Central venous stenosis in a transplant patient due to thyroid pathology: A teachable moment

Central venous stenosis is a well-recognized complication of central venous catheter use in hemodialysis patients, which may present with significant swelling of the upper limbs, neck, and face. Here, we describe a renal transplant recipient previously on hemodialysis, who underwent endovascular intervention for central venous stenosis after presenting with facial swelling and exertional dyspnoea. His symptoms continued to progress, however, until the underlying thyroid pathology was recognized. Ruling out the possible mimics of central venous stenosis is important in preventing unnecessary intervention. This case highlights the role of specialty bias in the process of diagnosis.

[Diagnostics and endovascular treatment of venous diseases]

In venous disease, acute thromboses and chronic venous insufficiency have the highest health economics relevance. Duplex sonography is the first line diagnostic assessment tool, while cross-sectional imaging is employed as a supplementary method. Due to the availability and examination times computed tomography is preferred in the emergency setting and is supplemented by magnetic resonance imaging (MRI) for specific questions. Endovascular treatment procedures are increasingly becoming available in addition to classical conservative treatment methods.

Organisation of a Radiological Vascular access Unit

An interventional vascular access unit is usually part of an interdisciplinary centre, including departments of nephrology, vascular surgery, angiology and interventional radiology. We present recommendations on quality control, equipment and diagnostic and interventional techniques for the treatment of vascular access insufficiency.

Radiological Assessment of Vascular access in Haemodialysis Patients

Clinical examination is still the most important diagnostic tool and duplex ultrasonography is the imaging method of first choice. Radiological assessment of vascular access for haemodialysis includes preoperative analysis of vessel anatomy and postoperative surveillance for access maturation as well as diagnosis in vascular access insufficiency. Compared to ultrasonography digital subtraction angiography is superior for the evaluation of the central veins and allows diagnosis and treatment in one session. Computed tomography should only be used in patients with inconclusive ultrasonography results, for example, for the assessment of the central veins and visualization of the vascular tree. Gadolinium-enhanced magnetic resonance imaging is no longer recommended in dialysis patients, because it may trigger nephrogenic systemic fibrosis. In patients with a history of previous central venous catheters additional preoperative imaging of the central veins should be performed. In this article we review the different radiological imaging methods for preoperative assessment and suspected vascular access dysfunction.

Stent grafts for central venous occlusive disease in patients with ipsilateral hemodialysis access

PURPOSE

To assess long-term outcomes of stent grafts in patients with symptomatic central venous stenoses and occlusions ipsilateral to hemodialysis grafts or fistulas.

MATERIALS AND METHODS

The study included 52 of 55 consecutive patients with symptomatic stenoses of the central veins draining upper limb dialysis access grafts or fistulas treated with stent grafts. Indications for stent grafts were poor angioplasty results, rapid recurrence, or total occlusion. Endpoints were lesion patency and access patency following intervention. Mean follow-up was 25 months with a median of 24 months and 1.25 additional procedures per patient year. Patency rates were calculated using Kaplan-Meier analysis.

RESULTS

All stent grafts were successfully deployed. The lesion patency rates at 6, 12, 24, and 36 months after intervention were 60%, 40%, 28%, and 28%. The access patency rates at 6, 12, 24, and 36 months after intervention were 96%, 94%, 85%, and 72%. There was one major complication and no minor complications. In 40 patients (77%), the internal jugular vein confluence was covered by the stent graft. In five patients, the dialysis circuits became occluded, with no clinical sequelae in four; one patient was lost to follow-up. The contralateral brachiocephalic vein was covered in three patients (6%), preventing contralateral access construction in one patient.

CONCLUSIONS

Central vein stent graft placement in patients with hemodialysis access is associated with prolonged access patency. Coverage of major vein confluences, which occurred in 83% of the patients in this series, can compromise future access and should be avoided whenever possible by careful technique.

Vascular pediatric interventional radiology

Interventional radiology procedures are increasingly in demand in both the adult and pediatric populations. Pediatric procedures mirror many of the adult procedures but with increased complexity due to many considerations, notably patient size. This article reviews the various vascular pediatric interventional procedures. The aim is to provide a greater exposure to the possible treatment options for pediatric patients and to facilitate understanding of the success and complications rates related to various interventions.

Endovascular Treatment of Dysfunctional Hemodialysis Catheters

Hemodialysis-catheter dysfunction is a common clinical condition in nephrology. Like other central venous devices, hemodialysis-catheters show a disposition for partial or complete thrombotic obstruction and fibrin sleeve formation. Thrombolytic infusion is recommended as therapy of first choice. Alternative interventional strategies include over-the-wire catheter exchange, mechanical fibrin sleeve stripping with a snare and angioplastic sleeve disruption. Those approaches show extremely variable results with mediocre long-term patency rates. Therefore, catheter-avoiding strategies should be considered in detail and AV-fistula creation preferred.

Endovascular Intervention for Central Venous Cannulation in Patients with Vascular Occlusion after Previous Catheterization

Objectives

This study was designed to assess endovascular intervention for central venous cannulation in patients with vascular occlusion after previous catheterization.

Methods

Patients referred for endovascular management of central venous occlusion during a 42-month period were identified from a regional endovascular database, providing prospective information on techniques and clinical outcome. Corresponding patient records, angiograms, and radiographic reports were analyzed retrospectively.

Results

Sixteen patients aged 48 years (range 0.5–76), including 11 females, were included. All patients but 1 had had multiple central venous catheters with a median total indwelling time of 37 months. Eleven patients cannulated for hemodialysis had had significantly fewer individual catheters inserted compared with 5 patients cannulated for nutritional support (mean 3.6 vs. 10.2, p<0.001) before endovascular intervention. Preoperative imaging by magnetic resonance tomography (MRT) in 8 patients, computed tomography (CT) venography in 3, conventional angiography in 6, and/or ultrasonography in 8, verified 15 brachiocephalic, 13 internal jugular, 3 superior caval, and/or 3 subclavian venous occlusions. Patients were subjected to recanalization (n=2), recanalization and percutaneous transluminal angioplasty (n=5), or stenting for vena cava superior syndrome (n=1) prior to catheter insertion. The remaining 8 patients were cannulated by avoiding the occluded route.

Conclusions

Central venous occlusion occurs particularly in patients under hemodialysis and with a history of multiple central venous catheterizations with large-diameter catheters and/or long total indwelling time periods. Patients with central venous occlusion verified by CT or MRT venography and need for central venous access should be referred for endovascular intervention.

Central Vein Stenosis or Occlusion Associated with Cardiac Rhythm Management Device Leads in Hemodialysis Patients with Ipsilateral Arteriovenous Access: A Retrospective Study of Treatment Using Stents or Stent-Grafts

Purpose

Symptomatic central vein stenosis commonly occurs when cardiac rhythm management device (CRMD) leads are placed via the subclavian vein ipsilateral to arteriovenous (AV) hemodialysis (HD) access. The purposes of this study were to determine the outcomes, complications, and patency following stenting of CRMD lead-associated central vein stenosis or occlusion, and to determine the effect of stents on CRMD function.

Methods

Fourteen HD patients with AV access and an ipsilateral CRMD were treated with stents for symptomatic central vein stenosis or occlusion following inadequate response to angioplasty from January 2005 to December 2009. Subsequent access interventions, complications, and outcomes were reviewed retrospectively. Cardiology records were examined to assess CRMD function.

Results

Treatment of stenosis or occlusion with angioplasty and stenting resulted in 100% procedural success and no complications. At 6 and 12 months, respectively, primary patency rates were 45.5% and 9.0%; primary-assisted patency rates were 90.9% and 80.0%; secondary patency rates were 100% and 90.0%. There were 42 repeat interventions performed in 12 patients; five received additional stents. The mean number of subsequent interventions was 3.2 per patient (2.1 per patient-year). All CRMD testing demonstrated normal function with no device or lead failure. Seven of the 14 subjects died resulting in a 35.3% annual mortality rate. No deaths were attributable to dysrhythmia or CRMD failure and no patient required CRMD removal or exchange.

Conclusions

Placement of stents for CRMD lead-associated stenosis or occlusion yields high success and low complication rates with no effect on CRMD function. Patency rates are similar to those reported in other series of central venous stents.

Dialysis access: an increasingly important clinical issue

Dialysis access, including vascular access for hemodialysis and peritoneal access for peritoneal dialysis, is critical in the clinical care of patients with end-stage renal disease. It is associated with increases in morbidity, mortality, and health care costs. A number of problematic issues are involved, some of which are addressed in this paper with reference to the most recent publications, including: the inappropriately low prevalence of peritoneal dialysis in Western countries, which is relevant to access placement in the pre-dialysis stage; the excessively high use of central venous catheters in incident and prevalent dialysis patients; the diagnosis and treatment of steal syndrome; the advantages and limitations of antiplatelet therapy; and finally, the correct pre-operative evaluation and subsequent surveillance of the vascular access.

[Venous interventions. Part 2: Thromboses of the upper torso and mesenteric veins]

This article focuses on the percutaneous treatment options of venous thromboses and occlusions. Interventional therapy modalities for mediastinal, brachial, axillar, cerebral, and mesenteric thromboses are reviewed. Stenoses of the superior vena cava are most often caused by mediastinal malignomas. Balloon angioplasty together with stent implantation is an effective method for revascularisation in cases of upper venous congestion. Benign central venous stenoses are common in dialysis patients for whom interventional therapy using balloon angioplasty has proven excellent results. In the treatment of insufficient dialysis access, percutaneous techniques represent the first-choice option. Regarding cerebral and mesenteric thrombosis, interventional therapy is restricted to selected individual cases.