Treatment of hemodialysis-related central venous stenosis or occlusion: results of primary Wallstent placement and follow-up in 50 patients

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.

SMART Stent for Salvage of Hemodialysis Access Grafts

PURPOSE

To evaluate the SMART stent for treating angioplasty-resistant hemodialysis access venous stenoses.

MATERIALS AND METHODS

A retrospective study of 64 patients with polytetrafluoroethylene grafts who were treated with the SMART stent at 69 locations in the venous outflow tract was undertaken. Stents were used for elastic recoil after percutaneous transluminal angioplasty, venous rupture, or recurrent stenosis less than 3 months after angioplasty. When angiographic follow-up was available, the degree of in-stent restenosis was measured. Primary patency was determined, and, when applicable, compared with that of previous angioplasty treatments of the same lesion.

RESULTS

The SMART stent was placed in 15 central veins and 54 peripheral veins, with a 98% technical success rate and a 97% clinical success rate. The mean primary access patency times were 14.9 months and 8.9 months in patients who received central and peripheral stents, respectively. In 19 patients whose central or peripheral venous stenoses were previously treated with angioplasty, the mean primary access patency was increased from 2.5 months to 10.6 months after placement of the SMART stent (P = .0003). Angiography in 29 patients after an average of 348 days showed 55% mean in-stent stenosis. The only stent-related complication occurred in a patient who had venous dissection associated with the edge of a SMART stent placed at the elbow.

CONCLUSION

The SMART stent is safe and effective for treating dialysis access venous stenoses that are resistant to standard angioplasty.

Role of CT venography in the diagnosis and treatment of benign thoracic central venous obstruction

Objective

To evaluate the role of CT venography in the diagnosis and treatment of benign thoracic central venous obstruction.

Materials and Methods

Eighteen patients who had undergone both CT venography and digital subtraction venography were prospectively enrolled in this study. The following features were analyzed by two observers: the cause, degree, and extent of venous obstruction; associated thrombosis; and implications for the planning of treatment. CT venography and digital subtraction venography were compared in defined venous segments, and the degree of obstruction, and correlation was expressed using Spearman's rank correlation coefficient.

Results

In all patients, CT venography depicted the causes of obstruction, including extrinsic compression of the left brachiocephalic vein, and mediastinal inflammatory pseudotumor. Interobserver agreement regarding classification of the degree of obstruction was judged as good for CT venography (κ=0.864), and in evaluating this, there was significant correlation between CT venography and digital subtraction venography (reader 1: Rs = 0.58, p < 0.01; reader 2: Rs = 0.56, p < 0.01). In evaluating the status of central veins proximal to long segmental obstruction, and associated thrombosis, CT venography was superior to digital subtraction venography. In half of all patients, the findings of CT venography led to changes in the treatment plan.

Conclusion

The findings of CT venography correlated closely with those of digital subtraction venography, and the former accurately depicted the degree and extent of benign venous obstruction.

Endovascular stent placement in the treatment of upper extremity central venous obstruction in hemodialysis patients

OBJECTIVE

To evaluate the efficacy of stent placement for treating upper extremity central venous obstruction in chronic hemodialysis patients.

METHODS AND MATERIAL

Between January 1999 and October 2001, we inserted metallic stents into the upper extremity central veins of 14 patients with shunt dysfunction and/or arm swelling. The indications for stent placement were stenosis or occlusion of the central vein in the upper extremity used for dialysis. Six of the individuals were diagnosed with subclavian vein stenosis, and 5 with brachiocephalic vein stenosis. Of the remaining 3 patients, 2 had subclavian vein occlusion, and 1 had left brachiocephalic vein occlusion.

RESULTS

All the stent placement procedures were technically successful, and there were no major complications. Follow-up ranged from 2 weeks to 29 months. The 1-, 3-, 6- and 12-month primary stent patency rates were 92.8, 85.7, 50 and 14.3%, respectively. Repeat interventions, including percutaneous transluminal angioplasty and additional stent placement, were required in 9 patients. The 3-, 6-, 12-month, and 2-year assisted primary stent patency rates were 100, 88.8, 55.5 and 33.3%, respectively.

CONCLUSION

Endovascular stent placement is an effective alternative to surgery in patients with shunt dysfunction due to obstruction of an upper extremity central vein. Repeated interventions are usually required to prolong stent patency.

Endovascular treatment of central venous stenoses in patients with dialysis shunts

OBJECTIVE

Evaluation of long-term results of percutaneous treatment of central vein stenoses or occlusions in patients with haemodialysis shunt.

MATERIALS AND METHODS

In 26 patients with haemodialysis shunts and confirmed central vein stenosis or occlusion, 28 primary percutaneous transluminal angioplasties (PTA) and 5 repeated PTAs (re-PTA) were performed; in three patients a stent was implanted - primary in one patient and due to early restenosis after PTA in two patients. To maintain stent patency, 10 re-PTA were performed.

RESULTS

The technical success rate of primary interventions was 96 % (100 % in stenoses and 50 % in occlusions). Primary post-PTA patency rate was 70 % at 3 months, 60 % at 6 months and 30 % at 12 months.

CONCLUSION

PTA with possible stent implantation is a first-choice method in the treatment of stenoses and occlusions of the central venous system. Despite the relatively frequent re-interventions, endovascular treatment is capable to preserve long-term function of the dialysis shunt.

Salvaging prosthetic dialysis fistulas with stents: forearm versus upper arm grafts

OBJECTIVE

We compared results of angioplasty with those of concomitant stent placement to treat thrombosed forearm hemodialysis grafts with results for upper arm grafts.

MATERIAL AND METHODS

Between October 1998 and July 2002, stents were deployed in 61 patients undergoing balloon angioplasty because of venous anastomotic stenosis causing graft thrombosis. Stents were used only in cases of inadequate angioplasty results. Twenty-three forearm grafts and 38 upper arm grafts were treated. All procedures were performed in an endovascular operating suite, with fistulography. Primary and secondary patency rates were analyzed and compared for graft location with the life table method.

RESULTS

Grafts had undergone a mean of 1.56 previous revisions because of thrombosis (forearm: 1.52, upper arm: 1.58; P = NS). Excluding early thrombosis, a single graft infection was the only procedural complication. Cumulative primary patency rate at 3, 6, and 12 months (from stent placement) was 36.4%, 15.6%, and 0%, respectively, for forearm grafts, which was inferior to the 59.5%, 34.0%, and 17.0% primary patency rate observed for upper arm grafts (P =.0307) Secondary patency rate was 40.9%, 40.9%, and 30.7%, respectively, for forearm grafts, and 64.9%, 42.3%, and 19.7% for upper arm grafts (P = NS).

CONCLUSION

Stent deployment can salvage thrombosed dialysis grafts. However, sustained patency occurs infrequently, with better results for upper arm grafts than for forearm grafts. Inasmuch as surgical revision of forearm grafts is usually straightforward, stenting should be reserved for use in high axillary grafts and other sites where surgical repair is difficult.

Central vein obstruction in hemodialysis patients: Results of radiological and surgical intervention

BACKGROUND/AIMS

Symptomatic central venosus obstruction (CVO) in dialysis patients with arteriovenous fistulas (AVFs) leads to significant morbidity and patient inconvenience. We evaluated the results of surgical and radiological interventional treatment of symptomatic central venous obstruction.

METHODS

Clinical data, site and length of vein obstruction, type and outcome of intervention were obtained from patient records. Patency rates of radiological and surgical treatment were calculated using Life Table survival analysis.

RESULTS

In 28 patients with VH, 45 interventions (percutaneous intervention 30; surgical reconstruction 10; AVF closure five) were performed. Mean vessel obstruction length was 4.9 cm, mainly localized in the subclavian vein (55%). Initial clinical success rate of PTA and surgery was 92%, with complications after percutaneous transluminal angioplasty (PTA) on six occasions. Restenosis after PTA was observed in 39%. One-year primary and secondary patency after PTA was 50 and 63%, respectively. One-year primary patency after surgical reconstruction was 75%.

CONCLUSION

Symptomatic CVO in dialysis patients with AVFs can be treated with a high success rate through radiological intervention. Surgical reconstruction is an appropriate alternative method in case of failed PTA.

The role of interventional radiology in management of patients with end-stage renal disease

The aim of the paper is to review the role of interventional radiology in the management of hemodialysis vascular access and complications in renal transplantation. The evaluation of patients with hemodialysis vascular access is complex. It includes the radiology/ultrasound (US) evaluation of the peripheral veins of the upper extremities with venous mapping and the evaluation of the central vein prior to the access placement and radiological detection and treatment of the stenosis and thrombosis in misfunctional dialysis fistulas. Preoperative screening enables the identification of a suitable vessel to create a hemodynamically-sound dialysis fistula. Clinical and radiological detection of the hemodynamically significant stenosis or occlusion demands fistulography and endovascular treatment. Endovascular prophylactic dilatation of stenosis greater than 50% with associated clinical abnormalities such as flow-rate reduction is warranted to prolong access patency. The technical success rates are over 90% for dilatation. One-year primary patency rate in forearm fistula is 51%, versus graft 40%. Stents are placed only in selected cases; routinely in central vein after dilatation, in ruptured vein and elastic recoil. Thrombosed fistula and grafts can be declotted by purely mechanical methods or in combination with a lytic drug. The success rate of the technique is 89-90%. Primary patency rate is 8-26% per year and secondary 75% per year. The most frequently radiologically evaluated and treated complications in renal transplantation are perirenal and renal fluid collection and abnormalities of the vasculature and collecting system. US is often the method of choice for the diagnostic evaluation and management of the percutaneous therapeutic procedures in early and late transplantation complications. Computed tomography and magnetic resonance are valuable alternatives when US is inconclusive. Renal and perirenal fluid collection are usually treated successfully with percutaneous drainage. Doppler US, magnetic resonance angiography and digital subtraction angiography have a principle role in the evaluation of vascular complications of renal transplantation and management of the endovascular therapy. Stenosis, the most common vascular complication, occurs in 1-12% of transplanted renal arteries and represents a potentially curable cause of hypertension following transplantation and/or renal dysfunction. Treatment with percutaneous transluminal renal angioplasty (PTRA) or PTRA with stent has been technically successful in 82-92% of the cases, and graft salvage rate has ranged from 80 to 100%. Restenosis occurs in up to 20% of cases, but are usually amenable to repeated PTRA. Complications such as arterial and vein thrombosis are uncommon. Intrarenal A/V fistulas and pseudoaneurysms are occasionally seen after biopsy, the treatment requires superselective embolisation. Urologic complications are relatively uncommon, predominantly they consist of the urinary leaks and urethral obstruction. Interventional treatment consists of percutaneous nephrostomy, balloon dilation, insertion of the double J stents, metallic stent placement and external drainage of the extrarenal collections.

Surgical treatment of hemodialysis-related central venous stenosis or occlusion: another option to maintain vascular access

BACKGROUND

The most common cause of graft failure in patients undergoing hemodialysis is outflow venous stenosis. Long-term compromise of venous central trunks must be resolved.

PURPOSE

This study was undertaken to evaluate an unusual surgical option, bypass to decompress a long-term vascular graft to the femoral vein, improving venous outflow, alleviating symptoms of venous hypertension, and restoring vascular integrity for dialysis.

PATIENTS AND METHODS

The study included 3 patients with end-stage renal disease with signs and symptoms of dysfunctioning grafts. Angiographic studies showed occlusion or stricture of the central venous tract and venous outflow compromise. All patients had multiple temporary and long-term vascular access sites for hemodialysis, which were revised several times. Venous decompression was performed with a bridge to the ipsilateral femoral vein. A 6 mm reinforced polytetrafluoroethylene graft was tunneled subcutaneously along the thoracoabdominal wall. Patients were released 48 hours after the procedure, and periodic follow-up was carried out to detect changes in graft patency and function.

RESULTS

There were no preoperative or intraoperative complications. Clear improvement in signs and symptoms of venous hypertension were observed. Venous pressures decreased. Average follow-up was 16.3 months. In 1 patient the new graft malfunctioned, and it was revised and repaired at 25 months. The presence of deep venous thrombosis and pulmonary embolism required peritoneal dialysis. Two other patients, with no change in graft patency, died of concomitant disease.

CONCLUSION

Decompression of the femoral vein enables preservation of vascular graft patency and improves symptoms of venous hypertension.

Dilatation and declotting of arteriovenous accesses

The autogenous arteriovenous fistula has long been proven to be the most durable access for hemodialysis and therefore for any therapy based on plasma exchange. Forearm autogenous fistulas are, however, frequently challenging to create, leading less experienced surgeons to create elbow fistulas or even worse, to place prosthetic grafts. Once the arteriovenous access is constructed, stenoses largely located on the venous side frequently occur, leading to thrombosis if they are not detected and preventively treated. Interventional radiology is now the first line and preferred treatment in the majority of cases of vascular access dysfunction. The overall advantages compared with conventional surgery are its minimal invasiveness, better preservation of the patient's venous reserve, and better outcomes for selected indications such as thrombosed autogenous fistulas. Prophylactic dilation of stenoses greater than 50% associated with clinical abnormalities such as flow-rate reduction is warranted to prolong access patency. Stents are placed only in selected cases with clearly insufficient results of dilation but they must never overlap major side veins and obviate future access creation. Thrombosed fistulas and grafts can be declotted by purely mechanical methods or in combination with a lytic drug. The success rates are over 90% for dilation, in central veins radiologists frequently resort to the use of stents. Long-term results after dilation in the largest series are better in forearm native fistulas compared with grafts. The initial success rates for declotting are better in grafts compared with forearm fistulas but early rethrombosis is frequent in grafts so that primary patency rates can be better for native fistulas from the first month's follow-up.

Vascular and cardiac infections in end-stage renal disease

Patients with end-stage renal disease (ESRD) receiving hemodialysis (HD) are vulnerable to intravascular and endocardial infections. These include vascular access infections, vascular stent infections, and bacterial endocarditis. Staphylococcus aureus is the most commonly encountered microorganism in these conditions. Prolonged intravenous antibiotic therapy is often indicated in these infections. Surgical removal of the infected vascular access or stent may be required. Infective endocarditis occurs less frequently in renal transplant recipients than in patients on HD. Although bacterial endocarditis may occur, fungal endocarditis with organisms such as Aspergillus and Candida species occurs with disproportionately high frequency among renal transplant recipients because of immunosuppression. Prolonged intravenous antibiotic or antifungal therapy is indicated, and valve replacement is often necessary.

Recent advances in peripheral angioplasty and stenting

Utilization of percutaneous interventions for arterial and venous occlusive lesions continue to increase. With the progression of the technology supporting these therapeutic measures, the results of these interventions may be expected to improve. In general, a comparison of techniques for revascularization demonstrates similar initial technical success rates for surgery and percutaneous transluminal angioplasty. Angioplasty is often associated with lower procedural morbidity and mortality rates. Conversely, surgery frequently provides greater long-term patency. Late failure of percutaneous therapies may often be treated successfully with reintervention, however. The continued accumulation of experience with PTA and stenting will ultimately define its role in the management of occlusive disease.

Endovascular management of venous thrombotic diseases of the upper torso and extremities

Central venous thrombosis in the upper torso can be either primary, occurring as a result of longstanding extrinsic compression, or secondary, resulting from an acquired intrinsic occlusive disease or foreign body. As in lower extremity deep vein thrombosis (DVT), anticoagulation therapy is the mainstay of therapy in upper torso and upper extremity DVT. However, in the presence of severely symptomatic acute thrombosis, pharmacologic and/or mechanical thrombolytic therapy represent the main invasive form of therapy for these conditions. After clearance of the acute thrombotic component, definitive management in patients with underlying anatomic abnormalities can be undertaken. Primary subclavian axillary vein thrombosis caused by extrinsic obstruction at the thoracic outlet is treated with thrombolytic therapy and anticoagulation followed by surgical decompression, whereas secondary causes of central venous obstruction and thrombosis are usually amenable to endovascular treatment with balloon angioplasty and stent placement. Postoperative interval anticoagulation is usually recommended. In addition to clinical follow-up, imaging follow-up with duplex sonography or conventional venography is usually recommended to assess the presence of restenosis and/or residual compression.

Vascular access problems in dialysis patients: pathogenesis and strategies for management

Repetitive hemodialysis was made possible through the development of a chronic means of accessing the circulation. This was accomplished through the use of arteriovenous fistulae or grafts, using autologous veins or synthetic materials. Although the arteriovenous fistula remains the access of choice, synthetic arteriovenous grafts are used in most patients because of problems with late referral to a nephrologist and poor vasculature. This article describes the means of accessing the circulation for hemodialysis, the pathogenesis of access failure through progressive stenosis followed by thrombosis, methods of detecting access dysfunction before thrombosis, and therapeutic options. Although angiographic or surgical intervention remain the mainstays of management, medical treatments to decrease stenosis and delay thrombosis are currently under investigation.

Treatment of intracranial venous occlusive disease with sigmoid sinus angioplasty and stent placement in a case of infantile multifocal dural arteriovenous shunts

SUMMARY

The infantile dural arteriovenous shunts are multifocal involving different dural sinuses and progress to an occlusive venopathy with sigmoid sinus and/or jugular bulb stenosis and subsequent occlusion. We report a successful angioplasty and stent placement of a sigmoid sinus - jugular bulb stenosis due to venous occlusive disease in a patient with infantile dural arteriovenous shunts. A five-year-old patient presented with status epilepticus due to severe venous congestive encephalopathy. The angiogram revealed multifocal dural arteriovenous shunts, occlusion of the right sigmoid sinus, absence of cavernous sinuses and significant stenosis of the left sigmoid sinus - jugular bulb. By transvenous approach, percutaneous transluminal balloon angioplasty and stent placement of the stenosed left sigmoid sinus - jugular bulb segment was performed. This resulted in a significant decrease of the venous pressure gradient across the stenosis and allowed a dramatic clinical recovery. Dural sinus angioplasty and stent placement appears to be a safe and effective procedure and should be considered in the treatment of the venous occlusive disease associated with infantile dural arteriovenous shunts.

Treatment of stenosis and thrombosis in haemodialysis fistulas and grafts by interventional radiology

BACKGROUND

There are no large series reporting the long-term results after radiological treatment of both stenosis and thrombosis in native fistulas (AVFs) and prosthetic grafts.

METHODS

Between 1987 and 1999, 726 dilations, 135 stent placements and 257 declotting procedures were performed in 209 consecutive forearm AVFs, 74 upper arm AVFs and 156 prosthetic grafts. The stents used were the Wallstent*, the Craggstent*, and the Passager*. Declotting was performed by manual catheter-directed thromboaspiration, with or without previous urokinase infusion.

RESULTS

The initial success rates ranged from 78 to 98%. The rate of significant complications was 2%. Primary patency rates at 1 year were twice as good for forearm AVFs (50%) than for grafts (25%) (P<0.05), and were 34% for upper arm AVFs. Secondary patency rates were similar in the 3 groups at 1 year (80-86%) and at 2 years (68-80%). Reintervention was necessary every 18 months in forearm AVFs compared to every 9 months in grafts (P<0.05). Thrombosed grafts fared worse than failing grafts. Accesses of less than 1 year's duration needed more reinterventions than older accesses (every 16 months versus 30 in forearm AVFs, every 7 months versus 13 in grafts, P<0.05).

CONCLUSIONS

The percutaneous treatment of stenosis and thrombosis in haemodialysis access achieves patency rates similar to those reported in the surgical literature and confirms that grafts must be avoided as much as possible given their poorer outcome, especially after the first thrombosis. Poorer outcome is also demonstrated in accesses of less than 1 year's duration.