Established and new concepts to create a stable acces for chronic hemodialysis

Holger Staab, MD University Hospital Leipzig, Germany Clinic for Vascular

Disclosure

Speaker name: Holger Staab I have the following potential conflicts of interest to report: Consulting Employment in industry Stockholder of a healthcare company Owner of a healthcare company Other(s)

X I do not have any potential conflict of interest Nephrologists aim: stable and easy Hämodialysis 3-4 hours 3 X/week

3 Need for a stable Access

4 Average flow of CVC and AV- Minimal required flow for effective hämodialysis 250-300ml/min • Central venous catheters (CVC): • Type of Catheter: Volume of 250-500ml/min • Shaldon • Demers • Hickman • Arteriovenous Fistulas : • AV-Fistel forearm 250ml/min • AV-Fistel upper arm 300-400 ml/min • Prosthetic shunt 400-600 ml/min 5 Standard Vascular Access Options 3-Yr Mortality1 Infection rate2 Reoperation rate2 Annual cost2 Infection Sepsis Central Venous 80% 1.45 2.82 0.86 $90k Catheter

AV Graft 30% 0.39 0.61 1.10 $79k

Surgical 20% 0.18 0.52 0.47 AV $64k

AV fistulas are the preferred method of vascular access

1.Woo K., et al. Influence of Vascular Access Type on Sex and Ethnicity-Related Mortality in Hemodialysis-Dependent Patients. Perm J 2012 Spring;16(2):4-9. Mortality is reported at 3 years. 2.USRDS Annual Report 2011 (2007 data). Reoperation rate includes only angioplasty for AVF and AVG, and CVC replacement for CVC. Complication rates are reported per patient-year. Complication rates are calculated as the number of events (from Medicare claims) divided by the time at risk, which is censored at death, change in modality, change in payment status, or the placement of a different type of access. 6

Tunneled central venous catheters Classical Access Surgery

• Fistula first Movement • „Safe the “

• Minimal anatomical requirements for AV fistulas: – Ultrasound: – Cephalic fore arm >2,5- 3 mm upper arm > 4 mm – Basilic vein >5 mm – Radial > 1,5 mm – Ulnar artery > 1,5 mm – Brachial artery > 3 mm

9

Fore arm AV-fistulas Brescia-Cimino-fistula

Arteria side to vein end anastomis of cephalic vein and distal radial artery – Golden-standard

10 Upper arm AV-fistulae • Cephalic-brachial-fistula: End-vein side arterial–anastomosis with cephalic vein und brachial artery – Good patency – High patients comfort

• Basilic-brachialis-fistula: End-vein-side arterial-anastomosis between basilic vein and brachial artery – Discomfort for patient while dialysis – Often need for second operation to transpose the vein

• Gracz-fistula: End-vein side arterial anastomosis with perforator vein to basilic vein and cephalic vein and either brachial, radial or ulnar artery – Puncture area cephalic and basilic vein – Less risk of inducing HAIDI – Best patency (Vgl. Gracz, Konner) 11 Cephalic-brachial-fistula:

Gracz-fistula: Prosthetic Loop Shunt

• Forearm loop , straight prosthetic graft, axillo- axillary grafts in case of minor quality veins – 6mm PTFE-prosthesis usually first puncture within 14d – High risc of infection twice as high as native fistula – Patency worse compared to native arteriovenous fistula

13 Concept of early canulating prosthetic grafts

Patency comparable to standard prosthetic grafts Hybrid Graft

HeRO Graft Arterial Graft Component has a 6mm inner diameter (ID), 7.4mm outer diameter (OD), and is 53cm long, inclusive of the connector. It consists of an ePTFE hemodialysis graft

HeRO Graft Venous Outflow Component has a 5mm ID, 19F (6.3mm) OD, and is 40cm long. It consists of radiopaque silicone with braided nitinol reinforcement Hybrid Graft Limitations of Surgical AV Fistulas

Clinical Outcomes

Primary failure rate2-5,8 20-60%

Mean maturation time1 4-9 months

Average re-interventions1,7 2-3

Occlusions (thrombosis)6 17-25%

Need for an improved method of AV fistula creation

1 Kimball, et al. Efficiency of the kidney disease outcomes quality initiative guidelines for preemptive vascular access in an academic setting. Journal of Vascular Surgery. Vol 54, No 3. 2011 2 Peterson W., et al. Disparities in Fistula Maturation Persist Despite Preoperative Vascular Mapping. Clin J Am Soc Nephrol. 2008 March; 3(2):437-441 3 Lee, T. et al. Tunneled Catheters in Hemodialysis Patients: Reasons and Subsequent Outcomes. American Journal of Kidney Diseases, Vol 46, No 3 (September), 2005: pp. 501-508 4 Biuckians A, Scott EC, Meier GH, et al. The natural history of autologous fistulas as first-time dialysis access in the KDOQI era. J Vasc Surg 2008; 47:415–421 5 Dember LM, Beck GJ, Allon M, et al. Effect of clopidogrel on early failure of arteriovenous fistulas for hemodialysis: a randomized controlled trial. JAMA 2008; 299:2164–2171 6 Stolic R. Most Important Chronic Complications of Arteriovenous Fistulas for Hemodialysis. Med Princ Pract. 2012 7. Falk, A.M. Maintenance and Salvage of Arteriovenous Fistulas. J Vasc Interv Radiol 2006; 17:807–813.

17 Penetrating trauma occasionally results in AV fistula formation

Diagnosis and management of acute traumatic arteriovenous fistula Kamal Nagpal, MS MRCS,1 Kamran Ahmed, MRCS,1 and RJ Cuschieri, FRCS2, Int J Angiol. 2008 Winter; 17(4): 214–216. 18 TVA everlinQ Endovascular AVF Potential Advantages

Percutaneous AVF creation

Consistent hemodynamic anastomosis No vessel trauma, torque or tension

No surgical anastomosis / Side-to- Side

Enables smaller vessel AVFs

No implant at anastomosis level

19 TVA everlinQ System

Venous catheter

Arterial catheter RF Generator

Radiofrequency electrode creates fistula

6 Fr over the wire Flexible spacers and RX system Magnets align catheters

20 everlinQ procedure

• Ultrasound based puncture of brachial artery and brachial vein and angiography and phlebography

21 everlinQ procedure

22 everlinQ procedure • Transarterial angiography

23 Advantage of percutaneus technique • No scar • Early dilatation of basilic and cephalic vein

24 Clinical Experience: FLEX Study Study Overview Patient Demographics+

Single center, prospective design Gender male 61% Age (years) 51.0+11.4 Paraguay BMI 24.3+3.8 33 patients, 4 cohorts BMI > 25 30.3% Race 6 month follow-up Hispanic 100% Predialysis at enrollment 6.1% Study endpoints: Previous AVF 12.1% • Technical success Diabetes 58% • Patency • Safety Study completed Q1 2014

+ n=33 Rajan DK, et al. J Vasc Interv Radiol 2015; 26:484–490.

25 Clinical Results: FLEX Study

100% 97% 96% 96% Clinical Endpoint FLEX Study 90% Result 80% AVF maturation time 58 days

70% Interventions/patient-year 0.15**

60% Thrombosis 4% (1/26)

50% Stenosis 0%

40% Access infection/patient-year 0%

30% Serious device-related 3% (1/33)* 20% adverse events

10%

0% Technical AVF patency Usable for success @ 24 @6 months+ dialysis hrs

+ 1 patient developed venous hypertension at 37 days from a central vein stenosis. Patient received balloon angioplasty. EndoAVF occluded at 106 days. *1 patient developed pseudoaneurysm during procedure due to arm motion from neuromuscular stimulation. Pseudoaneurysm was resolved with thrombin injection. A procedure modification to limit arm motion mitigated this risk in subsequent cases. ** Interventions for Groups C & D (coil embolization performed at index procedure). 1 intervention in 14 patients, median follow-up time 177 days. Rate reported per patient-year. 26 Novel Endovascular Access Trial (NEAT)

• Multicenter, single arm, prospective design: CA, AU, NZ • 80 patients with 12 months follow-up • Primary endpoint: – Fistula Usability @ 3mo • Secondary endpoints: – Procedural success – Safety – Re-intervention rate – Primary & secondary patency – Others

27 Summary • CVC should possibly be avoided as long term access • Golden standard access is a arteriovenous fistula preferable in fore arm position • Prosthetic grafts are an option for older patients with a minor vein quality • Early canulation prosthetic grafts might reduce the quantity of CVC • Hybrid grafts can be used for complicated end stage cases • Endovascular techniques for creating av access expand the spectrum of AV fistula surgery • Patients with no option for a fore arm fistula can be considered • Endovascular AV-fistula do not prevent further surgical options 28 Thank you for your attention!

© Universitätsklinikum Leipzig 29 AöR Established and new concepts to create a stable acces for chronic hemodialysis

Holger Staab, MD University Hospital Leipzig, Germany Clinic for Vascular Surgery