Fistulogram for a Cephalic Arch Aneurysm

More than 100,000 arteriovenous fistulas (AVFs) are created annually in the United States, but are frequently complicated by venous outflow stenosis, aneurysm formation, and aneurysms that often require angiographic evaluation and intervention. Cephalic arch stenosis is a particularly common cause of dysfunction in brachiocephalic fistulas due to high flow. This is typically managed with fistulogram-guided angioplasty, although repeated interventions are associated with restenosis and access-related complications.

We present the case of a 63-year-old, right-hand dominant male with end-stage renal disease secondary to glomerulonephritis on dialysis through a left upper extremity brachiocephalic AVF that was complicated by recurrent cephalic arch stenosis requiring multiple angioplasties, which ultimately resulted in the development of a cephalic arch aneurysm. Subsequent fistulograms demonstrated a high-grade stenosis that could not be traversed despite multiple attempts.

Comprehensive preoperative evaluation included focused history, physical examination, duplex ultrasound, and computed tomography venography. The fistulogram described in this article demonstrated a patent, high-flow AVF with a saccular aneurysm of the proximal cephalic vein measuring up to 28 mm without thrombus and no hemodynamically significant flow-limiting stenosis. Given the absence of flow limitation and the risk of compromising future access, stent placement was deferred.

This case highlights the importance of individualized decision-making in the management of complex AVF complications. Fistulograms serve as a critical diagnostic and therapeutic tool, allowing real-time assessment of anatomy and flow to guide intervention. In select patients, conservative endovascular management with surveillance may preserve access durability and delay the need for more invasive procedures.

Dialysis access; fistulogram; aneurysm.

Renal replacement therapy (RRT) via arteriovenous fistulas (AVFs) is performed in over 100,000 patients annually in the United States to support long-term hemodialysis as a bridge to potential renal transplantation.¹ Although AVFs remain a preferred form of vascular access, they are frequently complicated by stenosis, aneurysm formation, and aneurysms, many of which require angiographic evaluation and intervention.² Fistulograms plays a central role in both the diagnosis and treatment of access-related complications.

Among the access-related complications, cephalic arch stenosis represents a common and clinically significant cause of AVF dysfunction, occurring in approximately 15% of all fistulas and in up to 39% of brachiocephalic fistulas.³ Lesions at the cephalic arch are routinely evaluated and treated using fistulogram-guided angioplasty; however, repeated balloon dilations are associated with restenosis and access-related complications.^2,4,5 In this article, we describe the preoperative evaluation and demonstrate the technical steps involved in performing a fistulogram for both diagnostic assessment and therapeutic intervention in a patient with a cephalic arch aneurysm.

A detailed history of the fistula creation and a focused physical examination of the access extremity are essential components of the preprocedural evaluation for fistulograms. Key elements include the timing of fistula creation, prior access sites, and details regarding arterial inflow and venous outflow, as these factors influence both diagnostic interpretation and procedural planning.⁵

Dialysis performance should be reviewed. This includes flow rates, adequacy of dialysis, difficulty with cannulation, prolonged bleeding after needle removal, or changes in pump pressures, as these findings may indicate underlying access dysfunction. Symptoms suggestive of access-related complications should also be assessed, including arm swelling, pain, or neurologic symptoms concerning for steal syndrome.⁶

A history of prior access interventions, such as angioplasty, stenting, or surgical revision, is critical to understanding the expected anatomy and likelihood of restenosis. Additionally, comorbid conditions including chronic infection, dermatologic disease at the access site, and immunosuppression should be documented, as these factors may influence procedural approach and risk stratification.

Our patient is a 63-year-old right-hand dominant male with a history of plasma cell disorder treated with chemotherapy, glomerulonephritis, and end-stage renal disease managed with home hemodialysis. He underwent creation of a left upper extremity brachiocephalic fistula in 2021, which was complicated by cephalic arch stenosis requiring venoplasty with dilation to 10 mm in the distal fistula and 8 mm in the cephalic arch and subclavian vein by interventional nephrology at an outside institution. A subsequent fistulogram demonstrated a cephalic arch pseudoaneurysm vs aneurysm with high-grade stenosis that could not be crossed despite two attempts by interventional radiology at an outside institution. The most recent fistulogram, performed by interventional radiology at an outside institution in July 2025, described a persistent cephalic arch pseudoaneurysm vs aneurysm, prompting referral for vascular surgical evaluation.

Physical examination of an AVF should follow a systematic “look, listen, feel” approach, incorporating inspection, palpation, and auscultation to identify clinical indicators of access dysfunction.⁷

Inspection should assess for edema of the access extremity, arm asymmetry, or the presence of venous collaterals along the chest wall, which may suggest central venous obstruction. The skin overlying the AVF should be carefully evaluated for thinning, shininess, hypopigmentation, ulceration, or areas of focal dilation over aneurysmal segments, which may indicate impending rupture. Visible, exaggerated pulsations along the fistula may suggest elevated access pressures due to venous outflow stenosis. Palpation should assess for the presence and quality of a thrill. A continuous, low-resistance thrill is characteristic of a well-functioning fistula, whereas a prominent pulsation or loss of continuous thrill may indicate significant outflow stenosis.⁷ A weak thrill, particularly in a recently created fistula, may suggest anastomotic or arterial inflow stenosis. Auscultation should reveal a continuous, medium-pitched bruit. A high-pitched or discontinuous bruit may indicate focal stenosis or reduced flow.

Examination of the hand distal to the fistula is essential and should include assessment of skin color, temperature, capillary refill, motor function, and sensation to evaluate for adequate distal perfusion. Radial and ulnar pulses should be palpated when possible. Symptoms or signs of ischemia, including pain, numbness, weakness, or coolness, should raise concern for dialysis access–associated steal syndrome.

In our case, physical examination demonstrated no visible arm edema, though venous collaterals were noted along the chest wall. There was no hypopigmentation or skin breakdown over the well-developed fistula. On palpation, increased pulsatility was appreciated distal to the buttonhole access sites, with preservation of a continuous thrill. Auscultation revealed a high-pitched, whistling bruit proximal to the access site, concerning for venous stenosis.

Duplex ultrasound is recommended as the initial imaging modality prior to a fistulogram. Evaluation of a AVF follows a systematic protocol assessing the afferent artery, the anastomosis, and the entire venous outflow system.⁸

For detection of clinically significant stenosis, a peak systolic velocity (PSV) ratio ≥ 2.0 at the site of narrowing compared with the immediately upstream segment has an approximately 80% positive predictive value.⁹ Assessment of the brachial artery is particularly important for identifying access-related complications. Findings that should prompt further evaluation for stenosis or thrombosis include a brachial artery diameter ≤ 5.4 mm, volume flow ≤ 460 mL/min, pulsatility index > 1.04, or resistance index > 0.60. For percutaneous arteriovenous fistulas, a brachial artery volumetric flow of approximately 800–1,000 mL/min is considered optimal.
A duplex ultrasound in this case showed a patent left upper extremity brachiocephalic arteriovenous fistula with high-volume flow, measuring 3,037–4,330 mL/min across the access circuit. Peak systolic velocities were elevated at the proximal anastomosis (369 cm/s) but without a significant velocity step-up or downstream narrowing. Inflow arterial velocities remained within acceptable ranges (brachial artery 181–254 cm/s). Venous outflow was widely patent, with cephalic vein diameters of 11.5–15.4 mm. Duplex did not demonstrate evidence of hemodynamically significant inflow or outflow stenosis.

Additional imaging modalities, including computed tomography venogram (CTV), may be useful in selected cases to better assess the central vasculature. In this patient, a CTV was obtained to further characterize the cephalic arch aneurysm in terms of size, morphology, and surrounding anatomy prior to intervention. This patient had a large saccular pseudoaneurysm vs aneurysm arising from the left proximal cephalic vein measuring 20 x 28 mm without intraluminal or mural thrombus, which was a smaller diameter than previously measured by fistulogram performed by interventional radiology at an outside hospital. Vascular radiology was unable to definitively determine whether this represented a pseudoaneurysm or a true aneurysm.

Natural History
Venous outflow stenosis in AVF is a progressive condition resulting from neointimal hyperplasia. Approximately 40% of AVFs require intervention within one year for venous outflow stenosis.¹⁰ Stenotic lesions tend to develop at predictable anatomic sites, most commonly within the cephalic arch. When left untreated, venous stenosis invariably precedes thrombosis, with an underlying anatomic defect identified in nearly all thrombosed AVFs.¹¹

In this case, treatment of cephalic arch stenosis was complicated by the development of an aneurysm. While aneurysm formation at cannulation sites is well described in the literature,¹² aneurysms involving treated central venous segments such as the cephalic arch are uncommon and less well characterized.

Two commonly employed treatments for venous outflow stenosis include percutaneous transluminal angioplasty (PTA) and stent placement. PTA is frequently employed as the initial intervention for venous outflow stenosis, supported by a pooled cohort of 2,166 cases across 15 studies demonstrating a primary patency rate of 62% and cumulative patency of 85% at six months.¹⁰ Stent placement may be considered for more aggressive or recurrent stenotic lesions; however, available data are limited. In one small study, no significant difference in one-year primary patency was observed between lesions treated with primary angioplasty versus bare-metal stent placement.⁴ In another small prospective study of covered stents compared to PTA, the covered stent group showed 28.4% improved target lesion primary patency and fewer reinterventions at one year.¹³

Covered stents may also be used in the treatment of select aneurysms; however, careful attention must be paid to stent positioning. Placement posterior to the first rib should be avoided due to the risk of stent compression. Distal outflow veins should not be jailed by the covered stent, as this may compromise future endovascular or surgical treatment options. Aneurysms may also be treated with coil embolization, although this approach is not well studied in the context of AVFs.

In select cases, open surgical reconstruction, including aneurysmorrhaphy, may be considered;¹⁴ however, these procedures carry substantial morbidity due to the anatomic location of the lesions. Surgical bypass often requires clavicular resection or sternotomy, exposing patients to increased operative risk and prolonged recovery.

The primary goal of treatment was to evaluate the severity of central venous stenosis and determine the morphology of the cephalic arch aneurysm for potential intervention. Fistulograms provide a comprehensive diagnostic and therapeutic platform, allowing real-time assessment of access anatomy, flow characteristics, and lesion severity. Based on intraoperative findings, such as the presence of a flow-limiting stenosis, interval enlargement of the aneurysm, or identification of a pseudoaneurysm, the appropriate treatment strategy could then be selected.

In patients with a history of repeated access-related complications, careful consideration should be given to the choice of access site on the AVF. When a stenotic segment is suspected, accessing the fistula past the lesion is often prudent to facilitate diagnostic evaluation and potential intervention. If the anastomosis is stenotic, access more proximally and treating retrograde is always possible.

Patients who are candidates for kidney transplantation, particularly those who may be high on the transplant waitlist, may warrant a more conservative interventional strategy, as arteriovenous fistulas serve as a temporary bridge to transplantation.

Fistulograms are commonly performed for AVFs that demonstrate clinical dysfunction during dialysis or abnormal findings on duplex ultrasound evaluation. As the preferred vascular access for RRT in patients with suitable anatomy and longer expected lifespans, AVFs offer superior long-term outcomes compared with catheters or grafts; however, they are frequently complicated by stenosis, aneurysm formation, and aneurysms that require endovascular evaluation and intervention.¹⁵ Among these complications, cephalic arch stenosis is a particularly common cause of AVF dysfunction in brachiocephalic fistulas, typically managed with fistulogram-guided angioplasty.⁹ Despite high technical success rates, repeated interventions are frequently required due to restenosis and access-related complications.

In this case, we describe a 63-year-old male with end-stage renal disease secondary to glomerulonephritis who underwent creation of a left upper extremity brachiocephalic fistula complicated by recurrent cephalic arch stenosis. Multiple prior angioplasties resulted in the development of a cephalic arch pseudoaneurysm vs aneurysm. Subsequent endovascular evaluation demonstrated a high-grade stenosis that could not be crossed despite multiple attempts. On repeat fistulogram seen in this video, the abnormality was characterized as an aneurysm that measured a maximum diameter of 2 cm, which was smaller than previously reported, and the associated stenosis was not flow limiting. In light of these findings, definitive intervention was deferred. The anatomic constraint imposed by the first rib raised concern for stent compression, and stent placement at that time would have risked compromising future access options and precipitating fistula failure. Importantly, a retrograde DSA performed by injecting contrast through the sheath while applying compression proximal to the fistula demonstrated patent and brisk distal outflow. The patient was discharged the same day and demonstrated clinical stability on follow-up, with plans for interval imaging to monitor aneurysm progression.

Central venous stenosis is most commonly attributed to prior central venous catheterization, particularly involving the subclavian vein, where endothelial injury predisposes to neointimal hyperplasia and luminal narrowing.¹⁶ A second contributing factor is the high-flow state created by an arteriovenous shunt, which can generate turbulent flow and abnormal shear stress, promoting progressive venous remodeling.¹⁷ Notably, in this case, the patient did not have a history of temporary dialysis catheter placement, suggesting that high-flow hemodynamics likely played a primary role in the development of cephalic arch pathology.

Historically, management of central venous stenosis relied on open surgical reconstruction, which carries substantial morbidity due to the anatomic location of these lesions. Older open surgical options for bypass have required clavicular resection or sternotomy, exposing patients to increased operative risk and prolonged recovery.¹⁸ Although surgical series have reported primary patency rates approaching 80% at one year, these procedures are now generally reserved for select low-risk patients with exhausted endovascular options. Contemporary open procedures include cephalic vein transposition (CVT), which does not require clavicle resection or sternotomy and redirects venous outflow into a lower-resistance central vein, thereby bypassing the stenotic cephalic arch. One study demonstrated that CVT achieved primary-assisted patency rates of 100% and 87.5% at 6 and 12 months, respectively, compared with 68.2% and 57.3% for PTA.¹⁹ In cases of recurrent stenosis or severe venous hypertension refractory to intervention, fistula ligation with alternative access creation may be required.⁵

With advances in endovascular techniques, PTA has become the standard initial treatment for central venous stenosis. However, the role of stenting remains nuanced. While some studies have demonstrated no significant difference in long-term patency between angioplasty and stenting,⁴ others suggest that stents may offer modest improvements in central venous stenosis by reducing elastic recoil, excluding injured intima, and providing structural support in highly compliant central veins.^20,21 These benefits appear most pronounced in lesions with marked recoil or early restenosis following angioplasty alone. Nevertheless, primary patency rates remain limited, and most patients require repeat interventions to maintain long-term access function.²² Importantly, stent placement may restrict future treatment options and must therefore be carefully considered in younger patients or those awaiting renal transplantation.

Alternative dialysis modalities, including peritoneal dialysis, represent additional options for selected patients. Population-level studies have demonstrated comparable survival outcomes between peritoneal dialysis and hemodialysis, particularly in the early years following dialysis initiation.²³ In this case, peritoneal dialysis was not a viable option due to the patient’s history of plasma cell disorder and prior chemotherapy, underscoring the need to preserve functional vascular access whenever possible.

This case highlights the importance of individualized decision-making in the management of complex AVF complications. Advances in endovascular technology have expanded therapeutic options, allowing clinicians to balance lesion severity, access longevity, and patient-specific factors when determining the optimal intervention. In select cases, deferring aggressive treatment in favor of surveillance and flow optimization may preserve access function and delay the need for more invasive procedures. As the population of patients with end-stage renal disease continues to grow, thoughtful application of evolving endovascular strategies remains essential to optimizing outcomes while minimizing morbidity.

• Standard minor vascular instrument tray with sterile draping and electrocautery.
• Ultrasound machine for vascular access.
• Introducer sheath: 6-Fr short sheath.
• Diagnostic catheters: 5-Fr Berenstein catheter.
• Guidewires:
  • 0.035″ hydrophilic Glidewire (180 cm).
  • 0.035″ Bentson wire.
  • 0.018″ V-18 ControlWire (300 cm).
  • 0.014″ Hydro ST (hydrophilic steerable guidewire).
• Catheter: Kumpe catheter.
• Mini access kit (4 Fr, 0.018″ system).
• Syringes and contrast delivery system.
• Saline irrigation.
• Hemostasis and closure supplies, including sutures, skin adhesive, sterile dressings, and compression materials.

Nothing to disclose.

The patient referred to in this video article has given their informed consent to be filmed and is aware that information and images will be published online.