A thumbnail sketch of haemodialysis access: Past, present, and future in the USA

Bart Dolmatch gives an overview of the history of haemodialysis access in the USA, and balances the pros and cons of current access options. He outlines his hopes for the increasing role he believes interventional radiologists should play in the management of end-stage renal disease patients, and how innovation is helping physicians achieve better clinical results.

While the incidence of end-stage renal disease (ESRD) in the USA has reached a plateau over the past few years, prevalence continues to climb due to lower mortality rates.¹ ESRD is treated with renal replacement, but it is costly and places a growing financial burden upon Medicare participants. Medicare-paid claims for ESRD, including renal replacement, represented over 7% of all Medicare payments and exceeded US$35 billion in 2015–2016.²

Renal replacement can be performed with a kidney transplantation, peritoneal dialysis, or haemodialysis. For many people, transplantation may be the best option, but due to the ongoing shortage of donor organs, fewer than 3% of people with ESRD received a pre-emptive transplant. Peritoneal dialysis, conveniently performed at home by most people, accounted for only 9.7% of all renal replacement. Haemodialysis accounted for renal replacement for nearly 90% of the ESRD population in the USA.¹

Haemodialysis is simply the process of cycling a person’s blood through a filtration system, removing toxins while balancing fluids and electrolytes, and returning the blood back to the patient’s circulatory system. Efficient cycling of blood requires a way to both remove and replace blood, typically through one of three methods: a dual lumen catheter; an arteriovenous graft (AVG); or an arteriovenous fistula (AVF). An AVG is a surgically inter-posed conduit between an artery and vein that is accessed for haemodialysis. An AVF is the direct connection of an artery to vein, where the venous side of the circuit serves as the access site. Both an AVG and AVF are accessed for haemodialysis using two-needle cannulation—one for cycling blood to the dialyser, the other to return blood to the patient.

All three types of vascular access have pros and cons. Catheters are convenient but have the highest morbidity rates compared to AVGs and AVFs.^3,4 AVGs had a high rate of usability, but up to 75% failed in their first year.⁵ Once an AVF is ready for repeated successful haemodialysis, it is often an excellent long-term vascular access solution with better durability than an AVG. However up to 60% of AVFs were not ready for use within four to five months after surgery, and many were abandoned before any attempt to salvage.⁶

While there are problems with all forms of haemodialysis access, the AVF remains the preferred modality and accounts for about two-thirds of haemodialysis access in the USA.⁵ For more than 50 years, creation of an AVF was the purview of surgeons. However, in 2018, two catheter-based systems were cleared for percutaneous AVF creation by the US Food and Drug Administration (FDA)—BD’s WavelinQ and Avenu Medical’s Ellipsys. The hope is that percutaneous AVFs, created without pre-operative delay, will have high rates of early unassisted usability and remain functional. So far, data are encouraging.^6,7

AVGs and AVFs often develop stenoses that reduce dialysis efficiency and can lead to thrombosis. Percutaneous transluminal angioplasty (PTA) has been used for decades, though with varying durability. We have learned that bare metal stents do not improve durability over successful PTA.^8,9,10 However, covered stents from BD such as the Flair, Fluency and Covera, as well as Gore and Associate’s Viabahn, reduce restenosis rates. These covered stents have demonstrated superior outcomes in prospective clinical trials when compared to PTA.^{11,12,13,14,15} In addition, BD’s Lutonix drug-coated balloon also confers improved outcomes compared to PTA.¹⁶

The past few years have seen great strides in creating and maintaining haemodialysis access. We now have new ways to achieve better results, with the hope that through ongoing innovation and comparative prospective clinical research, we can improve the lives of patients with ESRD.

Bart Dolmatch is an interventional radiologist at The Palo Alto Medical Foundation and El Camino Hospital, Palo Alto, USA.

References

1. 2018, United States Renal Data System Annual Report, End-Stage Renal Disease, Chapter 1, https://www.usrds.org/2018/view/v2_01.aspx, accessed 8/15/2019
2. 2018, United States Renal Data System Annual Report, End-Stage Renal Disease, Chapter 9: Healthcare Expenditures for Persons with ESRD, https://www.usrds.org/2018/view/v2_09.aspx Accessed August 15, 2019.
3. Charmaine E Lok and Robert Foley, Vascular Access Morbidity and Mortality: Trends of the Last Decade, CJASN 2013; 8 (7):1213–1219.
4. Gürbey Ocak, et al, Haemodialysis catheters increase mortality as compared to arteriovenous accesses especially in elderly patients Nephrology Dialysis Transplantation, 2011; 26(8):2,611–2,617.
5. 2018 United States Renal Data System Annual Report, End-Stage Renal Disease, Chapter 3: Vascular Access. https://www.usrds.org/2018/view/v2_03.aspx, Accessed August 15, 2019.
6. Charmaine Lok et al, Endovascular Proximal Forearm Arteriovenous Fistula for Hemodialysis Access: Results of the Prospective, Multicenter Novel Endovascular Access Trial (NEAT). American Journal of Kidney Disease, 2017; 70(4):486–497
7. Jeffrey E. Hull, William C. Jennings, Randy I. Cooper, et al. The Pivotal Multicenter Trial of Ultrasound-Guided Percutaneous Arteriovenous Fistula Creation for Hemodialysis Access. J Vasc Interv Radiol. 2018; 29(2):149–158.
8. Quinn S F, Schuman E S, Demlow T A. et al. Percutaneous transluminal angioplasty versus endovascular stent placement in the treatment of venous stenoses in patients undergoing hemodialysis: intermediate results. J Vasc Interv Radiol. 1995;6(6):851–855.
9. Beathard G A. Gianturco self-expanding stent in the treatment of stenosis in dialysis access grafts. Kidney Int. 1993;43(4):872–877.
10. Hoffer E K, Sultan S, Herskowitz M M, Daniels I D, Sclafani S JA. Prospective randomized trial of a metallic intravascular stent in hemodialysis graft maintenance. J Vasc Interv Radiol. 1997;8(6):965–973.
11. Haskal ZJ, Trerotola S, Dolmatch B, Schuman E, et al. Stent Graft versus Balloon Angioplasty for Failing Dialysis-Access Grafts. 2010. N Engl J Med 2010;362:494-503.
12. Haskal ZJ, Saad TF, Hoggard JG, Cooper RI, et al. Prospective, Randomized, Concurrently-Controlled Study of a Stent Graft versus Balloon Angioplasty for Treatment of Arteriovenous Access Graft Stenosis: 2-Year Results of the RENOVA Study. J Vasc Interv Radiol. 2016 Aug;27(8):1105-1114.
13. Falk A, Maya ID, Yevzlin AS, and RESCUE Investigators. A Prospective, Randomized Study of an Expanded Polytetrafluoroethylene Stent Graft versus Balloon Angioplasty for In-Stent Restenosis in Arteriovenous Grafts and Fistulae: Two-Year Results of the RESCUE Study. J Vasc Interv Radiol. 2016; 27(10):1465-1476.
14. Vesely T, DaVanzo W, Behrend T, Dwyer A, Aruny J. Balloon angioplasty versus Viabahn stent graft for treatment of failing or thrombosed prosthetic hemodialysis grafts. J Vasc Surg. 2016 Nov;64(5):1400-1410.
15. Covera Vascular Covered Stent Instructions for Use. Bard Peripheral Vascular. B05872 Rev.3/05-18. https://www.accessdata.fda.gov/cdrh_docs/pdf17/P170042D.pdf Accessed August 15, 2019.
16. Scott O. Trerotola, Jeffrey Lawson, Prabir Roy-Chaudhury and Theodore F. Saad; for the Lutonix AV Clinical Trial Investigators. Drug Coated Balloon Angioplasty in Failing AV Fistulas: A Randomized Controlled Trial, CJASN 2018; 13(8):1215-1224.