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Do Stents Have A Role in Vascular Access

Tze-Woei Tan, MD

Assistant Professor of Surgery

Vascular & Endovascular Surgery

Louisiana State University Health Shreveport

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John C. McDonald Transplant & Dialysis Access Symposium

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Disclosures

  • I have no relationship(s) with industry to disclose relevant to the content of this CME activity.

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Learning Objective

  • Review indications and outcome for the use of stents at Graft Vein Anastomosis

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  • Review indications and outcome for use of stents in Central Venous Stenosis

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Background (Peripheral Vein)

  • Arteriovenous graft (AVG) remains major type of vascular access

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  • Progressive development of neointimal hyperplastic stenosis in the outflow tract

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  • Most commonly occur at venous anastomosis, venous outflow vein, central vein and arterial anastomosis

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  • Early detection and treatment of hemodynamically significant stenosis

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Background (Peripheral Vein)

  • Hemodynamic significant outflow stenosis (>50% diameter reduction & hemodynamic/ functional/ clinical abnormality)
    • Decreases blood flow
    • Risk of access thrombosis

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  • 90% of thrombosed AVG are associated with stenosis, predominantly in the outflow, venous anastomosis and central vein

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Balloon angioplasty (PTA) in Peripheral Vein

  • Non-thrombosed AVG
    • Reduce rate of thrombosis
    • Better outcomes when it is performed in functioning graft
  • Thrombosed AVG
    • Underlying stenosis in 90%
    • Identification & treatment of stenosis are essential

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  • PTA of stenoses
    • 6-month primary patency of 40-50% with patent AVG
    • 3-month patency 30-40% after percutaneous thrombectomy

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  • Outcomes between PTA and stent were similar in early studies

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Significant stenosis at graft venous anastomosis despite PTA

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Placement of bare metal stent

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Stents

  • Not routinely recommended in peripheral vein for dialysis access

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  • Bare metal stent
    • Extensive epithelialization
    • In-stent restenosis

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  • Cover stent graft
    • Expansive
    • End-stent stenosis
    • Risk of infection

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KDOQI guideline 2006

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Stent in Peripheral Vein

Yevzlin A , and Asif A CJASN 2009;4:996-1008

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RCT PTA vs. Stent graft

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Meta-analysis (Stent vs. PTA)

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RENOVA Trial

  • Multicenter prospective randomized trial
  • 270 patients at 28 centers
  • Inclusion: AVG with >50% peripheral venous anastomotic stenosis
  • 138 stent graft (FLAIR® stent graft) vs. 132 PTA

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  • Results:
    • Access circuit primary patency (24.1% vs. 10.3%, p=.005)
    • Stenosis requiring intervention (60.1% vs. 82.6%, p<.001)
    • No difference in adverse event

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Haskal ZJ. Twelve month results of the RENOVA trial: A prospective multi-center randomized controlled trial of the FLAIR® endovascular stent graft versus balloon angiopalsty in dialysis access. Presented at the 2013 SIR meeting

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RENOVA Trial Update

Saad TF. Update on RENOVA Trial. ASDIN 10th meeting, Phoenix, AZ 2014

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RENOVA Trial Update

Saad TF. Update on RENOVA Trial. ASDIN 10th meeting, Phoenix, AZ 2014

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Background (Central Vein)

  • Central vein
    • Upper extremity: subclavian vein, innominate vein & superior vena cava
    • Lower extremity: iliac vein & inferior vena cava

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  • Central vein stenosis/ occlusion
    • Asymptomatic
    • Venous hypertension and swelling
    • Access dysfunction

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  • Risk factor: central venous catheter, cardiac rhythm device

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Stent in Central Vein

  • Stent placement in the central vein is less controversial
    • Surgical intervention difficult
    • More susceptible to recoil

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Stent in Central Vein

Yevlin A and Asif A. Clin J Am Soc Nephrol 4;996-1008,2009

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Stent in Central Vein

  • No conclusive evidence

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  • Problems with stent in central veins
    • Stent fracture, migration and rish of thrombosis
    • Infection
    • Compromising other venous outflow
      • Future access surgery
      • SVC syndrome

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Central Occlusion with arm swelling

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Subclavian/ Brachiocephalic vein stent placement

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Hemodialysis Reliable Outflow Graft (HERO)

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Stent graft for Pseudoaneurysm

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Summary

  • Peripheral lesion
    • No evidence for routine stent placement
    • PTA still standard of care
    • Refractory lesion, recurrence < 3 month
    • Might be beneficial for venous anastomotic lesions in AVG
    • Should not interfere with future surgical revision or new access

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Summary

  • Central lesion
    • More acceptable
    • Acute recoil after PTA
    • Recurrence in less than 3 months after PTA

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Thank you

  • Question?

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