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

Safety and Performance of a Cell-Impermeable Endoprosthesis for Hemodialysis Vascular Access Outflow Stenosis: A Brazilian Multicenter Retrospective Study

PURPOSE

To evaluate the safety and performance of Wrapsody™, a cell-impermeable endoprosthesis (CIE), for treating hemodialysis vascular access outflow stenosis.

MATERIALS AND METHODS

Investigators retrospectively analyzed 113 hemodialysis patients treated with a CIE (11/2021-12/2022) across four centers in Brazil. De novo or restenotic lesions were treated. The primary efficacy outcome measure was target lesion primary patency (TLPP) at 1, 3, 6, and 12 months; the primary safety outcome measure was the absence of serious local or systemic adverse events within the first 30 days post-procedure. Secondary outcome measures included technical and procedural success, access circuit primary patency (ACPP), and secondary patency at 1, 3, 6, and 12 months post-procedure.

RESULTS

Thirty-nine patients (34.5%) had thrombosed access at the initial presentation, and 38 patients (33.6%) presented with recurrent stenosis. TLPP rates at 1, 3, 6, and 12 months were 100%, 96.4%, 86.4%, and 69.7%, respectively. ACPP rates were 100% at 1 month, 89.2% at 3 months, 70.9% at 6 months, and 56.0% at 12 months. The target lesion secondary patency rates at 1, 3, 6, and 12 months were 100%, 97.3%, 93.6%, and 91.7%, respectively. In the adjusted multivariate Cox regression analysis, male sex and endoprosthesis with diameters of 10, 12, 14, and 16 mm were associated with improved primary patency rates. No localized or systemic serious adverse event was observed through the first 30 days post-procedure.

CONCLUSION

The CIE evaluated in this study is safe and effective for treating peripheral and central outflow stenoses in hemodialysis vascular access.

LEVEL OF EVIDENCE

Level 2b, cohort study.

A Systematic Review and Meta-analysis of 24 Month Patency After Endovenous Stenting of Superior Vena Cava, Subclavian, and Brachiocephalic Vein Stenosis

OBJECTIVE

This systematic review and meta-analysis aimed to appraise recent evidence assessing patency outcomes at various time points in patients with superior vena cava, subclavian, and brachiocephalic vein stenosis who had undergone stenting.

DATA SOURCES

PubMed, Scopus, and Cochrane Library databases were searched for studies up to December 2022.

REVIEW METHODS

Measured outcomes included technical success rate, primary, primary assisted, and secondary patency at various time points. A subgroup analysis was also conducted to compare malignant and benign obstruction. GRADE was used to assess the certainty of evidence.

RESULTS

Thirty nine studies reporting outcomes in 1 539 patients were included in the meta-analysis. Primary patency up to one year after the procedure was 81.5% (95% CI 74.5 - 86.9%). Primary patency declined after one year to 63.2% (95% CI 51.9 - 73.1%) at 12 - 24 months. Primary assisted patency and secondary patency at ≥ 24 months were 72.7% (95% CI 49.1 - 88.0%) and 76.6% (95% CI 51.1 - 91.1%). In the subgroup analysis, primary patency was significantly higher in patients with a malignant stenosis compared with a benign stenosis at 1 - 3 and 12 - 24 months. No significant difference was seen for pooled secondary patency rates when comparing the malignant and benign subgroups. GRADE analysis determined the certainty of evidence for all outcomes to be very low.

CONCLUSION

Stenting is an effective intervention for benign and malignant stenosis of the superior vena cava, subclavian, and brachiocephalic veins. Primary patency rates were good up to one year after the procedure, with 81.5% of stents retaining patency at 6 - 12 months. Patency rates declined after one year, to 63.2% primary and 89.3% secondary patency at 12 - 24 months, showing improved outcomes following re-intervention. High quality evidence is lacking. More research is needed to investigate patency outcomes and the need for surveillance or re-intervention programs.

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.

The outcome of sharp recanalization of chronic central venous occlusions in patients undergoing hemodialysis

BACKGROUND

Patients on hemodialysis are particularly vulnerable to central venous occlusion (CVO). Endovascular treatment has gained wide acceptance for the treatment of CVO. However, difficulties in crossing the occluded segment can be encountered during conventional endovascular management. Sharp recanalization has been adopted when conventional endovascular methods could not recanalize the obstructed region. This study aimed to assess the outcome of the sharp venous recanalization technique with angioplasty and stenting in the treatment of CVO in Egyptian patients undergoing hemodialysis.

METHODS

This retrospective study is based on data from a prospectively maintained department database of patients under regular hemodialysis who underwent the sharp venous recanalization technique for CVO. Routinely, the patients were followed up at 3, 6, and 12 months with a clinical examination. The primary outcomes were technical success and primary patency. Secondary outcomes included complication rates and clinical success.

RESULTS

This study included 40 patients. Thirty-six patients (90%) achieved technical and clinical success. Seven patients (17.5%) had immediate postoperative complications. Four cases had minor complications (10%) and three patients had major complications (7.5%): hemothorax in two patients (5.1%) and pneumothorax in one patient (2.6%). At the 1-year follow-up, reintervention was required in nine patients (22.5%), with primary patency rate of 77.5% and a secondary patency rate of 100%.

CONCLUSIONS

Sharp recanalization offers a solution for patients undergoing hemodialysis who developed CVO and failed to be recanalized using the conventional endovascular method. It offered promising technical success, clinical improvement, and good primary patency rates.

Management with right atrium to jugular and brachiocephalic vein bypass for dialysis catheter-related superior vena cava syndrome

Superior vena cava (SVC) syndrome is a spectrum of potentially life-threatening clinical manifestations resulting from either partial or complete obstruction of central venous blood flow. Approximately 70% of cases are caused by malignancy. The primary treatment end point for SVC syndrome is the achievement of long-term patency of the SVC. Malignant SVC syndrome is managed by either radiation therapy, open surgical intervention, or endovascular therapy with angioplasty and stenting. The current report describes an uncommon case of nonmalignant SVC syndrome resulting from complications of hemodialysis catheters that was managed with open revascularization between the right internal jugular and brachiocephalic veins and the right atrium.

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.

The Use of Viatorr Stent at the Thoracic Outlet to Maintain Hemodialysis Access Function

PURPOSE

Venous steno-occlusive disease at the thoracic outlet affects up to 30% of the hemodialysis population [1] causing arm swelling and hemodialysis access dysfunction. Balloon angioplasty in this region can be of limited utility given the rigid compressive effect of surrounding musculoskeletal (MSK) structures. Outcomes of using the Viatorr endoprosthesis (Gore Viatorr TIPS Endoprosthesis, Gore, Flagstaff AR, USA, Viatorr ®) within this region to salvage the HD access in patients who presented with dialysis access dysfunction is presented.

METHODS

A retrospective chart review was performed of our tertiary and quaternary care hospital system. Hemodialysis patients were included in the study if they were using an upper extremity arteriovenous fistula or graft for access, had a Viatorr stent placed in the central (subclavian and/or brachiocephalic) veins, and had follow up.

RESULTS

A total of nine patients were identified to meet the inclusion criteria. Four interventions were due to refractory lesions of the subclavian or brachiocephalic veins, and the other five interventions were for hemodynamically significant lesions refractory to angioplasty alone, all resulting in access dysfunction. Primary patency ranged from 36-442 days (geometric mean 156.6 days, range 19-442 days). No stent fracture was identified on imaging at any point during follow-up of these patients out to a maximum of 2912 days (Average 837 days).

CONCLUSIONS

The Viatorr stent graft used in the HD population for clinically significant lesions at the thoracic outlet (TO) showed no structural failures (fractures) in this cohort.

ACR Appropriateness Criteria® Dialysis Fistula Malfunction

The creation and maintenance of a dialysis access is vital for the reduction of morbidity, mortality, and cost of treatment for end stage renal disease patients. One's longevity on dialysis is directly dependent upon the quality of dialysis. This quality hinges on the integrity and reliability of the access to the patient's vascular system. All methods of dialysis access will eventually result in dialysis dysfunction and failure. Arteriovenous access dysfunction includes 3 distinct classes of events, namely thrombotic flow-related complications or dysfunction, nonthrombotic flow-related complications or dysfunction, and infectious complications. The restoration of any form of arteriovenous access dysfunction may be supported by diagnostic imaging, clinical consultation, percutaneous interventional procedures, surgical management, or a combination of these methods. This document provides a rigorous evaluation of how variants of each form of dysfunction may be appraised and approached systematically. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

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.

Surgical Referral for Hemodialysis Access Maintenance

Hemodialysis access is the lifeline for end-stage renal disease patients. However, dialysis access is associated with a host of complications, including thrombosis, recurrent stenosis, infection, aneurysmal changes and bleeding. Although endovascular therapy remains the first-line treatment owing to its less invasive nature, there are certain situations where surgical referral is recommended or even necessary. Regardless, management of dialysis access complications requires a multidisciplinary approach. Interventional radiologists should be familiar with the appropriate timing for surgical referral to better serve the complex patient population.

Dialysis access graft occlusion with contrast and ultrasound guided thrombin injection for intractable arm edema and pseudoaneurysm

We present the case of a patient with a brachio-basilic graft forearm loop with intractable edema and thrombosed central veins. She showed up with an important edema after some effort and a previously thrombosed pseudoaneurysm with significant growth. She refused angioplasty treatment for central veins, the graft had not been used for dialysis during the last year, so that arteriovenous graft (AVG) ligation was considered. Due to local conditions thrombin percutaneous embolization was performed to avoid possible complications of a conventional surgery approach. AVG occlusion was done in 10 min by fluoroscopy and ultrasound guidance. In 24 h the patient was significantly better and after 1 week she had no edema at all. There were no complications and no recanalization was observed after 3 months. Percutaneous thrombin embolization is a safe and effective technique for AVG occlusion in case of intractable arm edema with central vein thrombosis, and most likely to be considered in other situations where arteriovenous graft or fistula ligature is needed.

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.

Clinical outcomes of endovascular therapy with vascular stents for central venous obstruction in hemodialysis patients

BACKGROUND

Symptomatic central venous obstruction (CVO) is sometimes observed in patients undergoing hemodialysis. Angioplasty is generally performed for salvage purposes, and stent implantation is performed as a last resort to prevent permanent venous occlusion. However, published reports about the clinical outcomes of stenting for CVO have been limited by the small number of included patients and the relatively old generation of analyzed stents. This study aimed to clarify the safety and efficacy of endovascular therapy (EVT) using stents for symptomatic CVO in contemporary practice.

METHODS

This retrospective review was performed between May 2012 and August 2021. We retrospectively analyzed consecutive 31 lesions (31 patients, 64 ± 10.7 years old) treated with a vascular stent for elastic recoil after balloon angioplasty or recurrent stenosis <3 months after angioplasty. The primary outcome was primary patency, defined as freedom from target lesion revascularization. The secondary outcome was assisted primary patency, defined as freedom from permanent occlusion of the target stents.

RESULTS

In all cases, stents were successfully deployed on the target lesions. No EVT-related complications were observed. Self-expandable and balloon-expandable stents were used in 26 and 5 lesions, respectively. The median follow-up period was 18 months (interquartile range, 7-40). Kaplan-Meier analysis revealed that the primary patency rates were 66.1 % at 6 months, 61.7 % at 12 months, and 38.4 % at 24 months after EVT. The assisted primary patency rate was 70.3 % 24 months after EVT. In the multivariate analysis, younger age was the only independent predictor of target lesion revascularization (hazard ratio: 0.92, 95 % CI: 0.85-0.99, p = 0.04).

CONCLUSIONS

Stent implantation for CVO that is resistant to standard angioplasty seems safe and effective.

Physician-Modified Fenestrated Endovascular Repair for Iatrogenic Innominate Vein Injury

Iatrogenic innominate vein injuries are rare complications associated with internal jugular venous catheters. These complications are accompanied by high morbidity and mortality rates in patients with severe underlying medical conditions. Without proper treatment, emergency surgery may be needed due to acute cardiac tamponade or hemothorax. Endovascular repair can be advantageous for patients with significant medical comorbidities. Herein, we report the case of a 62-year-old female with an iatrogenic injury to the innominate vein at the subclavian vein and internal jugular confluence due to a malpositioned left internal jugular catheter. A customized fenestrated endograft was positioned with fenestration oriented to the internal jugular vein and a new tunneled catheter was inserted across the fenestration into the superior vena cava upon removal of the malpositioned catheter. In addition, a brachio-basilic arteriovenous fistula was created. At one month follow-up, the patient had a palpable thrill over the arteriovenous fistula and a functioning tunneled catheter.

Clinical Implications of Phenotypes of Hemodialysis Patients With Central Venous Occlusion or Central Venous Stenosis Defined by Cluster Analysis

Objective

This study aims to investigate the association between clinical factors of patients with central (superior vena cava, brachiocephalic, or subclavian) venous occlusion or central venous stenosis (CVO/CVS) and the difficulty of interventional recanalization as well as the duration of postoperative patency.

Methods

A total of 103 hemodialysis patients with CVO/CVS treated with endovascular treatment were enrolled. The two-step cluster analysis was selected to differentiate the cases into distinct phenotypes automatically. Differences in characteristics, the difficulty of interventional recanalization, and the duration of postoperative primary patency time between the two clusters were statistically compared.

Results

The 103 cases were divided into distinct two clusters by the two-step cluster analysis with 48 (46.6%) in cluster 1 and 55 (53.4%) in cluster 2. Compared to cluster 2, patients in cluster 1 have a higher proportion of blunt stump, side branches, occlusion lesions >2 cm, calcification, or organization. Moreover, the above four factors were, in turn, the most critical four predictors distinguishing 103 patients into two clusters. The remaining six factors were, in turn, occlusion located in the superior vena cava (SVC), duration of central venous catheterization (CVC), lesion location, vessel diameter, number of CVC, and previously failed lesion. Of the four most important factors, with the exception of occlusion lesions exceeding 2 cm, there were significant differences in the length of procedure time between the groups grouped by the remaining three factors. And there was a significant difference in the primary patency rate between the group with blunt stump and the group without blunt stump and also between the group with occlusion lesions ≥ 2 cm and the group with occlusion lesions <2 cm. The operation time of cluster 1 was longer than that of cluster 2. In terms of postoperative patency time, the primary patency time was significantly longer in the patients of cluster 2 compared with cluster 1 (P = 0.025).

Conclusion

Patients were divided into distinct two clusters. CVO/CVS of patients in cluster 1 was more challenging to be recanalized than that in cluster 2, and the primary patency time was significantly longer in the patients of cluster 2 compared with cluster 1. Blunt stump, side branches, occlusion lesions exceeding 2 cm, and calcification or organization are the four most critical predictors distinguishing 103 patients into two clusters.

Surgical management of a congenital arteriovenous fistula of the forearm

Congenital arteriovenous fistula (AVF) is a rare vascular disease, which may occur anywhere in the body. The forearm is a very rare location. Clinical manifestations are not very specific and can vary from an asymptomatic fistula to a life-threatening congestive heart failure. Although embolization can be an alternative treatment for AVF of the forearm, surgery is still considered as the standard treatment. Herein, we report the case of a 7-year-old boy with a congenital AVF between the radial artery and the superficial cephalic vein in the forearm without any dysmorphic features treated surgically.

Stent Graft Outcomes in Dialysis Circuits: A Review of Clinical Trials and Literature

End-stage renal disease is a prevalent medical condition causing significant problems as the majority of patients are being treated with dialysis. While dialysis provides a means to compensate for the renal impairment, arteriovenous grafts and fistulas are often complicated by neointimal hyperplasia, loss of primary patency, and graft failure. Over the last decade, stent grafts have emerged as an alternative to balloon angioplasty and bare metal stents for revascularization in the event of arteriovenous graft occlusion or stenosis. Several randomized controlled trials have investigated the efficacy of stent grafts compared with balloon angioplasty for improving the function and durability of dialysis circuits. In this review, we present a comprehensive review of clinical trials. Stent grafts appear to offer increased primary patency over balloon angioplasty in the treatment of dialysis circuit stenosis. However, there is generally no significant difference between the two treatment modalities on other clinically relevant measures like complication rates and overall survival.

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.

Venous stent versus conventional stent for the treatment of central vein obstruction in hemodialysis patients: a retrospective study

BACKGROUND

Endovascular treatment is a first-line treatment for upper thoracic central vein obstruction (CVO). Few studies using bare venous stents (BVS) in CVO have been conducted.

PURPOSE

To evaluate the treatment performance of upper thoracic central vein stenosis between BVS and conventional bare stent (CBS) in hemodialysis patients.

METHODS

Hemodialysis patients with upper thoracic central vein obstruction who underwent endovascular treatment at the interventional unit of our institution from 1 January 2008 to 31 December 2018 were enrolled in the present study. CBS was used to treat central vein obstruction in 43 patients and BVS in 34 patients. We compared the primary patency rates and complications between the two stent types. P values < 0.05 were considered statistically significant.

RESULTS

The patient demographic data between the CBS and BVS groups were similar. The characteristics of the lesions, procedures, and complications were not significantly different between the two groups (P > 0.05). There were no statistically significant differences of primary patency rates at three and six months between the BVS and CBS groups (94.1% vs. 86.0% and 73.5% vs. 58.1%, respectively; P > 0.05). The primary patency rate at 12 months in the BVS group was significantly higher than that in the CBS group (61.8% vs. 32.6%; P = 0.008).

CONCLUSION

Endovascular treatment of central vein obstruction with BVS provided a higher primary patency rate at 12 months than CBS.

Tratamento endovascular de doença oclusiva venosa central com fístula arteriovenosa funcionante

Resumo Contexto A maior sobrevida dos doentes dialíticos somada à incapacidade de obtenção de órgãos suficientes para atender a demanda, bem como à dificuldade de acesso aos serviços de saúde, levou ao aumento da fila para transplante e ao prolongamento do tempo de utilização do acesso venoso central para hemodiálise. A etiologia mais comum de estenose de veia central é o acesso venoso central prolongado, pelas lesões intimais decorrentes da presença do cateter. Objetivos Avaliar resultados de angioplastia para tratamento de doença oclusiva venosa central com fístula arteriovenosa periférica funcionante. Métodos Estudo tipo coorte retrospectivo com revisão de prontuários de 47 doentes com lesões estenóticas ou oclusivas. A avaliação dos doentes foi realizada em 30 dias, 6 meses e 1 ano após a recanalização ou correção da estenose com ATP ou ATP/aplicação de stent. Resultados Lesões estenóticas foram encontradas em 25 doentes (53%), e oclusões, em 22 (47%) doentes. A angioplastia percutânea transluminal (ATP) com stent foi utilizada em 64% dos doentes, e angioplastia isolada com balão, em 36% deles. A análise de resultados clínicos mostrou elevada taxa de melhora clínica precoce (30 dias) em 82% dos doentes (intervalo de confiança [IC] 71-93%). Após 1 ano de seguimento, a taxa de perviedade primária foi de 57%, e a taxa de perviedade primária assistida foi de 72% (IC 57-84%). Conclusão O tratamento endovascular das estenoses ou oclusões de veia central sugere melhora clínica dos sintomas e taxas adequadas de perviedade no período de 1 ano, apesar da limitação no tamanho amostral.

Hemodialysis Reliable Outflow (HeRO) graft creation in upper extremities abandoned due to stent obstruction via recanalization and HeRO outflow component insertion across stent interstices

BACKGROUND

The purpose of this study was to assess the feasibility and outcomes of recanalization and subsequent HeRO graft outflow component insertion across stent interstices in patients with an otherwise abandoned upper extremity.

METHODS

Over a 10-year period, 15 patients underwent central venous recanalization by interventional radiology across the interstices of one or more occluded stents for the purpose of subsequent HeRO graft creation. A tunneled central venous catheter was left across the stent and occlusions with tip in right atrium. On a later date, the catheter was used for rapid guidewire access for HeRO graft implantation in the OR by vascular surgery. Procedural and clinical outcomes were determined by retrospective review. Primary and secondary HeRO graft patency rates were estimated with the Kaplan-Meier technique.

RESULTS

The technical success rates of recanalization across stent interstices was 100% (15/15). Between one and four overlapping stent walls were traversed. The technical success of the patients who underwent attempted HeRO graft implantation with outflow component traversing across stent interstices was 91% (11/12). No major complications were encountered with either recanalization or HeRO graft implantation. The primary and secondary HeRO patency rates at 12 months were 64% and 80%, respectively.

CONCLUSION

HeRO graft insertion across stent interstices is feasible and can provide effective permanent AV access; thus, the presence of stents across the subclavian and brachiocephalic veins should not be considered a contraindication.

Percutaneous Transluminal Angioplasty in Chronic Total Subclavian Venous Stenosis Using Coronary Guidewire: A Case Report

Arteriovenous fistula is the best permanent vascular access for hemodialysis (HD). However, in our country, HD catheter in jugular or subclavian vein is more commonly found because our patients prefer to hold HD until the complications are unbearable. The catheter increases risk of venous stenosis on site and in surrounding vessels, resulting in access loss. Percutaneous transluminal angioplasty (PTA), combined with stent deployment, can be utilized as main treatment for such stenosis in subclavian vein. This method dated back to two decades ago with high success rate. Nevertheless, reports or studies of angioplasty in total occlusion are scarce, mainly because of lower success rate and the need of smaller penetrating wire. We describe our experience in performing PTA and stent deployment using coronary wire to penetrate total occlusion in subclavian venous stenosis after vein cannulation. We hope that we can give an alternative technique to avoid surgery in such cases.

Non-conventional vascular accesses for the management of superior vena cava syndrome in patients with Intestinal Failure. Case series and systematic review

BACKGROUND

Type III Intestinal Failure (IF) is a devastating clinical condition.characterized by the inability of the gut to absorb necessary macronutrients, and/or water and electrolytes, requiring Parenteral Nutrition (PN) as chronic therapy. Long-term PN may lead to life-threatening complications; the loss of central venous access (LCVA) is the most frequent and challenging. To date, few studies in the literature have reported the relevance of Non-conventional Vascular Accesses (NCVA) in the management IF as part of the comprehensive multidisciplinary care.

METHODS

A retrospective analysis of a database collected from January 2006 to December 2019 was performed using SPSS v25.0 for statistical analysis, followed by a systematic review, using the PRISMA.methodology RESULTS: From January 2006 to December 2019, 184 NCVA were placed in 71 patients with LCVA as IF-related complication; 173 were placed in 61 patients by interventional radiology (IR) and 11 NCVA were placed in 10 patients by the surgical team during the intestinal transplant (ITx) operation. From the 173 IR procedures 166 (95.9%) were successful with 3 ± 2.7 procedures/patient; average catheter permanence rate was 738.68 ± 997 days; complications related to the procedures occurred in 18/173 (10.4%), including two deaths. On the other hand, among the 11 NCVA implanted by the surgical team, 7 (64%) were successful and were safely withdrawn 30 days after ITx when were no longer needed; 2 (18%) catheters malfunctioned during the first week and could not be further used, and 1 was accidently removed; average catheter permanence rate was 26 ± 4 days. There was one complication (9%) requiring laparotomy; there was no mortality associated the procedure in this group. A systematic review was conducted to evaluate the success and safety of NCVA as part of the treatment of HPN-related complications; from 337,542 papers, 14 studies were included. A total of 28 HPN-patients with LCVA received NCVA; 34 procedures were successfully performed, while procedure-related complications were reported in 11.7%, as well as one death.

CONCLUSIONS

The data analyzed show that NCVAs may be successfully placed by expert teams, allowing to sustain long-term PN, as well as increasing the Intestinal Transplantation applicability for candidates in the extreme need of vascular access.

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 retrospective cohort study comparing high and low balloon inflation pressure on technical success and patency for treating central venous lesions in patients on chronic hemodialysis

Background

We aimed to analyze the success rates and the access patency rates at 12 months between patients on chronic hemodialysis with symptomatic central venous stenosis (CVS) or occlusion (CVO), receiving high or low balloon inflation pressure for treatment.

Methods

We performed a retrospective study in which angioplasty balloons were inflated using a low-pressure or a high-pressure for the management of hemodialysis patients with CVS/CVO. The outcomes of this study were the success rate and the access patency rates at 12 months after balloon angioplasty, and the differences between groups were compared.

Results

We included a total of 74 patients on hemodialysis and assigned them to the low-pressure or the high-pressure groups. Success rates in patients of the high-pressure group (94.12%) were higher than those in patients of the low-pressure group (67.50%) (p = 0.005). With a total of 59 patients with technical success, at 6 and 12 months after angioplasty, the rates of access patency in the low-pressure group were 68 and 48%, respectively; on the other hand, the primary patency rates in the high-pressure group were 86.67% (6-months) and 76.67% (12-months). The 6 and 12 months post-interventional patency rates were higher in patients of the high-pressure group than those in patients of the low-pressure group (p = 0.10 at 6 months and p = 0.03 at 12 months).

Conclusions

Compared to balloon angioplasty using a low inflation pressure, hemodialysis patients with CVS/CVO receiving angioplasty using a high inflation pressure have significantly higher technical success and 12-month patency rates.

Unilateral jugular vein stenosis in five horses and experience with percutaneous transluminal angioplasty

BACKGROUND

Venous stenosis, a possible cause of jugular dilatation and congestion, is well known in human medicine but has poorly been described in horses.

OBJECTIVE

To report unilateral jugular vein stenosis as a cause of jugular vein dilatation in horses and describe treatment by percutaneous transluminal angioplasty (PTA).

STUDY DESIGN

Case report.

METHODS

Details of horses diagnosed with unilateral jugular stenosis were retrieved from medical records.

RESULTS

Five horses were presented with a non-painful, unilateral dilatation of the jugular vein of which two horses showed headshaking during exercise. In one horse an indwelling catheter had been used and jugular dilatation developed 4 weeks later. In the other horses, no intravenous injections had been administered in the months before jugular dilatation developed. Ultrasonographic examination revealed venous stenosis in all horses approximately 5-10 cm cranial to the thoracic inlet. The internal diameter at the level of this stenosis was only 1-3.1 mm. The length of the stenosis was about 15-19 mm with a markedly thickened intima and media on ultrasonography. After enoxaparin treatment, PTA was performed in three horses. During the procedure the stenotic vein was dilated three times with progressively increasing pressures up to 12 atm. The stenotic diameter increased to a maximum of 4.9 mm with improved jugular blood flow. Aftercare included anti-inflammatory and anti-thrombotic therapy.

CONCLUSION

Jugular vein stenosis occurs in horses and should be included in the differential diagnoses of unilateral jugular vein dilatation. It may present in the absence of previous intravenous treatment. PTA of the jugular vein is feasible to improve jugular blood flow.

Gianturco Z-stent placement for the treatment of chronic central venous occlusive disease: implantation of 208 stents in 137 symptomatic patients

PURPOSE

To report the technical successes, adverse events, and long-term stent patency rates of Gianturco Z-stents for management of chronic central venous occlusive disease.

METHODS

Overall, 137 patients, with mean age 48.6±16.1 years (range, 16-89 years), underwent placement of Gianturco Z-stents for chronic central venous occlusions. Presenting symptoms included lower extremity edema (n=66, 48.2%), superior vena cava syndrome (n=30, 21.9%), unilateral upper extremity swelling (n=20, 14.6%), hemodialysis fistula or catheter dysfunction (n=11, 8.0%), ascites (n=8, 5.8%), and both ascites and lower extremity edema (n=2, 1.5%). Most common etiologies of central venous occlusion were prior central venous access placement (n=58, 42.3%), extrinsic compression (n=29, 21.2%), and post-surgical anastomotic stenosis (n=27, 19.7%). Number of stents placed, stent implantation location, stent sizes, technical successes, adverse events, need for re-intervention, follow-up evaluation, stent patencies, and mortality were recorded. Technical success was defined as recanalization and stent reconstruction with restoration of in-line venous flow. Adverse events were defined by the Society of Interventional Radiology Adverse Event Classification criteria. Primary and primary-assisted stent patencies were analyzed using Kaplan-Meier analysis.

RESULTS

In total, 208 Z-stents were placed. The three most common placement sites were the inferior vena cava (n=124, 59.6%), superior vena cava (n=44, 21.2%), and brachiocephalic veins (n=27, 13.0%). Technical success was achieved in 133 patients (97.1%). There were two (1.5%) severe adverse events (two cases of stent migration to the right atrium), one (0.7%) moderate adverse event, and one (0.7%) mild adverse event. Mean follow-up was 43.6±52.7 months. Estimated 1-, 3-, and 5-year primary stent patency was 84.2%, 84.2%, and 82.1%, respectively. Estimated 1-, 3-, and 5-year primary-assisted patency was 92.3%, 89.6%, and 89.6%, respectively. The 30- and 60- day mortality rates were 2.9% (n=4) and 5.1% (n=7), none of which were directly attributable to Z-stent placement.

CONCLUSION

Gianturco Z-stent placement is safe and effective for the treatment for chronic central venous occlusive disease with durable short- and long-term patencies.

Access flow volume (Qa) and survival in a hemodialysis population: An analysis of 5208 Qa measurements over a 9-year period

BACKGROUND

Aim of the study was to determine associations between characteristics of arteriovenous access (AVA) access flow volume (Qa, mL/min) and four year freedom from cardiovascular mortality (4yr-CVM) in hemodialysis (HD) patients.

METHODS

HD patients who received a primary AVA between January 2010 and December 2017 in one center were analyzed. Initial Qa was defined as the first Qa value obtained in a well-functioning AVA by a two-needle dilution technique. Actual Qa was defined as access flow at a random point of time. Changes in actual Qa were expressed per 3-month periods. CVM was assessed according to the ERA-EDTA classification. The optimal cut-off point for initial Qa was identified by a receiver operating characteristic curve. A joint modelling statistical technique determined longitudinal associations between Qa characteristics and 4yr-CVM.

RESULTS

A total of 5208 Qa measurements (165 patients, male n = 103; age 70±12 years, autologous AVA n = 146, graft n = 19) were analyzed. During follow-up (Dec 2010-Jan 2018, median 36 months), 79 patients (48%) died. An initial Qa < 900 mL/min was associated with an increased 4y-CVM risk (HR: 4.05; 95% CI [1.94-8.43], P<0.001). After 4 years, freedom from CVM was 34% lower in patients with a Qa < 900 mL/min (53 ±7% vs. Qa ≥ 900 mL/min: 87 ±4%, P <0.001). An association between increases in actual Qa over 3-month periods and mortality was found (HR: 4.48 per 100mL/min, 95% CI [1.44-13.97], P =0.010) indicating that patients demonstrating increasing Qa were more likely to die. By contrast, actual Qa per se was not related to survival.

CONCLUSIONS

Studying novel arteriovenous access Qa characteristics may contribute to understanding excess CVM in HD patients.

Left innominate vein stenosis treated with graft replacement with concomitant cardiac surgery

Left innominate vein stenosis is a serious complication that causes massive venous hypertension and vascular access failure in patients requiring hemodialysis. Percutaneous transluminal angioplasty has been the standard treatment strategy; however, the outcome has been unsatisfactory, with a low primary patency rate. We present the case of a 49-year-old man with symptomatic left innominate vein stenosis that was successfully treated with graft replacement concomitantly with aortic valve replacement via median sternotomy. During surgery, appropriate cardiopulmonary bypass circulation should be established to avoid cerebral venous hypertension, which can cause irreversible brain damage.

Use of a VBX balloon expandable stent-graft for management of right brachiocephalic vein stenosis

Here we describe the use of a VBX balloon expandable stent-graft (WL Gore, Flagstaff, AZ, USA) to treat a right brachiocephalic vein stenosis in a haemodialysis patient prior to ipsilateral upper limb arterio-venous (AV) fistula formation. Balloon expandable stent-grafts are unsuitable for treating peripheral fistula stenoses due to their susceptibility of being crushed. The right brachiocephalic vein is both relatively short in comparison to the left and is less susceptible to extrinsic compression and the use of such a device to treat stenosis here allows for very accurate placement and restoration of luminal diameter. The advantages and disadvantages of using these devices in haemodialysis access circuits are also discussed herein, in what we believe to be the first report of the application of a dedicated commercially available balloon expandable stent graft in a haemodialysis patient.

Thoracic outlet decompression for subclavian venous stenosis after ipsilateral hemodialysis access creation

OBJECTIVE

Central venous stenosis is one of the most challenging complications in patients requiring hemodialysis. Venous thoracic outlet syndrome is an underappreciated cause of central venous stenosis in patients requiring dialysis that can result in failed percutaneous intervention and loss of a functioning dialysis access. Limited data exist about the safety and outcomes of first rib resection in patients requiring hemodialysis, and the results have been confounded by the various surgical approaches used. The purpose of the present study was to evaluate the safety, operative outcomes, and patency of the existing dialysis access after transaxillary thoracic outlet decompression.

METHODS

A retrospective medical record review was performed from January 2008 to December 2019 of patients who had undergone thoracic outlet decompression for subclavian vein stenosis with ipsilateral upper extremity hemodialysis access. The baseline characteristics and comorbidities were reviewed. The operative and postoperative course were evaluated. The survival and patency rates were analyzed using the life-table method and Kaplan-Meier curve.

RESULTS

A total of 18 extremities in 18 patients were identified. Their mean age was 59 ± 11 years, and 89% were men. A total of 13 fistulas and 5 grafts were included. All patients had undergone repair via a transaxillary approach. First rib resection, anterior scalenectomy, and circumferential venolysis were performed in all 18 patients. The mean operative time was 99 ± 19 minutes, with an estimated blood loss of 78 ± 66 mL. The median length of stay was 2 days. No patient had died at 30 days. The survival rate at 1 year was 83%. The primary, primary-assisted, and secondary patency at 1 year were 42%, 69%, and 93%, respectively.

CONCLUSION

Thoracic outlet decompression via the transaxillary approach is a technically feasible and safe operation in patients with ipsilateral upper extremity hemodialysis access. Patients with threatened dialysis access due to subclavian vein stenosis should be carefully evaluated for possible extrinsic compression at the costoclavicular junction. These patients might benefit from transaxillary first rib resection, scalenectomy, and venolysis.

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.

Endovascular mechanical thrombectomy and stenting in a case of central vein thrombosis

Central vein stenosis and thrombosis are frequent in patients on haemodialysis for end-stage renal disease. Its management includes anticoagulation, systemic or catheter-directed thrombolysis, mechanical thrombectomy and percutaneous transluminal angioplasty (PTA). Use of mechanical thrombectomy in central vein thrombosis has been scarcely reported. We hereby report a case of right brachiocephalic vein thrombosis with underlying stenosis, which was successfully treated by mechanical thrombectomy followed by PTA and stenting. The patient had a favourable 10 months of follow-up.

Outcome of stenting in central venous obstruction of benign etiology

Background: The aim of this study is to evaluate long term outcome in patients treated for benign superior vena cava (SVC) syndrome by endovascular techniques. Patients and methods: Between 2015 and 2018, 62 patients suffering from central venous obstruction of benign etiology underwent balloon angioplasty with stent placement for venous obstruction in our department. Patency was assessed clinically, using duplex ultrasound in all patients or with CT-phlebography in selected cases. Results: Median age was 60 years (23-83), forty-one patients (66%) had central venous devices. Swelling of the arm and face were the main symptoms (71%). During the median follow up of 22 months (9-38), cumulative primary patency was 71% after venous stenting. The cumulative assisted primary and the secondary patency were 85% and 92%, respectively. Conclusions: Recanalization and stenting of central vein obstruction has turned out to be the technique of reference and provides satisfactory mid-term patency rates. After adjusting for the risk factors, presence of AV-fistula remained a significant risk factor for recurrent stenosis or loss of patency after intervention.

Endovascular treatments of tunneled central venous catheter-induced superior vena cava complete occlusion via through-and-through technique

BACKGROUND

Superior vena cava occlusion (SVCO) induced by tunneled central venous catheter (tCVC) is an uncommon but challenging complication of hemodialysis patients. The aim of this study was to access the efficacy, safety, and patency of stents in tCVC-related SVCO via through-and-through technique.

METHOD

We retrospectively identified seven patients with benign SVCO secondary to tCVC treated with endovascular approaches successfully between 1 March 2013 and 31 October 2019. Patients' demographic data, clinical signs and symptoms, and imaging data were followed up and recorded.

RESULTS

Technical success was achieved in all cases. All the patients were performed with percutaneous transcatheter angioplasty (PTA) and subsequently stent placement via the through-and-through technique. During follow-up, four patients underwent secondary interventions, including PTA and/or stent placement. The primary patency after 3, 6, 9 and 12 months was 100%, 100%, 86% and 86%, and secondary patency after 12 months was 100%. No procedure-related deaths occurred.

CONCLUSIONS

Endovascular management of SVCO is a safe and effective approach. CT examination can provide a direction for endovascular treatment and periodic surveillance.

Results of Stenting for Central Venous Occlusions and Stenoses in the Hemodialysis Patients

Objectives: We aim to investigate the results of stenting for central venous occlusions and stenoses in the hemodialysis patients.

Methods: Twenty-nine cases treated with endovascular recanalization with deployment of bare metal stent (BMS) for central venous occlusions (24 cases) and recurrent stenoses (5 cases) between 2014 and 2018 were retrospectively analyzed. Results of these procedures including success rate, operative time, estimated blood loss, morbidity, primary patency, assisted primary patency and freedom from target-lesion revascularization (TLR) were evaluated.

Results: Nine lesions were in brachiocephalic vein (Occlusion/Stenosis: 8/1) and 20 lesions were in subclavian vein (Occlusion/Stenosis: 16/4). Procedural success was 94% (29/31 cases) and operation time/estimated blood loss was 68±39 min/28±54 g. Symptom were relieved or disappeared in all successful cases. Morbidity (extravasation of contrast medium) was 3% (1/29). During the period of observation, 1 stent fracture with occlusion and 1 stent migration to periphery were recognized. 1-year primary patency, freedom from TLR, and assisted primary patency were 40% (median patent time: 256 days), 67% (median patent time: 524 days), and 77%, respectively.

Conclusion: Stenting for central venous occlusions and stenoses in the hemodialysis patients is safe and durable treatment option. However, considering its off-label use and potential hazard including vessel rupture, stent migration, and stent fracture, the indication for BMS deployment should be conservative, and interventionist should be well acquainted with prevention and measures to these complications. (This is a translation of Jpn J Vasc Surg 2019; 28: 193–198.)

Evaluating a Novel Telescoping Catheter Set for Treatment of Central Venous Occlusions

BACKGROUND

Central venous occlusive disease (CVOD) is a prevalent problem in patients with end-stage renal disease (ESRD) and can lead to access malfunction or ligation for symptomatic relief. The purpose of this study is to evaluate the efficacy of the TriForce® Peripheral Crossing Set (Cook Medical), a novel reinforced telescoping catheter set designed to provide additional support for crossing difficult central venous occlusions.

METHODS

This is a single-center retrospective study from a quaternary referral center. We identified 37 patients over a 17-month period who underwent 56 attempts at endovascular recanalization for the treatment of central venous occlusion. Technical success rates, procedural data, and outcomes were compared between those undergoing recanalization using traditional wire/catheter sets versus the TriForce catheter set.

RESULTS

Average age was 48 ± 2 years. Comorbidities were similar between the two cohorts and included ESRD (61%), deep venous thrombosis (30%), and May-Thurner syndrome (7%). Forty attempts were made with traditional wire/catheter sets and 16 attempts with the TriForce catheter set to treat 2.1 ± 0.2 and 1.9 ± 0.3 occluded venous segments, respectively (P = 0.74). Technical success rates were significantly higher for the group undergoing recanalization using the TriForce catheter (69% versus 38%, P = 0.04) and 4 patients were successfully recanalized using the TriForce catheter set after a failed attempt with traditional wire/catheter sets. Mean fluoroscopy time and radiation dose were 13 ± 3 min and 14,623 ± 2,775 μGy∗m² for traditional techniques versus 30 ± 6 min and 30,408 ± 10,433 μGy∗m² for the novel telescoping catheter set (P = 0.01 and 0.09, respectively). Freedom from reintervention at 1 year was 60% for the TriForce cohort versus 44% for the traditional wire/catheter cohort (P = 0.25).

CONCLUSIONS

The novel TriForce reinforced telescoping catheter set is a useful adjunct that may improve recanalization rates of CVOD compared with traditional wire/catheter sets.

Efficacy of stent-graft placement to salvage central vein stents with recalcitrant restenosis in patients with arteriovenous fistulas

The purpose of this study was to determine the effectiveness and permanency of stent-graft placement to salvage stents with recalcitrant restenosis due to central vein stenosis (CVS). Between May 2014 and February 2016, VIABAHN stent-grafts were deployed in patients with functioning arteriovenous (AV) fistulas who underwent previous bare metal stent (BMS) placement and had recalcitrant stent restenosis that did not respond to percutaneous transluminal angioplasty (PTA). Surveillance was carried out at 3, 6, 12, 18, and 24 months with diagnostic fistulography. Fourteen patients initially underwent 15 BMS placements. In the follow-up period (range, 118-976 days), patients presented with symptomatic venous hypertension; subsequently, a total of 52 unsuccessful repeat PTAs for BMS restenosis were undertaken, and the median primary access survival of PTAs was 66 ± 43 days. For salvage, 14 stent-grafts were placed in segments with recalcitrant restenosis of a CVS stent. Within 1.25 ± 0.72 days after stent-graft placement, patients who initially presented with symptomatic venous hypertension reported complete resolution. The median primary access survival (mean, 1183 ± 312 days) was longer than PTAs alone (P < .01). No major or minor complications were associated with stent-graft deployment or any of the subsequent interventions in the study period. The primary patency rate at 6, 12, and 18 months was 100%, and it was 85.7% at 24 months. The secondary access patency rate was 92.9% at 24 months. In conclusion, stent-graft placement to salvage CVS stents with recalcitrant restenosis in patients with AV fistulas is safe and effective if PTAs fails to maintain luminal patency.

Outcome of Central Vein Occlusion Recanalization in Hemodialysis Patients and Predictors for Success: A Retrospective Study

Background:

Catheter-directed treatment is the standard approach for the management of chronic central venous occlusion.

Purpose:

The objective of this study is to report the outcome of conventional recanalization of chronic central vein occlusion in hemodialysis patients and to determine the predictors for success.

Material and Methods:

All hemodialysis patients who underwent endovascular recanalization of central vein occlusion from January 2012 to December 2016 were retrospectively evaluated. The procedure was percutaneous transluminal angioplasty. Stenting was performed in case of a significant recoil stenosis. Kaplan-Meier analysis was used to evaluate central vein patency. Univariate analysis and multivariate logistic regression were used to calculate the predictive factors.

Results:

Ninety-seven patients (mean age, 61.2 years; range, 25‒89 years old) with 97 central vein occlusions were enrolled. Technical success was achieved in 49 patients (50.5%). The primary patency rates of central veins at 6 and 12 months were achieved in 17 patients (34.4%) and 8 patients (15.8%), respectively. The assisted primary patency rates at 6 and 12 months were achieved in 38 patients (77.3%) and 30 patients (61%), respectively. Patient age ≥60 years and a tapered-type of lesion were significant predictive factors for successful recanalization.

Conclusion:

Endovascular treatment of the central vein occlusion using a conventional technique is moderately effective and safe. Angioplasty alone and stenting were not significantly different in terms of patency rate. The age of the patients and type of occlusion were significant predictors for successful recanalization.

KDOQI Clinical Practice Guideline for Vascular Access: 2019 Update

The National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (KDOQI) has provided evidence-based guidelines for hemodialysis vascular access since 1996. Since the last update in 2006, there has been a great accumulation of new evidence and sophistication in the guidelines process. The 2019 update to the KDOQI Clinical Practice Guideline for Vascular Access is a comprehensive document intended to assist multidisciplinary practitioners care for chronic kidney disease patients and their vascular access. New topics include the end-stage kidney disease "Life-Plan" and related concepts, guidance on vascular access choice, new targets for arteriovenous access (fistulas and grafts) and central venous catheters, management of specific complications, and renewed approaches to some older topics. Appraisal of the quality of the evidence was independently conducted by using a Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach, and interpretation and application followed the GRADE Evidence to Decision frameworks. As applicable, each guideline statement is accompanied by rationale/background information, a detailed justification, monitoring and evaluation guidance, implementation considerations, special discussions, and recommendations for future research.

[Thoracic Central Venous Occlusive Disease and Haemodialysis Access]

Benign central venous thoracic occlusion is a frequent issue in haemodialysis patients. Symptomatic stenosis affects quality of life and can cause dysfunction of arteriovenous access or make it impossible to implant a haemodialysis catheter. Common risk factors for the development of the occlusions are central venous catheters and cardiac rhythm devices. The gold standard for diagnosis is venous angiography. Treatment of asymptomatic lesions can lead to clinical deterioration and should be avoided. The primary method of treatment for symptomatic patients is endovascular therapy. Repeat balloon angioplasty is a standard therapy. In case of elastic recoiling or early recurrence, placement of bare metal stent or stent graft could be considered. Surgical options should be preserved only for refractory cases. Further randomised trials are needed to prove the efficacy of new devices, such as dedicated venous stents and drug coated balloons.

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.

Inferior Vena Cava Reconstruction in Symptomatic Patients Using Palmaz Stents: A Retrospective Single-Center Experience

BACKGROUND

The use of stents for treating central venous occlusion is well described. Limited evidence exists related to Palmaz balloon-expandable stent use in inferior vena cava (IVC) reconstruction. We analyzed patency and complication rates after IVC reconstruction using Palmaz stents.

METHODS

From 2002 to 2019, 37 patients (mean age: 51 year) underwent IVC reconstruction with 68 Palmaz stents. Indications were symptomatic chronic venous obstruction in the infrarenal (n = 25) and intrahepatic (n = 12) IVC. Demographic, operative, and imaging data were evaluated. Clinical data, abdominal CT, and/or duplex ultrasound were used to determine patency at follow-up.

RESULTS

Restoration of caval patency was achieved in all patients, with complications in 2/37 (5.4%) patients (thrombus formation within the stent; stent embolization eight days after placement). Follow-up data were available for 27 patients. Primary patency was maintained through last follow-up in 19/27 (70%) patients (mean: 1.1 year), with successful stent redilation performed in 6 patients. Mean duration of primary-assisted patency (n = 5) was 1.2 year. Late lumen loss was (n = 13) was 40% during a mean time to follow-up of 2.0 years. Primary patency in patients with occlusion secondary to malignancy was 109 day (range: 1 day-1.0 year), whereas primary patency in patients with occlusion from other etiologies was 1.1 year (range: 2 day-5.9 year). The Kaplan-Meier analysis demonstrated primary and primary-assisted patency of 66% and 84%, respectively, at 24 and 48 months.

CONCLUSIONS

Palmaz balloon-expandable stents for IVC reconstruction is feasible and effective for symptomatic IVC occlusion. Risk of stent migration was low.

Analysis of the positional relationship between the left brachiocephalic vein and its surrounding vessels via computed tomography scan: A retrospective study

OBJECTIVES

This study aimed to clarify the positional relationship between the left brachiocephalic vein and its surrounding vessels and to analyse the association between this positional relationship and ageing.

METHOD

Chest contrast-enhanced computed tomography was performed for 100 adults. The contact number between left brachiocephalic vein and surrounding vessels (aorta, brachiocephalic artery, left common carotid artery and left subclavian artery) was determined. The correlations of ageing with the cross-sectional areas of left brachiocephalic vein crossing brachiocephalic artery and left common carotid artery and peripheral end of left brachiocephalic vein were analysed.

RESULTS

LBV was in contact with aorta in 19, brachiocephalic artery in 97, left common carotid artery in 90 and left subclavian artery in 21 patients. There were significant negative correlations of ageing with the cross-sectional areas of left brachiocephalic vein crossing brachiocephalic artery and left common carotid artery and peripheral end of left brachiocephalic vein.

CONCLUSIONS

Brachiocephalic artery and left common carotid artery have easy contact with left brachiocephalic vein. There was a negative relationship between the cross-sectional area of left brachiocephalic vein and age.

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.