the hospital and older, white patients more likely to be treated in the ambulatory setting; 153 (27.1%) underwent adjunctive stent placement in the hospital and 127 (32.0%) in the ambulatory setting (P = .09).

CONCLUSIONS

Whereas financial incentives have not yet had an appreciable influence on stent use for dialysis access within previous reimbursement paradigms, the dramatic changes recently adopted by CMS may well alter this dynamic and could lead to substantially higher overall costs without proven clinical advantage. Interventionalists may be incentivized to add stents when performing balloon angioplasty in ASCs. With high failure and reintervention rates and increasingly expensive adjuncts (drug-coated balloons and stents, covered stents), the cost implications of attempts to incentivize interventionalists toward a specific type of procedure or site of care are substantial, and unintended negative consequences are likely to occur.

Central venous disease in hemodialysis patients

Central venous disease (CVD) is difficult to treat and often resistant to treatment. In CVD, hemodialysis vascular access should sometimes be abandoned, or in serious cases, the patient's life may be threatened. Therefore, prevention is ideal. However, as the prevalence of chronic kidney disease (CKD) has increased steadily with population aging, CKD patients with a peripherally inserted central catheter (PICC) are encountered frequently. PICCs can cause CVD, and the basilic vein, which is regarded as the important last option for native arteriovenous fistula (AVF) creation in end-stage renal disease (ESRD) patients, is destroyed frequently after its use as the entry site of PICC. The most well-established risk factors for CVD are a history of central venous catheter (CVC) insertion and its duration of use. Therefore, to reduce the incidence of CVD, catheterization in the central vein (CV) should be minimized, along with its duration of use. In this review, we will first explain the basic territories of the CV and introduce its pathophysiology, clinical features, and advanced treatment options. Finally, we will emphasize prevention of CVD.

Outcomes of Central Venoplasty in Haemodialysis Patients

Objective: To review the outcomes of central venoplasty in the treatment of symptomatic central vein stenosis in patients undergoing haemodialysis via an ipsilateral arteriovenous fistula (AVF).

Methods: Data were collected retrospectively, and included all the consecutive cases of central venoplasty between January 2008 and December 2015.

Results: A total of 132 central venoplasties in 76 patients were performed, with incidence of symptomatic central vein stenosis at 7.4%. Of the patients, 66% were male and the mean age was 61 years. The most frequent indication was decreased dialysis access flow rates (58%) and 52% of all the patients had symptoms of upper limb swelling. The patients who had previous ipsilateral tunneled internal jugular vein dialysis catheters made up 58% of the patients. The mean time from AVF creation to first central venoplasty was 24 months, and 74% of the cases required a second central venoplasty and the mean time to second venoplasty was 7 months. The overall post intervention assisted primary patency rate was 87%, 74%, 63%, and 42% at 6, 12, 18, and 24 months respectively. Statistically significant differences were found in primary assisted patency (p=0.025) and time to second procedure (p=0.039) comparing those with and without a history of ipsilateral tunneled dialysis catheter.

Conclusion: Central venoplasty is technically feasible with low procedural risk. The maintenance of the AVF patency usually requires multiple procedures at average interval of 7 months. Patients with a history of upper limb tunneled dialysis catheter ipsilateral to the side of central vein stenosis or AVF have a less favorable outcome compared to those without.

Role of stents in hemodialysis vascular access

Stents are ubiquitously utilized in coronary and peripheral arterial disease. Interventional nephrologists, however, place stents in the venous outflow of the arteriovenous access. Stenosis is the predominant pathology that causes access dysfunction and will ultimately lead to thrombosis if uncorrected. Angioplasty and stent deployment are the current techniques available to combat stenosis. From initial bare metal stainless steel stents, the current generations of stents used are predominately covered nitinol stents. The latest randomized control trials reveal that stents decrease the number of interventions required to maintain patency but do not improve the overall access survival. Furthermore, bare metal stents have been shown to be inferior to stent grafts. This review discusses indications for stent deployment in the hemodialysis access, the current evidence for their use, and briefly touches on their complications.

Endovascular stent-based revascularization of malignant superior vena cava syndrome with concomitant implantation of a port device using a dual venous approach

PURPOSE

The aim of this paper is to evaluate the safety and efficacy of endovascular revascularization of malignant superior vena cava syndrome (SVCS) and simultaneous implantation of a totally implantable venous access port (TIVAP) using a dual venous approach.

MATERIALS AND METHODS

Retrospectively, 31 patients (mean age 67 ± 8 years) with malignant CVO who had undergone revascularization by implantation of a self-expanding stent into the superior vena cava (SVC) (Sinus XL®, OptiMed, Germany; n = 11 [Group1] and Protégé ™ EverFlex, Covidien, Ireland; n = 20 [Group 2]) via a transfemoral access were identified. Simultaneously, percutaneous access via a subclavian vein was used to (a) probe the lesion from above, (b) facilitate a through-and-through maneuver, and (c) implant a TIVAP. Primary endpoints with regard to the SVC syndrome were technical (residual stenosis < 30%) and clinical (relief of symptoms) success; with regard to TIVAP implantation technical success was defined as positioning of the functional catheter within the SVC. Secondary endpoints were complications as well as stent and TIVAP patency.

RESULTS

Technical and clinical success rate were 100% for revascularization of the SVS and 100% for implantation of the TIVAP. One access site hematoma (minor complication, day 2) and one port-catheter-associated sepsis (major complication, day 18) were identified. Mean catheter days were 313 ± 370 days. Mean imaging follow-up was 184 ± 172 days. Estimated patency rates at 3, 6, and 12 months were 100% in Group 1 and 84, 84, and 56% in Group 2 (p = 0.338).

CONCLUSION

Stent-based revascularization of malignant SVCS with concomitant implantation of a port device using a dual venous approach appears to be safe and effective.

Viabahn stent for hemodialysis shunt: efficacy, long segment recanalization and prognostic factors for reintervention

INTRODUCTION

The study evaluated the Heparin Bioactive Surface (HBS) Viabahn Stent (W.L. Gore & Associates, Flagstaff, Arizona) efficacy in the maintenance or re-establishment of hemodialysis.

MATERIALS AND METHODS

Fifty HBS Viabahn stents deployed in 37 consecutive patients with hemodialysis dysfunction from January 2008 to May 2016 were evaluated in a single-institution retrospective review. Outcomes were stent patency intended as primary circuit patency (PP), assisted primary patency (APP), target lesion primary patency (TLPP) and secondary patency (SP). Moreover, the risk factor analysis for hemodialysis dysfunction that required reintervention was performed. A subgroup analysis was conducted to assess patency of Viabahn stent to treat peripheral venous long segment obstruction (LSO).

RESULTS

Overall Kaplan-Meyer PPs were 60% at 12 months and 42% at 24 months. Overall TLPP estimated rates were 68% and 49% at 12 and 24 months, respectively. The corresponding SP rates were 85% and 78% at the same period. Estimated PP rates at 12 and 24 months for stent placement after peripheral venous long segment recanalization procedure were 53% and 31%, respectively. Corresponding SP rates were 82% and 68%, respectively. The APP rates were 79% at 12 months and 61% at 24 months. Female sex, access age and thrombosis were associated with reduced primary patency.

CONCLUSIONS

Considering the high rates of PP, TLPP, APP and SP, Viabahn stents have been proven effective in maintaining or re-establishing the hemodialysis access. Moreover, stent placement after recanalization of LSO of venous out-flow represented a valid approach to rescue a dysfunctional fistula that would otherwise be abandoned.