Prevention of recurrent central venous stenosis using endovascular irradiation following stent placement in hemodialysis patients

An overview of in-stent restenosis in iliofemoral venous stents

BACKGROUND

Although endovenous stents have been associated with overall low morbidity, they can require reinterventions to correct stent malfunction due to in-stent restenosis (ISR). ISR has often occurred iliofemoral venous stents but has not been well described. It has been reported to develop in >70% of patients who have undergone iliofemoral venous stenting. We sought to provide an overview of ISR in iliofemoral venous stents, including the pathologic, diagnostic, and management considerations and the identification of several areas of potential research in the future.

METHODS

A search of reported English-language studies was performed in PubMed and the Cochrane Library. "In-stent restenosis," "vein," "venous," "iliac," and "iliofemoral" were used as keywords. The pertinent reports included in the present review had addressed the pathology, diagnosis, and current management options for ISR.

RESULTS

ISR refers to the narrowing of the luminal caliber of the stent owing to the development of stenosis inside the stent itself. ISR should be differentiated from stent compression. Two main types of ISR have been described: soft and hard lesions. These lesions respond differently to angioplasty. Stent inflow and shear stress are important factors in the development of ISR. The treatment options available at present include balloon angioplasty (hyperdilation or isodilation), laser ablation, atherectomy, and Z-stent placement.

CONCLUSIONS

Reintervention for ISR should be determined by the presence of residual or recurrent symptoms and not simply by a numeric value obtained from an imaging study. Overall stent occlusion due to ISR is rare, and no role exists for prophylactic angioplasty to treat asymptomatic ISR. The current treatment options for ISR are mostly durable and effective. However, more research is needed on methods to prevent the development of ISR. The role of antiplatelet and anticoagulant agents in the prevention of ISR requires further investigation, with particular attention to unique subset of patients (after thrombosis vs nonthrombotic iliac vein lesions). For high-risk, post-thrombotic patients, anticoagulation can be considered to prevent ISR. The role of triple therapy (anticoagulation and dual antiplatelet therapy) in the prevention of ISR remains unclear.

Radiological Central Vein Treatment in Vascular Access

In the last decades, the percutaneous interventional approach for the treatment of central venous obstructions (CVO) has become increasingly popular as the treatment of first choice because of its minimal invasiveness and reported success rates. CVOs are caused by a diverse spectrum of diseases which can be broadly categorized into two principal eliciting genera, either benign or malignant obstructions. The large group of benign venous obstructions includes the increasing number of end-stage renal disease patients with vascular access related complications. Due to the invasiveness and complexity of thoracic surgery for benign CVOs, the less invasive percutaneous interventional therapy can generally be considered the preferred treatment option. Initially, the radiological intervention consisted of balloon angioplasty alone, subsequently additional stent placement was applied. This was advocated as either primary placement or secondary in cases of elastic recoil or residual stenosis after percutaneous transluminal angioplasty (PTA). The efficacy of angioplasty of CVO in patients with vascular accesses, either with or without stenting, has been addressed by various studies. Overall, reports indicate an initial technical and clinical success rate above 95% and satisfactory patency rates. However, systematic follow-up and frequent re-interventions are necessary to maintain vascular patency to achieve long-term success.

Central vein stenosis

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

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

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

Vascular Access Flow Reduction for Arteriovenous Fistula Salvage in Symptomatic Patients with Central Venous Occlusion

Purpose

Vascular access patients with central vein (CV) stenosis or occlusion may have significant symptoms. Treatment is generally by balloon angioplasty, with or without stenting. However, CV lesions may not be correctable and when treated, tend to recur. Surgical bypass of CV obstruction is a major procedure and ligation of the access may leave the patient dependent on catheter dialysis. We review a precision inflow banding procedure to limit vascular access flow and pressure for symptomatic patients with CV obstruction while preserving access functionality.

Materials and Methods

All individuals with symptomatic CV occlusive disease who underwent an autogenous vascular access inflow restriction procedure by the two senior authors were identified. All had failed attempts to correct CV lesions by angioplasty and stent placement. A precision banding procedure was used for access inflow reduction with the addition of real-time intravascular flow monitoring.

Results

Twenty-two patients were identified. Ages were 22–72 years (mean=43 years). Nine patients (40.9%) were women, and 8 (36.4%) obese. Mean access flow was 1640 mL/minute before banding decreased to 820 mL/minute after banding (P<.01). All patients had access salvage. Swelling resolved promptly in 20 patients and was markedly improved in two individuals. Three patients underwent aneurysm repair with simultaneous inflow banding and decreased intra-access pressure after flow restriction. Two fistulas failed at eight and 13 months. Mean follow-up was 8 months.

Conclusions

The symptoms of hemodialysis vascular access patients associated with non-correctable central venous lesions resolved successfully and their access was maintained using a precision inflow banding procedure.

Central vein stenosis: current concepts

Central vein stenosis (CVS) is a common complication of the central venous catheter (CVC) placement. The prevalence of CVS has mostly been studied in those who present with symptoms such as swelling of the extremity, neck and breast. CVS compromises arteriovenous access and can be resistant to treatment. A previous history of CVC placement is the most important risk factor for the development of CVS later. Pacemaker and defibrillator wires are associated with a high incidence of CVS. Increasingly liberal use of peripherally inserted central catheters (PICC) is likely to increase the incidence of CVS. The trauma and inflammation related to the catheter placement is thought to result in microthrombi formation, intimal hyperplasia and fibrotic response, with development of CVS. Treatment of CVS by endovascular procedures involves angioplasty of the stenosis. An elastic or recurrent stenosis may require a stent placement. The long-term benefits of the endovascular procedures, although improved with newer technology, remain modest. Surgical options are usually limited. Future studies to explore the pathogenesis and the use of novel therapies to prevent and treat CVS are needed. The key to reducing the prevalence of CVS is in reducing CVC placement and placement of arteriovenous accesses prior to initiating dialysis. Early referral of the patients to the nephrologists by the primary care physicians is important. Timely vein mapping and referral to the surgeon for fistula creation can obviate the need for a CVC and decrease incidence of CVS.

Central vein stenosis: a nephrologist's perspective

Central vein stenosis is commonly associated with placement of central venous catheters and devices. Central vein stenosis can jeopardize the future of arteriovenous fistula and arteriovenous graft in the ipsilateral extremity. Occurrence of central vein stenosis in association with indwelling intravascular devices including short-term, small-diameter catheters such as peripherally inserted central catheters, long-term hemodialysis catheters, as well as pacemaker wires, has been recognized for over two decades. Placement of multiple catheters, longer duration, location in subclavian vein, and placement on the left-hand side of neck seem to predispose to the development of central vein stenosis. Endothelial injury with subsequent changes in the vessel wall results in development of microthrombi, smooth muscle proliferation, and central vein stenosis. Central vein stenosis is often asymptomatic in nondialysis patients, but can result in edema of ipsilateral extremity and breast when challenged by increased flow from an arteriovenous fistula or arteriovenous graft. Bilateral central vein stenosis or superior vena cava stenosis can produce a clinical picture of superior vena cava syndrome, associated with engorgement of face and neck. Endovascular interventions are the mainstay of management of central vein stenosis. Percutaneous angioplasty and stent placement for elastic and recurring lesions can restore the functionality of the vascular access, at least temporarily. Frequent or multiple interventions are usually required. In recalcitrant cases, surgical bypass of the obstruction is an option. In resistant cases with severe symptoms, occlusion of the functioning vascular access will usually provide relief of symptoms. Further study of mechanisms of development of central vein stenosis and search for a targeted therapy is likely to lead to better ways of managing central vein stenosis. Prevention of central vein stenosis is the key to avoid access failure and other complications from central vein stenosis and relies upon avoidance of central vein stenosis placement and timely placement of arteriovenous fistula in prospective dialysis patient.

Central vein obstruction in vascular access

Central venous obstruction has become a major problem because of the frequent need for central venous catheters in haemodialysis patients. This article discusses the epidemiology and clinical features of central venous obstruction and the different surgical and interventional alternatives for its treatment.

UNRESOLVED ISSUES IN DIALYSIS: Long-Term Management of the Tunneled Venous Catheter

Despite their propensity for significant complications, tunneled central venous catheters have become a common means of vascular access in the United States for patients requiring maintenance hemodialysis for end-stage renal disease (ESRD). Reasons for their use include advanced patient age, peripheral vascular disease (arterial and venous), late referral for creation of vascular access, and more importantly, the lack of an interdisciplinary service line on vascular access among vascular surgeons, radiologists, and nephrologists. This review article summarizes complications commonly encountered in dialysis patients who use tunneled central venous catheters for vascular access-mainly thrombosis, stenosis, and infection. Special attention is given to novel approaches for the prevention of catheter-associated infections. Effective prevention and timely treatment of common catheter-associated complications can reduce the substantial morbidity associated with the use of these devices. However, these measures should not detract from the goal of avoiding or limiting the long-term use of catheters, thereby optimizing vascular access management by ensuring the timely availability of functioning arteriovenous fistulas.

Sharp Central Venous Recanalization by Means of a TIPS Needle

The purpose of this study was to perform an alternative technique for recanalization of a chronic occlusion of the left brachiocephalic vein that could not be traversed with a guidewire. Restoration of a completely thrombosed left brachiocephalic vein was attempted in a 76-year-old male hemodialysis patient with massive upper inflow obstruction, massive edema of the face, neck, shoulder, and arm, and occlusion of the stented right brachiocephalic vein/superior vena cava. Vessel negotiation with several guidewires and multipurpose catheters proved unsuccessful. The procedure was also non-viable using a long, 21 G puncture needle. Puncture of the superior vena cava (SVC) at the distal circumference of the stent in the right brachiocephalic vein/superior vena cava, however, was feasible with a transjugular intrahepatic portosystemic shunt (TIPS) set under biplanar fluoroscopy using the distal end of the right brachiocephalic vein as a target, followed by balloon dilatation and partial extraction of thrombotic material of the left brachiocephalic vein with a wire basket. Finally, two overlapping stents were deployed to avoid early re-occlusion. Venography demonstrated complete vessel patency with free contrast media flow via the stents into the SVC, which was reconfirmed in follow-up examinations. Immediate clinical improvement was observed. Venous vascular recanalization of chronic venous occlusion by means of a TIPS needle is feasible as a last resort under certain precautions.

Centered endovascular irradiation to prevent postangioplasty restenosis of arteriovenous fistula in hemodialysis patients; Results of a feasibility study

PURPOSE

To report follow-up results of a prospective trial on centered endovascular gamma-irradiation (CEGI) after percutaneous transluminal angioplasty (PTA) for stenosis of arteriovenous fistula in hemodialysis patients.

METHODS AND MATERIALS

Eight patients receiving PTA for recurrent (n = 4) or de novo arteriovenous fistula stenoses were treated with CEGI with iridium-192 (14 Gy). Angiography was performed after 6 and 12 months or if problems reoccurred during hemodialysis. Parameters of hemodialysis and duplex sonography were determined the day before and after PTA and after 1, 3, 6, 9, and 12 months.

RESULTS

CEGI was performed successfully and without complications in seven patients. In six patients, restenosis occurred 6-52 weeks (mean 20.8 +/- 17.9 weeks) after PTA and required PTA. Parameters of hemodialysis and duplex sonography deteriorated during follow-up.

CONCLUSIONS

Centered endovascular gamma-irradiation with iridium 192 immediately after PTA of fistula stenoses was a safe and feasible method but did not prevent restenosis.

Residual Stenosis Poststenting and Subsequent Decrease in the Proximal Reference Diameter Are Correlated:Excessive Axial Wall Stress Is a Plausible Explanation

PURPOSE

To test the hypothesis that edge restenosis in stented lesions might be due to an increase in axial wall stress in the adjacent proximal vessel segment by examining whether the proximal reference diameters of conventionally stented lesions are reduced at follow-up and whether this reduction depends on the degree of residual stenosis poststenting.

METHODS

The literature published in the past 5 years dealing with restenosis following implantation of standard stents was screened for the availability of (1) reference vessel diameters poststenting, (2) mean residual stenosis poststenting, and (3) mean reference vessel diameters at follow-up in the same patients or groups of patients. Data collected from 11 publications were pooled and used to compute the change in reference segment diameter over time. These differences were compared to the residual stenosis poststenting by nonlinear regression.

RESULTS

The reduction in the mean reference diameters over time and the mean residual stenosis poststenting appear to be strongly correlated (r2 = 0.838), which supports the idea that the evolution of a stenosis adjacent to a stent margin depends on the severity of the residual stenosis.

CONCLUSIONS

This finding indicates that edge restenosis might be due to excessive axial wall stress. It may also explain, at least partly, why edge restenosis is observed with catheter-based brachytherapy and radioactive or drug-eluting stents.