Bilateral HeRO Grafts

52 year old Male on dialysis. What are the devices? • Xray of the Week

Figure 2: Frontal chest radiograph in a dialysis patient. What are the devices?

Figure 2: Frontal chest radiograph in a dialysis patient with bilateral HeRO grafts. The green arrow indicates the proximal aspect of the right-sided nitinol-reinforced venous component entering the central circulation via the internal jugular vein. The red arrow highlights the left-sided system entering via the subclavian vein. The yellow arrow identifies the convergence of the dual mesh-like tubes as they cross the cavoatrial junction.

Radiologic Evaluation and Management of Bilateral HeRO Grafts in Access-Challenged Patients

Discussion

The clinical course of patients with end-stage kidney disease (ESKD) is often limited by "vascular access exhaustion." Central venous stenosis (CVS) or occlusion (CVO) occurs in up to 40% of patients who have had prior central venous catheters, leading to venous hypertension and the failure of standard arteriovenous fistulas or grafts. For these access-challenged patients, the Hemodialysis Reliable Outflow (HeRO) graft provides a critical salvage option by bypassing central obstructions to drain blood directly into the right atrium.  

System Components and Radiographic Appearance

The HeRO system is a hybrid device consisting of three subcutaneous parts that a general radiologist must recognize on routine imaging:

1. Arterial Graft Component: A 6-mm inner diameter expanded polytetrafluoroethylene (ePTFE) graft. On radiographs, it is poorly radiopaque, but it features distinctive PTFE beading near its distal end to provide kink resistance.  

2. Titanium Connector: This is a highly radiopaque, tapered junctional device typically located in the deltopectoral groove. It joins the arterial graft to the venous outflow component.  

3. Venous Outflow Component (VOC): This is a 19-French radiopaque silicone tube reinforced with a 48-braid nitinol mesh. It produces a dense, mesh-like "necklace" appearance on chest radiographs, which is the hallmark of the device.  

Imaging Findings

In the provided frontal chest radiograph, a rare bilateral HeRO graft configuration is visualized. This setup is typically reserved for patients with total, bilateral central venous occlusions who have exhausted all other upper-extremity options.  

The green arrow identifies the right-sided system, where the reinforced nitinol component enters the central circulation, typically via the right internal jugular vein. The red arrow points to the contralateral left-sided system entering via the subclavian vein. Left-sided placement is technically more complex due to the tortuous course of the left brachiocephalic vein. The yellow arrow points to the central convergence of the two nitinol-reinforced components at the cavoatrial junction. The distal tips of these components should ideally reside in the mid-to-upper right atrium to ensure optimal flow and minimize the risk of thrombus formation.  

While radiographs are used for routine surveillance, contrast-enhanced CT venography (CTV) or ferumoxytol-enhanced MR venography (MRV) is the gold standard for preoperative mapping of occlusions and collateral pathways. Ultrasound is primarily used to evaluate the superficial arterial graft segment for patency and volume flow.  

Differential Diagnosis

Radiologists must differentiate the HeRO system from other common thoracic devices:

• Standard Tunneled Dialysis Catheters (TDCs): These are non-reinforced, less radiopaque, and lack the titanium connector and nitinol mesh "necklace" appearance.  

• Central Venous Stents: While mesh-like, stents are entirely intravascular and are not connected to a subcutaneous arterial graft.  

• Pacemaker and AICD Leads: These are much thinner and terminate in specific cardiac chambers (e.g., right ventricular apex). They do not feature the wide-caliber mesh seen in HeRO components.  

Management and Prognosis

The HeRO graft offers a major clinical advantage over standard catheters by being entirely subcutaneous, which reduces the risk of bacteremia by approximately 69%. Patency rates are comparable to conventional ePTFE grafts, with secondary patency—the ability to maintain function through interventions—reported at 80% to 90% at one year.  

However, the device requires frequent maintenance. On average, patients require 1.5 to 2.2 radiologic interventions per year to treat complications such as graft thrombosis or component migration. Migration of the nitinol component (either retracting into the SVC or advancing into the IVC) is a serious complication that can lead to device dysfunction or atrial injury.  

Key Learning Points

• Recognition: Identify the HeRO graft by its dense nitinol-braid "necklace" appearance and the highly radiopaque titanium connector in the deltopectoral groove.  

• Bilateral Configuration: Bilateral grafts represent a salvage strategy for patients with total thoracic central vein obstruction (TCVO).  

• Clinical Value: The subcutaneous design significantly lowers infection rates compared to tunneled catheters.  

• Radiologist's Role: General radiologists are often the first to identify device complications like kinking at the connector or tip migration on routine chest films.  

• Advanced Imaging: Ferumoxytol-enhanced MRV is a safe alternative for venous mapping in patients with severe renal impairment.  

References:

1. Katzman HE, McLafferty RB, Ross JR, Glickman MH, Peden EK, Lawson JH. Initial experience and outcome of a new hemodialysis access device for catheter-dependent patients. J Vasc Surg. 2009;50(3):600-607. doi:10.1016/j.jvs.2009.04.014. https://pubmed.ncbi.nlm.nih.gov/19628360/

2. Tabriz DM, Arslan B. HeRO Graft: Indications, Technique, Outcomes, and Secondary Intervention. Semin Intervent Radiol. 2022;39(1):82-89. doi:10.1055/s-0042-1742391. https://pubmed.ncbi.nlm.nih.gov/35210737/

3. Fitzgerald KM, Newell KR, Shin DS, et al. Thoracic Central Vein Obstruction: Endovascular Recanalization and Reconstruction. RadioGraphics. 2024;44(1):e240178. doi:10.1148/rg.240178. https://pubmed.ncbi.nlm.nih.gov/38161555/

4. Gage SM, Katzman HE, Ross JR, et al. Multi-center experience of 164 consecutive Hemodialysis Reliable Outflow graft implants for hemodialysis treatment. Eur J Vasc Endovasc Surg. 2012;44(1):93-99. doi:10.1016/j.ejvs.2012.04.011. https://pubmed.ncbi.nlm.nih.gov/22538166/

5. Griffin AS, Gage SM, Lawson JH, Kim CY. Early infection risk with primary versus staged Hemodialysis Reliable Outflow (HeRO) graft implantation. J Vasc Surg. 2017;65(1):136-141. doi:10.1016/j.jvs.2016.08.083. https://pubmed.ncbi.nlm.nih.gov/27751737/

6. Kim Y, Cui CL, Eze AN, et al. Perioperative and long-term outcomes after Hemodialysis Reliable Outflow (HeRO) graft surgery. J Vasc Surg. 2024;82(6):1458-1466. doi:10.1016/j.jvs.2024.01.002. https://pubmed.ncbi.nlm.nih.gov/38311003/

7. Gebhard TA, Bryant JA, Adam Grezaffi J, et al. Percutaneous interventions on the hemodialysis reliable outflow vascular access device. J Vasc Interv Radiol. 2013;24(4):543-549. doi:10.1016/j.jvir.2012.12.027. https://pubmed.ncbi.nlm.nih.gov/23453715/

8. Cline BC, Gish PE, Kim CY. Hemodialysis Reliable Outflow (HeRO) graft creation in upper extremities abandoned due to stent obstruction via recanalization and HeRO outflow component insertion across stent interstices. J Vasc Access. 2023;24(5):1017-1022. doi:10.1177/11297298211065799. https://pubmed.ncbi.nlm.nih.gov/34889146/

9. Nguyen K, Shin DS, Monroe EJ, et al. Ferumoxytol-enhanced MR Venography of the Central Veins of the Thorax for the Evaluation of Stenosis and Occlusion in Patients with Renal Impairment. Radiol Cardiothorac Imaging. 2020;2(6):e200339. doi:10.1148/ryct.2020200339. https://pubmed.ncbi.nlm.nih.gov/33392497/

10. Medjahed K, et al. Point-of-Care Ultrasound (POCUS) Diagnosis of Pulmonary Embolism in a Patient With a HeRO Graft. Cureus. 2025;17(11):e96273. doi:10.7759/cureus.96273. https://pubmed.ncbi.nlm.nih.gov/39564887/

11. Kilari S, Takahashi E, Misra S. Current and Evolving Therapies for Arteriovenous Fistula and Graft Dysfunction. Kidney360. 2021;2(12):2021-2032. doi:10.34067/KID.0004552021. https://pubmed.ncbi.nlm.nih.gov/35373105/

12. Lok CE, Huber TS, Lee T, et al. KDOQI Clinical Practice Guideline for Vascular Access: 2019 Update. Am J Kidney Dis. 2020;75(4 Suppl 2):S1-S164. doi:10.1053/j.ajkd.2019.12.001. https://pubmed.ncbi.nlm.nih.gov/32778223/

13. Ekanem AA, Eze A, Eze AN, Southerland KW. A rare case of hemorrhage from spontaneous disconnection of super-HeRO adapter and early-cannulation graft: A case report. J Vasc Access. 2024;25(6):1865-1868. doi:10.1177/11297298231154563. https://pubmed.ncbi.nlm.nih.gov/36785462/

Kevin M. Rice, MD is the president of Global Radiology CME and is a radiologist with Cape Radiology Group. He has held several leadership positions including Board Member and Chief of Staff at Valley Presbyterian Hospital in Los Angeles, California. Dr. Rice has made several media appearances as part of his ongoing commitment to public education. Dr. Rice's passion for state-of-the-art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015, Dr. Rice and Natalie Rice founded Global Radiology CME to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. In 2016, Dr. Rice was nominated and became a semifinalist for a "Minnie" Award for the Most Effective Radiology Educator. He was once again a semifinalist for a "Minnie" for 2021's Most Effective Radiology Educator by AuntMinnie.com. He has continued to teach by mentoring medical students interested in radiology. Everyone he has mentored has been accepted into top programs across the country, including Harvard, UC San Diego, Northwestern, Vanderbilt, and Thomas Jefferson.

Follow Dr. Rice on Twitter @KevinRiceMD 

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