Advertisment

Indian Journal of Nephrology About us |  Subscription |  e-Alerts  | Feedback | Login   
  Print this page Email this page   Small font sizeDefault font sizeIncrease font size
 Home | Current Issue | Archives| Ahead of print | Search |Instructions |  Editorial Board  

Users Online:559

Official publication of the Indian Society of Nephrology
  Search
 
  
 ~  Similar in PUBMED
 ~  Search Pubmed for
 ~  Search in Google Scholar for
 ~  Article in PDF (533 KB)
 ~  Citation Manager
 ~  Access Statistics
 ~  Reader Comments
 ~  Email Alert *
 ~  Add to My List *
* Registration required (free)  

 
  Introduction
   Percutaneous End...
  Conclusion
   References
   Article Tables

 Article Access Statistics
    Viewed598    
    Printed31    
    Emailed0    
    PDF Downloaded73    
    Comments [Add]    

Recommend this journal

 


 
  Table of Contents  
COMMENTARY
Year : 2022  |  Volume : 32  |  Issue : 6  |  Page : 528-530
 

Endovascular procedures in nephrology


1 Interventional Nephrologist, Department of Interventional Nephrology and Interventional Radiology, Lilavati Hospital and Research Centre, Mumbai, Maharashtra, India
2 Interventional Radiologist, Department of Interventional Nephrology and Interventional Radiology, Lilavati Hospital and Research Centre, Mumbai, Maharashtra, India

Date of Submission17-Jul-2020
Date of Acceptance03-Feb-2021
Date of Web Publication06-Dec-2022

Correspondence Address:
Hemant J Mehta
53A, Heera Panna, Bhulabhai Desai Road, Mumbai - 400 026, Maharashtra
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijn.ijn_258_20

Rights and Permissions



How to cite this article:
Mehta HJ, Warawadekar GM. Endovascular procedures in nephrology. Indian J Nephrol 2022;32:528-30

How to cite this URL:
Mehta HJ, Warawadekar GM. Endovascular procedures in nephrology. Indian J Nephrol [serial online] 2022 [cited 2023 Feb 8];32:528-30. Available from: https://www.indianjnephrol.org/text.asp?2022/32/6/528/362869



  Introduction Top


The scope of diagnostic and interventional nephrology (IN) has been well defined.[1] Endo is a prefix from Greek ἔνδον endon meaning "inside the blood vessel." There has been a marked change in the vascular access profile of patients receiving hemodialysis (HD). As patients are surviving longer on HD, maintaining a functional vascular access has become a major clinical challenge. Until recently, the dialysis vascular access care was mainly "reactive" and dependent on surgical methods. The suitability of HD patients for open surgical techniques and timely interventions are two major barriers to maintaining vascular access patency and avoid disruption of HD. The evolution of endovascular procedures became essential to improve overall quality of care. These endovascular procedures have traditionally been the domain of interventional radiology or vascular surgery, but in the last two decades, the field of IN has established itself as a subspecialty in the developed countries and gaining momentum in the developing countries.


  Percutaneous Endovascular Procedures Top


Arteriovenous fistula (AVF) is preferred over arteriovenous graft (AVG) as a long-term vascular access and needs monitoring for maturation and early dysfunction. The common underlying pathology is development of neointimal hyperplasia that results in stenosis, decreased blood flow, and eventual thrombosis. The endovascular methods including angioplasty, thrombectomy, mechanical or pharmaco-mechanical thrombolysis, and stent placement, have become a first-line treatment option to salvage a failing access.[2] As per 2019 KDOQI Vascular Access Practice Guidelines,[3] access stenosis of ≥50% when associated with clinical or physiologic abnormalities such as an altered venous/arterial circuit pressure (venous pressure >250 mm Hg, arterial line pressure <250 mm Hg), prolonged bleeding (>30 min) after needle removal, trends suggesting decreased access flow (<500 mL in AVF, <600 mL in AVG or >20% reduction in flow from baseline) and "inadequate dialysis" (kt/v <1.2 or persistent URR <65%) should be considered for endovascular intervention [Table 1].
Table 1: Suggested interventions in hemodialysis vascular access

Click here to view


Interventional nephrology (IN) is an evolving field in India and would suggest using this commentary to highlight critical elements to developing a new field and maintaining collegiality and professionalism with colleagues from the multidisciplinary team.

Scope of endovascular procedures includes

  1. Primary access failure:


    1. Percutaneous angioplasty (PTA) of stenosis
    2. Embolization of accessory veins
    3. Ligation of accessory veins


  2. Maintenance procedures:


    1. PTA
    2. Thrombectomy––mechanical and pharmaco- mechanical
    3. Stent placement––various types, role of bare metal vs. covered stents
    4. Endovascular therapy for steal/high flow access


  3. Treatment of Central vein stenosis


    1. PTA/stent therapy (Primarily)
    2. Inside out technique/device (Newer technique for total central venous occlusion)


  4. Advanced procedures––Endovascular AVF
  5. Endovascular treatment of aneurysms/pseudoaneurysm
  6. Managing complications––team approach including vascular surgeon and interventional radiologist is helpful.


"Don't nephrologists perform any procedures?" is a usually asked question. As more nephrologists get involved in the procedures, volume and expertise improve. Several opportunities exist in India for training, including in centre training, and several workshops conducted all-round the year. International Society of Nephrology sponsored fellowship in IN may be explored by interested candidates. The goal should be to train in those procedures, relevant to the location of practice. The young nephrologists are very much interested in learning these procedures, as per author's personal experience.

  1. Training and Certification––Procedural, radiation safety, conscious sedation


    1. Role of standardizing training programs, curriculum, and a certifying body
    2. CME––programs––meeting, and hands-on workshops


  2. Safety––Role of Quality improvement process
  3. Maintaining a multidisciplinary approach to care
  4. Maintaining records


Failure to mature (FTM) of AVF occurs in 20%–60% of AVFs.[4] Beathard showed the causes of FTM as either venous stenosis or secondary vein which takes the blood away from main AVF circuit. The PTA of stenosis and obliteration of secondary vein can be performed by a nephrologist.[5]

The AVF angioplasty can be performed under fluoroscopic or ultrasound guidance in select cases. New techniques of PTA using drug-eluting balloon (DEB) is thought to work due to the antiproliferative effects of drugs on the smooth muscle cells in blood vessels. In vivo, venous smooth muscle cells are thought to be more susceptible to these effects,[6] and can slow down the growth of new smooth muscle cells in the vessel wall that may lead to restenosis.

Nitinol and polytetrafluoroethylene covered stent placement to treat HD arteriovenous access stenosis have been tried. Stent grafts can convert unusable upper arm AVF into a functioning HD access as reported by Bavare et al.[7] The authors of this article have used drug-eluting coronary stent (DES) on the venous side of AVF venous outflow, with mixed success, where the juxta-anastomotic vein was found to be of adequate size (3–3.5 mm diameter and 15-20 mm length) to be able to accommodate these DES. (Abstract presented at 16th Annual ASDIN Scientific Meeting, February 21-23, 2020, in Las Vegas, NV).

Coil embolization of competing collateral vessels as a salvage treatment for non-functioning autologous AVFs is a viable treatment option in the majority of patients.[8] Angioplasty and coil embolization are successful and safe procedures that can convert a non-mature fistula into a mature one in more than 80% of patients. Accessory vein embolization may be more important than collateral vein embolization in the presence of stenosis.[9]

Sometimes, high-flow access may cause heart failure, aneurysm or cephalic arch stenosis (CAS). A low urea reduction ratio in an otherwise "well-functioning access" is a simple measurement to determine if an access has pathologically high flow. Clinically asymptomatic central and peripheral venous stenosis can become symptomatic when high flow is generated in the circulation due to AVF. The symptoms of HD vascular access patients associated with non-correctable central venous lesions can resolve successfully and their access is maintained using a precision inflow banding procedure called Minimally Invasive Limited Ligation Endoluminal Assisted Revision (MILLER), as shown by Miller et al.[10],[11] A braided cobalt-chromium external support is also feasible, safe, and effective for flow reduction in high-flow AVF patients.[12]

The AVF embolization is also performed to close the AVF in patients presenting with arm oedema due to chronic central vein occlusion not amenable to any intervention. This has been described in the article in the current issue of the journal, where the authors have used amplatzer vascular plug for embolization as well as flow reduction, though techniques for embolization also include coils, detachable and occluding balloons, and liquid embolic agents, such as n-Butyl cyanoacrylate (NBCA) and ethyl-vinyl alcohol. When no lesions within the vein are visualized, then the cause of fistula failure may be arterial stenosis. Angioplasty may be safely performed on the brachial artery to a primary patency rate of 83% at 1 year and 74% at 2 years.[13]

Central venous stenosis can be tackled with angioplasty with plain balloons or drug-eluting balloons and if there is recurrence of lesion, covered stent can be used. Another endovascular intervention is the balloon-assisted disruption of catheter-related fibrin sheath for dysfunctional tunneled cuff HD catheters. Catheter-related atrial clot (CRAT) can be tackled with thrombolysis, and if adherent to atrial wall, either surgically or with endovascular AngioVac® suction thrombectomy device. An exciting area in endovascular procedures is the creation of AVF. There are two available systems, and they hold good future for HD patients. The Ellipsys® endovascular arteriovenous fistula (endoAVF) system and the WavelinQ endoAVF® system.


  Conclusion Top


Intervention nephrology is an emerging subspecialty of nephrology, which provides an opportunity to nephrologists to undergo training in this area to develop the procedural skills to perform interventions to optimize the care of their patients. Nephrology fellowship programs must take the initiative to promote the development of such skills. Interventional nephrology can be viewed as a refined and resurrected combination of several procedures, which has brought the nephrologist from the periphery to the center.



 
  References Top

1.
Maya I, Asif A. The scope of diagnostic and interventional nephrology. Adv Chronic Kidney Dis 2009;16:299-301.  Back to cited text no. 1
    
2.
Beathard GA, Urbanes A, Litchfield T. Changes in the profile of endovascular procedures performed in freestanding dialysis access centers over 15 years. Clin J Am Soc Nephrol 2017;12:779-86.  Back to cited text no. 2
    
3.
Lok CE, Huber TS, Lee T, Shenoy S, Yevzlin AS, Abreo K, et al. KDOQI clinical practice guideline for vascular access: 2019 update. Am J Kidney Dis 2020;75 (4 Suppl 2):S1-164.  Back to cited text no. 3
    
4.
Allon M, Lok CE. Dialysis fistula or graft: The role for randomized clinical trials. Clin J Am Soc Nephrol 2010;5 2348-54.  Back to cited text no. 4
    
5.
Beathard GA, Arnold P, Jackson J, Litchfield T; Physician Operators Forum of RMS Lifeline. Aggressive treatment of early fistula failure. Kidney Int 2003;64:1487-94.  Back to cited text no. 5
    
6.
Kim SJ, Masaki T, Leypoldt JK, Kamerath CD, Mohammad SF, Cheung AK. Arterial and venous smooth-muscle cells differ in their responses to antiproliferative drugs. J Lab Clin Med 2004;144:156-62.  Back to cited text no. 6
    
7.
Bavare CS, Street TK, Peden EK, Davies MG, Naoum JJ. Stent grafts can convert unusable upper arm arteriovenous fistulas into a functioning hemodialysis access: A retrospective case series. Front Surg 2017;4:13.  Back to cited text no. 7
    
8.
Ahmed O, Patel M, Ginsburg M, Jilani D, Funaki B. Effectiveness of collateral vein embolization for salvage of immature native arteriovenous fistulas. J Vasc Interv Radiol 2014;25:1890-4.  Back to cited text no. 8
    
9.
Nauta L, Voorzaat BM, Rotmans JI, Ghariq E, Urlings T, Bogt KE, et al. Endovascular salvage of non-maturing autogenous arteriovenous fistulas by using angioplasty and competitive vein embolization. J Vasc Access 2020;21:615-22.  Back to cited text no. 9
    
10.
Goel N, Miller GA, Jotwani MC, Licht J, Schur I, Arnold WP. Minimally invasive limited ligation endoluminal-assisted revision (MILLER) for treatment of dialysis access-associated steal syndrome. Kidney Int 2006;70:765-70.  Back to cited text no. 10
    
11.
Miller GA, Friedman A, Khariton A, Preddie DC, Savransky Y. Access flow reduction and recurrent symptomatic cephalic arch stenosis in brachiocephalic hemodialysis arteriovenous fistulas. J Vasc Access 2010;11:281-7.  Back to cited text no. 11
    
12.
Matoussevitch V, Kalmykov E, Brunkwall J. AVA 2. A New Technique to Repair High-Flow Arteriovenous Fistula Using a Novel External Support device. (Abstract Only). J Vasc Surg 2019;70(5):E174.  Back to cited text no. 12
    
13.
Bak Y, Cooper JH, Chang KL. Endovascular therapies for hemodialysis access: Case presentations of salvage, surgical maturation, and maintenance. Vasc Dis Manag 2014;11:E145-55.  Back to cited text no. 13
    
14.
Beathard GA, Lok CE, Glickman MH, Al-Jaishi AA, Bednarski D, Cull DL, et al. Definitions and end points for interventional studies for arteriovenous dialysis access. Clin J Am Soc Nephrol 2018;13:501-12.  Back to cited text no. 14
    



 
 
    Tables

  [Table 1]



 

Top
Print this article  Email this article
 

    

Indian Journal of Nephrology
Published by Wolters Kluwer - Medknow
Online since 20th Sept '07