Central Venous Obstruction Research Articles

CT guided sharp recanalization to restore dialysis access in patients with central venous obstruction: A single centre experience and review of alternative techniques.

Central venous obstructions that impedes catheter placement or results in catheter dysfunction is a significant problem for haemodialysis patients. Recanalization can be performed with an intent to restore central venous access, improve outflow from arteriovenous fistula or to relieve symptomatic venous obstructions. Sharp recanalization encompasses various interventional techniques using a sharp instrument to puncture through or bypass around a venous obstruction. In this paper we outline our experience performing CT guided sharp recanalization and review alternative sharp recanalization techniques that are specifically used to restore haemodialysis access in patients with thoracic central venous obstruction.

Intravertebral collateral enhancement resembling sclerotic metastatic disease in a case of cervical epidural abscess.

Vertebral body enhancement is occasionally seen on postcontrast CT imaging in the absence of osseous pathology. This enhancement can mimic sclerotic osseous metastatic disease, leading to a diagnostic dilemma for radiologists and increasing the chance of misinterpretation. Existing literature has focused on the association between this enhancement and concomitant central venous system obstruction. We report a 61-year-old woman with a history of nasopharyngeal carcinoma presenting with an epidural abscess who exhibited vertebral body enhancement resembling sclerotic metastatic disease without imaging evidence of central venous obstruction or vertebral osseous metastatic disease. Awareness of this unique presentation may prevent the incorrect diagnostic errors and their associated negative effects on patients.

Clinical outcomes and predictive factors of stent grafts treatment for symptomatic central venous obstruction in end stage kidney disease patients with arteriovenous access

To assess the efficacy of stent grafts (SGs) in managing central venous obstruction disease (CVOD) in hemodialysis (HD) patients with arteriovenous (AV) access, and to identify predictive factors influencing the SG treatment outcomes. HD subjects with CVOD who underwent SGs placement at our center between August 2018 and June 2022 were enrolled. Survival curve analysis using the Kaplan–Meier method and log-rank test was performed. Cox proportional hazards regression analysis was employed to identify predictive factors associated with outcomes. A total of 59 SG implantation procedures for CVOD were analyzed, comprising 30 cases of stenosis and 29 cases of occlusion. The access circuit primary patency (ACPP) at 6, 12, and 24 months post-SG placement were 80.9%, 53.8%, and 31.4%, respectively, while, the target lesion primary patency (TLPP) were 91.3%, 67.6%, and 44.5%, respectively. Subgroup analysis revealed higher TLPP in the stenosis group compared to the occlusion group, although the difference was not statistically significant (P = 0.165). The TLPP was significantly improved by SG placement in those who had antecedent balloon dilations (P < 0.001). Cox proportional hazards regression identified target lesion length ≥ 30 mm and procedure defects as independent predictors of lower TLPP after SG treatment for CVOD in HD patients. SG placement demonstrates safety and efficacy in managing CVOD among HD patients, leading to improved TLPP of endovascular therapy (EVT) for CVOD. Notably, long target lesions (≥ 30 mm) and procedure defects emerged as predictive factors influencing TLPP.

Diagnostic Value of Contrast-Enhanced Ultrasonography for Catheter-Related Right Brachiocephalic Vein and Superior Vena Cava Lesions in Patients Undergoing Hemodialysis-A Pilot Study.

To evaluate the diagnostic efficacy of contrast-enhanced ultrasonography (CEUS) for detecting catheter-related right brachiocephalic vein (RBV) and superior vena cava (SVC) obstructions in patients undergoing hemodialysis (HD). From June 1, 2021 to December 31, 2022, we enrolled 80 patients undergoing HD who had used or were using a central venous catheter as vascular access. We evaluated the diagnostic efficacy of conventional ultrasonography and CEUS for identifying RBV and SVC obstructions and compared them with that of digital subtraction angiography (DSA). In the stratified analysis, the SVC was divided into the upper and lower segments. In total, we analyzed 240 central venous segments, including the RBV. Among the RBV and SVC visualized by DSA, conventional ultrasonography and CEUS could visualize 67.92 and 100% of the vein segments, respectively; however, the lengths and diameters of the RBV and SVC were smaller than those recorded with DSA (P < .001). The diagnostic efficacy of CEUS for detecting catheter-related central venous obstruction was better than that of conventional ultrasonography, with a higher sensitivity (83.95 vs 41.98%), specificity (89.94 vs 53.46%), accuracy (87.92 vs 49.58%), and F1 score (82.42 vs 49.64%). CEUS showed good agreement (κ = 0.732) with DSA. In the stratified analyses, CEUS also showed higher sensitivity (83.93, 83.33, and 84.62%, respectively) and better agreement with DSA (κ = 0.635, 0.655, and 0.673, respectively) than conventional ultrasonography for detecting the RBV and the upper and lower segments of the SVC. CEUS had high sensitivity and specificity in diagnosing catheter-related RBV and SVC obstructions.

Sewing a Silk Purse from a Sow’s Ear: Performance Goals for Thoracic Central Vein Obstruction

Objective Performance Goals Based on a Systematic Review and Meta-Analysis of Outcomes for Bare Metal Stents and Angioplasty for Hemodialysis-related Central Venous ObstructionJournal of Vascular and Interventional RadiologyPreviewTo use safety and efficacy outcomes following treatment with percutaneous transluminal angioplasty (PTA) and/or stent placement for thoracic central venous obstruction (TCVO) in hemodialysis-dependent patients to establish objective performance goals (OPGs). Full-Text PDF

Additive Therapy of Plasmodium berghei-Induced Experimental Cerebral Malaria via Dihydroartemisinin Combined with Rapamycin and Atorvastatin.

Cerebral malaria (CM), caused by Plasmodium falciparum, is the primary cause of death from severe malaria. Even after immediate parenteral therapy with antimalarial drugs, the mortality rate remains 15 to 25%. Currently, no effective therapeutic agents are available for the radical treatment of CM. Thus, further in-depth explorations of adjuvant therapies in combination with antimalarial drugs are urgently needed. The experimental cerebral malaria (ECM) model was established by infecting C57BL/6 mice with Plasmodium berghei ANKA. Subsequently, infected mice were continuously treated with dihydroartemisinin (DHA) in combination with rapamycin (RAP) and atorvastatin (AVA) for 5 days at different time points, including day 0, day 3, and day 6 postinfection (p.i.). Treatment efficacy was evaluated by comparing behavioral scores, body weight, parasitemia, survival rate, blood-brain barrier (BBB) integrity, and histopathology. The optimal combination therapy of DHA, RAP, and AVA on day 3 p.i. was selected for ECM. This strategy significantly improved survival rate, reduced parasitemia, improved the rapid murine coma and behavioral scale scores and permeability of the BBB, attenuated cerebrovascular and hepatic central venous obstruction and hemozoin deposition in the liver, and decreased the red pulp area of the spleen, which effectively ameliorated neurological damage in ECM. It also improved histopathology and neurological damage caused by ECM. In this study, the optimal therapeutic strategy for ECM was selected, which is expected to be a potential therapy for human CM. IMPORTANCE Although artemisinin-based combination therapies (ACTs) have greatly improved the clinical outcome of cerebral malaria (CM) as a fatal disease that can permanently disable a significant proportion of children even if they survive, new treatment options are needed as Plasmodium falciparum develops resistance to antimalarial drugs. Recent reports suggest that basal treatment with artemisinin derivatives often fails to protect against cell death, neurological damage, and cognitive deficits. In this study, the combination of dihydroartemisinin with rapamycin and atorvastatin improved the current antimalarial outcomes by overcoming the limitations of current antimalarials for CM morbidity and neurological sequelae. This combination offers a new adjunctive treatment for the clinical treatment of human CM in susceptible populations, including children under 5 years old and pregnant women.

Efficacy of Balloon Angioplasty in Patients with Central Venous Stenosis or Obstruction Resulting from Central Vein Catheter Placement

Efficacy of Balloon Angioplasty in Patients with Central Venous Stenosis or Obstruction Resulting from Central Vein Catheter Placement

EFFECTIVENESS OF ASCORBIC ACID AND SALINE SOLUTION IN PEDIATRIC CENTRAL VENOUS ACCESS: RANDOMIZED CLINICAL TRIAL

Objective: to compare the effectiveness between the use of ascorbic acid and 0.9% saline solution in the prevention of pediatric central venous catheter obstruction. Method: randomized clinical trial conducted in a public hospital in Paraná, between the months of June 2018 to October 2019 with 152 participants, of which, 73 in the experimental group and 79, control group) who underwent central venous catheter insertion and randomized to receive the flush intervention with ascorbic acid or 0.9% saline solution. Results: Catheter obstruction occurred in 17 cases (11.2%), nine (11.4%) in the control group and eight (10.9%) in the experimental group. Thrombotic obstruction occurred in 15 cases, in a similar way, in both groups (p=0.88). Catheter removal occurred in 82 cases for elective reasons and in 63 cases for complications. Conclusion: the use of ascorbic acid is as efficient as 0.9% saline solution in preventing central venous catheter obstruction. The study expands the possibilities of interventions within the theme.

Routine use of concurrent fluoroscopic imaging during superficial endovenous interventions: A position statement of the International Union of Phlebology, the Australasian College of Phlebology, the Australia and New Zealand Society for Vascular Surgery, the American Venous Forum, the American Vein and Lymphatic Society, the European College of Phlebology and the Interventional Radiology Society of Australasia.

International evidence-based guidelines recommend preoperative duplex ultrasound mapping in the assessment of chronic venous disease, and concurrent ultrasound imaging to guide superficial endovenous interventions such as endovenous laser ablation, radiofrequency ablation, cyanoacrylate adhesive closure, and sclerotherapy (ultrasound-guided sclerotherapy). Other imaging modalities such as venography, alone or in combination with computed tomography scan or magnetic resonance imaging, may be included in the preoperative assessment of a small and select group of patients to exclude central venous obstruction, certain deep venous pathologies, pelvic origin extrapelvic varices, and complex vascular malformations. The signatory scientific and medical societies recommend against the routine use of fluoroscopy and other radiation-based imaging in the investigation and treatment of superficial venous disease.

Varicose Veins of the Lower Extremity: Doppler US Evaluation Protocols, Patterns, and Pitfalls.

Venous insufficiency is a cause of substantial morbidity and medical expenditures. Diagnostic US evaluation of venous insufficiency requires a thorough understanding of the venous anatomy, including the deep, superficial, and perforator veins. The highly variable venous anatomy requires that operators use sound judgment to expand on protocol images and thus avoid missing important sources of reflux. The US examination requires specific patient positioning and use of provocative maneuvers. A basic understanding of the pathophysiology of venous insufficiency and the various treatment methods helps to identify key observations so that ineffective treatment methods are not pursued. The examination reports should have greater detail than those for the more common lower extremity deep venous thrombosis evaluation, requiring numeric and narrative descriptions of deep and superficial venous patency, reflux, diameter, and pathways. Potential pitfalls include not recognizing or detecting deep venous reflux, misidentifying common femoral vein reflux as deep venous reflux when the reflux is isolated or related to saphenofemoral insufficiency, not recognizing anterior accessory great saphenous vein (AAGSV) involvement in saphenofemoral insufficiency, not recognizing or reporting great saphenous vein or AAGSV superficialization, not suspecting central venous obstruction, and not realizing when provocative maneuvers were ineffective. With knowledge of the lower extremity venous anatomy, venous insufficiency pathophysiology, basic treatment strategies, protocol best practices, patterns of observation, and diagnostic pitfalls, those who interpret venous insufficiency US studies can perform examinations and deliver reports that help patients receive appropriate treatment. Online supplemental material is available for this article. ©RSNA, 2022.

Relationship between iliofemoral venous stenting and femoropopliteal deep venous reflux

ObjectiveSevere presentations of chronic venous insufficiency can result from reflux or obstruction at the deep venous, perforator, or superficial venous levels. Iliofemoral venous stenting can be used to address central venous obstruction; however, its effects on deep venous reflux (DVR) have remained unclear. The purpose of the present study was to evaluate the effects of iliac vein stenting on femoropopliteal DVR with the hypothesis that ultrasound evidence of DVR would remain absent or would have improved after iliac vein stenting. MethodsThe present study was a retrospective review of patients who had undergone iliofemoral venous stenting from 2013 to 2018. The patients were divided into two cohorts according to the preprocedural presence (group A) or absence (group B) of femoropopliteal DVR. Baseline patient variables were collected, including age, gender, CEAP (clinical, etiologic, anatomic, pathophysiologic) class, presence of concomitant superficial or perforator reflux, deep vein thrombosis history, and additional venous interventions. The primary outcome evaluated was the persistent absence or resolution of DVR on the latest venous duplex ultrasound at follow-up. Other outcomes included the follow-up CEAP classification and the need for secondary deep venous interventions. ResultsA total of 275 consecutive patients had undergone iliofemoral venous stenting. Of the 275 patients, 58 had presented with DVR (group A). A comparison of groups A and B revealed that group A had had a greater likelihood of prior deep vein thrombosis (P = .0001) and a higher frequency of superficial venous ablation. The remaining demographic variables did not differ significantly between the two groups. Of the 58 patients in group A, DVR had resolved at follow-up in 17 (P = .0001). When stratified by level, 7 of these 17 patients had had isolated popliteal reflux. In group B, DVR had developed at follow-up in 6 of the 217 patients. The CEAP class had improved from before intervention (C0, 1.1%; C1, 0.4%; C2, 1.8%; C3, 41.4%; C4, 24.9%; C5, 5.9%; C6, 24.5%) to the latest follow up (C0, 4.9%; C1, 1.9%; C2, 5.7%; C3, 34.2%; C4, 22.8%; C5, 17.1%; C6, 13.3%). Significant improvement had occurred in C6 disease within both groups (group A, 16 of 58 [27.6%; P = .0078]; group B, 19 of 217 [8.8%; P = .0203]). ConclusionsFor patients who undergo iliofemoral venous stenting, DVR could improve if present initially and is unlikely to develop if not present before stenting. A cohort of patients had experienced persistent DVR and warranted further evaluation. Prospective studies are required to corroborate the safety, efficacy, and durability of iliofemoral venous stenting for patients with DVR.

Routine use of concurrent fluoroscopic imaging during superficial endovenous interventions: A position statement of the International Union of Phlebology (UIP), the Australasian College of Phlebology (ACP), the Australia and New Zealand Society for Vascular Surgery (ANZSVS), the American Venous Forum (AVF), the American Vein and Lymphatic Society (AVLS), the European College of Phlebology (ECoP) and the Interventional Radiology Society of

International evidence-based guidelines recommend preoperative duplex ultrasound mapping in the assessment of chronic venous disease, and concurrent ultrasound imaging to guide superficial endovenous interventions such as endovenous laser ablation, radiofrequency ablation, cyanoacrylate adhesive closure, and sclerotherapy (ultrasound-guided sclerotherapy). Other imaging modalities such as venography, alone or in combination with computed tomography scan or magnetic resonance imaging, may be included in the preoperative assessment of a small and select group of patients to exclude central venous obstruction, certain deep venous pathologies, pelvic origin extrapelvic varices, and complex vascular malformations. The signatory scientific and medical societies recommend against the routine use of fluoroscopy and other radiation-based imaging in the investigation and treatment of superficial venous disease.

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

BackgroundSymptomatic 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. MethodsThis 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. ResultsIn 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). ConclusionsStent implantation for CVO that is resistant to standard angioplasty seems safe and effective.

The inside-out technique is safe and effective for thoracic central venous obstruction

BackgroundThoracic central venous obstruction (TCVO) presents a challenging scenario for patients requiring central venous access. The inside-out technique for crossing occluded veins has been described; however, to date, case series have reported on a limited number of patients. The purpose of the present study was to evaluate the indications for, efficacy of, and outcomes with the inside-out technique at a single tertiary academic center, with close attention to the severity of TCVO using the Society of Interventional Radiology (SIR) TCVO classification. MethodsPatients who had undergone central venous access using the inside-out technique were identified from August 2007 to May 2021. The patient demographics, procedure indication, procedural details, SIR TCVO classification, outcomes, and procedure-related complications were recorded. Statistical analysis was performed using analysis of variance. ResultsA total of 221 patients (109 men [49.3%] and 112 women [50.6%]) had undergone 338 inside-out procedures. Of the 221 patients, 49 had undergone the procedure multiple times (25 two times, 11 three times, 13 more than three times). The average patient age was 54.7 ± 14.8 years. The indications (n = 362) for the procedure included dialysis access (n = 230; 63.5%), infusion of parenteral nutrition, antibiotics, chemotherapy, or other medication (n = 81; 22.3%), cardiac access (n = 39; 10.8%), and other (n = 12; 3.3%); more than one indication for 20 procedures. Type 1 SIR TCVO was found during 147 procedures (43.5%), followed by type 4 for 142 (42.0%), type 2 for 36 (10.7%), type 3 for 6 (1.8%), and unable to determine for 7 (2.0%). The access site was the right femoral vein for 322 procedures (95.3%), left femoral vein for 14 (4.1%), and transhepatically for 2 (0.6%). The exit site location was the right supraclavicular region for 274 (81.3%), right subclavicular for 52 (15.4%), left supraclavicular for 3 (0.9%), left subclavicular for 6 (1.8%), and not defined for 2 (0.6%). Types 3 and 4 were associated with longer fluoroscopy times and more contrast compared with types 1 and 2. The median follow-up and device duration was 56.0 days and 76.5 days, respectively. No differences were found in device duration between the SIR TCVO types. Removal of a catheter was documented for 166 patients. The indications for removal included infectious causes (non–catheter-related bacteremia, catheter-related infection or bacteremia) for 70 (42.1%), catheter malfunction for 34 (20.5%), new hemodialysis access for 19 (11.5%), no longer needed for 19 (11.5%), patient removal of the catheter by 13 (7.8%), and replacement of a temporary catheter with a tunneled device for 11 (6.6%). No procedural complications were associated with the inside-out technique or catheter removal. ConclusionsFor a variety of indications, we have shown that the inside-out technique is safe and effective for establishing central venous access in patients with TCVO and can be performed repeatedly. More complex obstructive patterns were associated with longer fluoroscopy times and greater contrast administration. Durability was primarily limited by infectious complications.

Spectrum of Interventional Procedures During Hybrid Central Line Placement in Pediatric Intestinal Rehabilitation Patients With End-Stage Vascular Access.

BackgroundLoss of available central vein access sites for parenteral nutrition delivery represents one of the main indications for intestinal transplantation in children with intestinal failure. Placement of central venous catheters can be challenging in advanced loss of patent venous pathways. We recently described the hybrid technique (interventional plus surgical approach) of central line placement in children. The aim of this study was to describe and analyze the interventions used during the hybrid procedures regarding feasibility, safety and outcome.MethodsWe retrospectively analyzed the course of all children in our intestinal rehabilitation program undergoing hybrid central line placement. We evaluated patients' conditions, interventional techniques and surgical peculiarities as well as outcome.Results203 children were treated in our intestinal rehabilitation program between 2010 and 2021. Due to loss of venous access, hybrid technique was performed in 53 children during 76 interventions. In 40 cases the same vessel was reused via Seldinger technique. Among the 30 ultrasound-guided new vessel punctures, 12 were performed by puncture of collateral vessels. Extended interventions due to thoracic central venous obstruction and/or thrombosis requiring additional access via a femoral vein for rehabilitation of the vascular system was performed during 29 procedures including catheter extraction (1), angioplasties (18), stent placement (1), revascularization (5) and thrombectomy (4). Placement of a central line was not possible in 6 children which eventually underwent extended thoracic/vascular surgery: in three children the previously placed catheter could not be removed, in one child, placement of a thrombectomy-catheter was not possible because of inferior vena cava occlusion, and in two children, revascularization failed. Intestinal transplantation was considered in one patient because of impending loss of vascular access. Two self-limiting minor extravasations and one intervention-associated pericardial effusion occurred.ConclusionsHybrid interventions for central venous catheter placement and vascular rehabilitation enable a high success rate in children with intestinal failure and end-stage vascular access, circumventing the need for intestinal transplantation or advanced surgery. The relevant procedures are complex and require a foresighted and individualized approach with a wide range of interventional techniques. If performed with expertise, this combined interventional/surgical approach is feasible and safe.

Internal jugular to internal jugular vein bypass of symptomatic central vein obstruction.

Central venous obstruction (CVO) often arises among hemodialysis patients with upper extremity access due to a varying number of risk factors. While the true incidence of CVO in hemodialysis patients is unknown, it been reported in the range of 20%-40% in dialysis patients undergoing venograms. In the non-hemodialysis population, chronic central vein obstruction has a compensatory mechanism comprised of numerous collaterals along the chest wall, neck, and mediastinum. However, the presence of an AVF or AVG ipsilateral to a central venous stenosis or occlusion can overwhelm the collateral network due to the significantly elevated blood flow. This may result in severe and debilitating upper extremity and fascial swelling. While ligation results in almost instantaneous symptomatic relief, it does not address the patient's underlying pathologic process and necessitates an additional access. As these patients continue to live longer, our strategies to manage these failing accesses are becoming increasingly complex. The goal of preserving existing access while correcting any symptoms is paramount. Previous case reports have documented various surgical options for preserving an existing access. Our patient is a 49-year-old female with hypertension and end-stage renal disease, on hemodialysis through a right arm arteriovenous (AV) fistula. She had a history of multiple AV fistulae creations in the past, all of which previously thrombosed. Several years after the creation of her most recent fistula, she developed severe throbbing headaches, right arm and facial swelling, right eye lacrimation, and blurry vision. AV fistula angiogram demonstrated right brachiocephalic vein chronic occlusion and endovascular revascularization through both trans-AVF and transfemoral approaches were attempted, but unsuccessful. This case illustrates the success of the creation of an internal jugular-jugular vein bypass to maintain a right arm arteriovenous fistula, while at the same time, correcting the symptoms of a right brachiocephalic vein occlusion.

The Inside-out Technique Is Safe and Effective in Thoracic Central Venous Obstruction

Thoracic central venous obstruction (TCVO) presents a challenging scenario for patients requiring central venous access. The inside-out technique for crossing occluded veins has been described to avoid femoral catheters and to preserve the left-sided thoracic venous vasculature, but case series are limited by number of patients. The purpose of this study was to evaluate the use of the inside-out technique at a single tertiary academic center together with its efficacy and outcome, paying close attention to the severity of TCVO using the Society of Interventional Radiology (SIR) TCVO classification (Figure).

Brachio-azygos transthoracic arteriovenous grafts for hemodialysis patients with bilateral central venous obstruction: A small case series.

It is difficult to find a reliable outflow vein for vascular access in hemodialysis patients with bilateral central venous obstruction. The lower extremity veins are currently used as the most common alternative veins to make a new vascular access. However, in patients not amenable to make lower extremity access, intrathoracic vein should be considered as an outflow vein, but there are limitations in its use due to postoperative complications. We introduce a series of cases that underwent arteriovenous graft operation using an intrathoracic vein, the azygos arch, as an outflow vein. Brachio-azygos transthoracic arteriovenous graft is a surgical procedure that anastomoses the azygos arch and the brachial artery with 7 mm ringed polytetrafluoroethylene graft via lateral thoracotomy without median sternotomy. The chest tubes of the patients were removed on the third postoperative day and they discharged within a week. About 1 month later, hemodialysis was initiated through the BATAVG, and it has been used without access dysfunction. Brachio-azygos transthoracic arteriovenous grafts were performed using the azygos arches without major complications. The azygos arch can be a good alternative outflow vein to make a new vascular access for hemodialysis patients with bilateral central venous obstruction.

Alternant Approach to Manage Patent AVF With Untreatable Venous Hypertension from Central Stenosis

<h3>Introduction and Objective</h3> Arteriovenous fistula (AVF) associated venous hypertension from central venous obstruction is commonly seen to cause dysfunctional dialysis access and severe swelling. It is traditionally managed by a variety of surgical, interventional approaches, but when the central stenosis/occlusion cannot be corrected, focus shifts only to relieve the edema. The most common approach is sacrificing the vein with ligation and starting anew despite risks of non-maturity and/or using a non-autologous conduit. We report a novel approach by translocating a patient's native and "mature" vein to create a new AVF and treat both problems. This minimizes time-to-maturity, quickly establish long-term, autologous vascular access for hemodialysis and simultaneously treat the swollen extremity. <h3>Case Report</h3> 80-year-old female with a functional brachiocephalic AVF had severe and painful venous hypertension due to presumed central vein obstruction. The AVF was created in 2017 and unused until November 2019. It worked for 7 months until developing left upper extremity swelling and pain. She underwent five balloon angioplasty procedures at an outside facility without lasting resolution. In January 2021 her left upper extremity was tense, edematous and significant erythema. The left arm had evolving elephantiasis with Peux D'Orange skin changes, warmth, tenderness, with a distant, but palpable thrill. We attempted resolution via femoral venous access which revealed a >70% stenosis of her subclavian vein close to the innominate junction and near her first rib and clavicle interface. Balloon angioplasty with a 12 × 40mm Conquest balloon at 20 ATM had immediate reversal of her venous hypertension and symptomatic relief. At one month she reported recurrence of swelling and pain. We discussed first rib resection, AVF ligation and/or catheter-only dialysis or starting again. She refused a rib resection. We harvested and excised her large and mature left cephalic vein and translocated it to her right forearm to create a new radial artery to Brachial vein AVF (with a tunneled catheter for acute access). Due to size mismatch, we everted the left cephalic vein to do valvulotomy, and the anastomosis was done in a non-reversed fashion with two end-to-side anastomosis. This simultaneously corrected her venous hypertension and gave her an autologous AVF using her contralateral cephalic vein. At one month, her left upper extremity had complete resolution and the AVF was cleared for access. <h3>Discussion</h3> Venous hypertension and central venous obstruction with a functional AVF can compromise efficient dialysis and be very debilitating leading to AVF ligation and abandonment when it cannot be resolved. This approach offers an accessible technique for salvage of a relatively common AVF complication with high success for cannulation.

Novel technique of stent retrieval after migration to the right heart.

Central venous obstruction in the symptomatic patient is often treated with endovascular stenting. A rare, but serious, complication of this treatment is migration of the stent from the original site of deployment. Treatment of this complication requires either open or endovascular retrieval of the displaced stent. To treat a rare, but potentially devastating, complication, we have presented an effective endovascular method for migrated stent retrieval using a combination of a large bore sheath, balloon, and snare.