RESEARCH ARTICLE


LEARNING FROM IMAGES Size Matters



Tushar J. Vachharajani*, 1 , Arif Asif2
1 Departments of Nephrology, W.G. (Bill) Hefner Veterans Affairs Medical Center, Salisbury, NC, USA
2 Department of Nephrology, Albany Medical College, Albany, NY, USA


Article Metrics

CrossRef Citations:
0
Total Statistics:

Full-Text HTML Views: 654
Abstract HTML Views: 652
PDF Downloads: 168
ePub Downloads: 165
Total Views/Downloads: 1639
Unique Statistics:

Full-Text HTML Views: 413
Abstract HTML Views: 394
PDF Downloads: 126
ePub Downloads: 118
Total Views/Downloads: 1051



© Buffington et al.; Licensee Bentham Open.

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.5/), which permits unrestrictive use, distribution, and reproduction in any medium, provided the original work is properly cited.

* Address correspondence to this author at the Nephrology Service, W. G. (Bill) Hefner Veterans Affairs Medical Center, 1601 Brenner Avenue, Salisbury, NC 28144, USA; Tel: 704-638-9000; Fax: 704-638-3855; E-mail: Tushar.vachharajani@va.gov




Arteriovenous fistula (AVF) is considered the preferred vascular access to provide maintenance hemodialysis for its known lower incidence of morbidity and mortality compared to arteriovenous graft and central venous catheters. Nevertheless, early maturation failure and development of stenosis remain major hurdles leading to AVF dysfunction. Endovascular stent placement is often necessary to treat stenosis that recurs frequently or demonstrates significant elastic recoil despite adequate angioplasty. The decision to place an endovascular stent is complex and involves selecting a suitable candidate and choosing an appropriate stent. The length and luminal diameter of the stent need to be selected very carefully for treating venous stenosis. Unlike arteries, the veins are thin walled, compliant and tend to dilate easily. In the case of central veins, the venous diameter can differ with the variations in intrathoracic pressure related to respiration.

In the case presented in this report, a recurrent outflow stenosis in an upper arm brachiocephalic AVF was treated with two overlapping, inadequately sized bare-metal stents (Fig. 1). A high blood flow in an upper arm AVF combined with non-compliant stented segment of the outflow vein resulted in the development of aneurysmal dilatation distal to the stent. Stent deployment in an AVF and arteriovenous graft (AVG) should preferably be reserved for endovascular emergencies such as vascular tears and in high-risk surgical candidates [1]. Surgical revision is a preferred option whenever possible. Stent deployment should be clearly avoided in the cannulation segment of the AVF [2]. Accidental cannulation of the stent for dialysis can increase the risk of stent rupture with protrusion of the sharp end through the skin and can be a potential hazard to the dialysis staff [3].

Fig. (1).

An upper arm arteriovenous fistula with inadequately sized bare-metal stents in the outflow segment (marked by white arrows) leading to aneurysm (marked by black arrow-heads) formation in the distal segment. The direction of the blood flow is indicated by the red arrow.


CONFLICT OF INTEREST

The authors confirm that this article content has no conflict of interest.

ACKNOWLEDGEMENTS

Declared none.

REFERENCES

[1] Vascular Access 2006 Work Group, Clinical practice guidelines for vascular access. Am J Kidney Dis 2006; 48: S176-247.
[2] Niyyar VD, Moossavi S, Vachharajani TJ. Cannulating the hemodialysis access through a stent graft - is it advisable? Clin Nephrol 2012; 77(5): 409-12.
[3] Asif A, Gadalean F, Eid N, Merrill D, Salman L. Stent graft infection and protrusion through the skin: clinical considerations and potential medico-legal ramifications Semin Dial 2010; 23(5): 540-2.