Treatment of hemodialysis graft pseudoaneurysms with stent grafts: institutional experience and review of the literature

The usefulness and feasibility of placing a clinch knot with a guidewire to achieve temporary hemostasis in arteriovenous dialysis access interventions

PURPOSE

To evaluate the usefulness and feasibility of using a reversible clinch knot with a guidewire in place rather than eliminating the access route during an arteriovenous hemodialysis access (AV access) intervention using the facing sheath technique.

MATERIAL AND METHODS

From July 2016 to June 2019, we retrospectively studied 78 sessions performed as interventional treatment for arteriovenous (AV) hemodialysis (HD) access using the "facing-sheath technique." In all sessions, all antegrade sheaths were removed while a 0.035-inch guidewire remained in place with purse-string suture and the clinch knot. Seventy-two sessions were performed in patients with thrombosed AV accesses (69 arteriovenous grafts [AVGs] and three arteriovenous fistulas [AVFs]), and six sessions were carried out to treat non-thrombosed AV accesses (four AVGs and two AVFs). We evaluated whether proper hemostasis and successful reinsertion of the sheath over the wire into the clinch knot was achieved. Clinical success was defined as achieving prompt restoration of blood flow for AV access, and the postintervention primary and secondary patency were also evaluated.

RESULT

In all 87 clinch knots created in 78 total sessions, proper hemostasis was achieved. All clinch knots that required reversal for additional procedures were successfully reopened (55 clinch knots in 50 sessions). The postintervention primary patency rates at 1, 3, and 6 months, and at 1 year were 77.8%, 68.9%, 55.6%, and 33.3%, respectively. The postintervention secondary patency rates at 1, 3, and 6 months, and also at 1 year were 93.3%, 91.1%, 86.7%, and 86.7%, respectively.

CONCLUSION

Our AV access intervention which used a clinch knot with purse-string suture while the guidewire remained in place was both useful and feasible for maintaining temporary hemostasis.

Spanish Clinical Guidelines on Vascular Access for Haemodialysis

Vascular access for haemodialysis is key in renal patients both due to its associated morbidity and mortality and due to its impact on quality of life. The process, from the creation and maintenance of vascular access to the treatment of its complications, represents a challenge when it comes to decision-making, due to the complexity of the existing disease and the diversity of the specialities involved. With a view to finding a common approach, the Spanish Multidisciplinary Group on Vascular Access (GEMAV), which includes experts from the five scientific societies involved (nephrology [S.E.N.], vascular surgery [SEACV], vascular and interventional radiology [SERAM-SERVEI], infectious diseases [SEIMC] and nephrology nursing [SEDEN]), along with the methodological support of the Cochrane Center, has updated the Guidelines on Vascular Access for Haemodialysis, published in 2005. These guidelines maintain a similar structure, in that they review the evidence without compromising the educational aspects. However, on one hand, they provide an update to methodology development following the guidelines of the GRADE system in order to translate this systematic review of evidence into recommendations that facilitate decision-making in routine clinical practice, and, on the other hand, the guidelines establish quality indicators which make it possible to monitor the quality of healthcare.

Utilization of stent grafts in the management of arteriovenous access pseudoaneurysms

Objective Endovascular stent graft repair for exclusion of pseudoaneurysm is currently being explored to replace open surgical repair as current management. The objective of the study was to evaluate the clinical safety and efficacy of endovascular stent graft intervention in pseudoaneurysms complicating arteriovenous reconstructions in patients on chronic hemodialysis. Methods A retrospective analysis of all pseudoaneurysms treated with stent grafts at our institution over a period of five years was performed. The indications for endovascular intervention included bleeding from the pseudoaneurysm, infection, and significant skin compromise overlying the pseudoaneurysm or combination of the above. The rates of technical success, complication, and primary patency were measured at one-week, one-month, and six-month follow-up. Results A total of 33 endovascular stent graft interventions in 29 patients were performed for the treatment of pseudoaneurysms. The average age of patients was 68 years (range 31-90 years), with 13 female. Diabetes and hypertension were present in 15 and 22 patients, respectively. In eight patients, there was evidence of active infection at the fistula site. The choice of stent grafts include Viabahn ( n = 31), Wallgraft ( n = 1), and i-Cast ( n = 1). The initial technical success rate was 94%. The two failed interventions included occlusion of inflow artery with immediate conversion to open procedure ( n = 1) and incomplete pseudoaneurysm exclusion ( n = 1). Primary patency at one month and six months was 83 and 60%, respectively. An additional balloon angioplasty of outflow tract or central stenosis was performed in 18 cases (54%). The explanation of stent grafts due to persistent or recurrent bacteremia/site infection was required in four out of eight patients. The average time to explanation was 93 days (range 6-204 days). Conclusion The stent graft implantation is a safe, minimally invasive and efficient way to control and manage arteriovenous accesses with pseudoaneurysms. In the presence of infection, this approach may be less durable.

Aneurysms in Vascular Access: State of the Art and Future Developments

A master class was held at the Vascular Access at Charing Cross (VA@CX2017) conference in April 2017 with invited experts and active audience participation to discuss arteriovenous (AV) vascular access aneurysms, a serious and common complication of vascular access (VA). The natural history of aneurysms in VA is poorly defined, and although classifications exist they are not uniformly applied in studies or clinical practice. True and pseudo aneurysms of AV access occur. Whilst an AV fistula by definition is an abnormal dilatation of a blood vessel, an agreed definition of 18 mm, or 3 times accepted maturation diameter, is proposed. The mechanism of aneurysmal dilatation is unknown but appears to be a combination of excessive external remodeling, wall changes due to injury, and obstruction of outflow. Diagnosis of AV aneurysms is based on physical examination and ultrasound. Venography and cross-sectional imaging may assist and be required for the investigation of outflow stenosis. Treatment of pseudo aneurysms and true aneurysms of VA (AVA) is not evidence-based, but relies on clinical experience and available facilities. In many AVA, a conservative approach with surveillance is suitable, although intervals and modalities are unclear. Avoidance of rupture is imperative and preemptive treatment should aim for access preservation, ideally with avoidance of prosthetic materials. Different techniques of aneurysmorrhaphy are described with good results in published series. Although endovascular approaches and stenting are described with good short-term results, issues with cannulation of stented areas occur and, while possible, this is not recommended, and long-term access revision is recommended.

Endovascular Stent Graft Repair is an Effective and Safe Alternative Therapy for Arteriovenous Graft Pseudoaneurysms

OBJECTIVE/BACKGROUND

Pseudoaneurysm formation occurs in 2-10% of hemodialysis arteriovenous grafts (AVGs). Surgical repair often requires pseudoaneurysm resection, interposition graft placement, and insertion of a catheter as a bridge. Endovascular stent graft repair is a controversial alternative therapy. This study was performed to examine the effectiveness and mid-term outcomes of stent graft repair for AVG pseudoaneurysms.

METHODS

All patients who had undergone stent graft repair for AVG pseudoaneurysms between December 2012 and July 2015 were identified from hospital medical records for retrospective analysis. Outcome measures were technical success, early and late complications, and primary and secondary patency rates.

RESULTS

A total of 37 stent graft repairs of AVG pseudoaneurysms were performed in 35 patients (42.9% men; mean age 66.9 years). The mean time from AVG creation to pseudoaneurysm repair was 69 months. The indications of treatment (as per the institutional policy) were large pseudoaneurysm (56.7%), impending rupture (27.1%), and bleeding (16.2%). Mean pseudoaneurysm diameter was 23.0 mm. The most common diameter and length of stent graft used were 7 mm (67.6%) and 50 mm (48.6%), respectively. Technical success was 100%. Only one early complication occurred after stent graft repair, which was due to recurrence of the pseudoaneurysm as a result of a short landing zone. Late complications included infection (17.1%) and thrombosis (37.1%). The 1, 6, and 12 month primary patency rates were 89.2%, 55.5%, and 22.0%, respectively. The 1, 6, and 12 month secondary patency rates were 100%, 88.6%, and 78.6%, respectively. The median follow up was 12.3 months.

CONCLUSIONS

The study demonstrates that endovascular stent graft repair is an effective and safe alternative therapy for AVG pseudoaneurysms. However, the rate of thrombosis and infection was high and needs to be balanced against open surgery in future studies.

Approach to the Swollen Arm With Chronic Dialysis Access: It's Not Just Deep Vein Thrombosis

The purposes of this pictorial essay are as follows: (1) Review a systematic approach to using sonography in the initial evaluation of patients with acute arm swelling and permanent dialysis access. (2) Identify normal grayscale and Doppler findings in arteriovenous fistulas and grafts. (3) Discuss a spectrum of vascular differential diagnoses for arm swelling in this setting, including stenosis of the access, draining vein complications, thrombosis, steal syndrome, and aneurysms, as well as several nonvascular causes. (4) Recognize findings that warrant further imaging evaluation or intervention.

True aneurysm in autologous hemodialysis fistulae: definitions, classification and indications for treatment

Introduction

Definition, etiology, classification and indication for treatment of the arteriovenous access (AVA) aneurysm are poorly described in medical literature. The objectives of the paper are to complete this information gap according to the extensive review of the literature.

Methods

A literature search was performed of the articles published between April 1, 1967, and March 1, 2014. The databases searched included Medline and the Cochrane Database of Systematic Reviews. The eligibility criteria in this review studies the need to assess the association of aneurysms and pseudoaneurysms with autologous AVA. Aneurysms and pseudoaneurysms involving prosthetic AVA were not included in this literature review. From a total of 327 papers, 54 non-English papers, 40 case reports and 167 papers which did not meet the eligibility criteria were removed. The remaining 66 papers were reviewed.

Results

Based on the literature the indication for the treatment of an AVA aneurysm is its clinical presentation related to the patient's discomfort, bleeding prevention and inadequate access flow. A new classification system of AVA aneurysm, which divides it into the four types, was also suggested.

Conclusions

AVA aneurysm is characterized by an enlargement of all three vessel layers with a diameter of more than 18 mm and can be presented in four types according to the presence of stenosis and/or thrombosis. The management of an AVA aneurysm depends on several factors including skin condition, clinical symptoms, ease of cannulation and access flow. The diameter of the AVA aneurysm as a solo parameter is not an indication for the treatment.

Aneurysm Formation and Infection in AV Prosthesis

In contrast to autogenous arteriovenous (AV) fistulae where true aneurysms are the most frequent type, aneurysms in prosthetic AV grafts are mostly false aneurysms and less frequently anastomotic ones. Indications for repair comprise false aneurysms exceeding twofold the graft diameter, those with rapid enlargement or with skin thinning or erosion, the ruptured, those causing pain or severely limiting the cannulable area and the infected ones. They can be managed either with conventional surgery or with endovascular techniques; However, conventional surgery represents the current standard treatment consisting of either aneurysm resection and interposition graft in situ or resection/exclusion and bypass via a new route to avoid a potentially contaminated area.

How I do it: endovascular treatment of arteriovenous graft pseudoaneurysms-watch out for the mouth

We present a case of arteriovenous graft pseudoaneurysms treated endovascularly with stent grafts and make suggestions regarding the technique of evaluating the pseudoaneurysms and choosing the proper location to deploy the stent grafts to maximize the outcomes and minimize the length of the graft covered by the stent. We also comment on the selection of lesions that are suitable to be treated with this technique.

Endovascular Repair of Symptomatic Hemodialysis Access Graft Pseudoaneurysms

Aim

Repeated needle punctures of arteriovenous hemodialysis grafts can lead to the development of pseudoaneurysms. As they enlarge, graft pseudoaneurysms are associated with significant morbidity and require treatment. We present our single-center experience using stent grafts in selected patients to exclude symptomatic hemodialysis graft pseudoaneurysms.

Materials and Methods

Between March 2007 and December 2010, 11 consecutive patients (7 men and 4 women, mean age 57 years) underwent percutaneous endovascular repair of symptomatic hemodialysis access graft pseudoaneurysms. Indications for treatment were rapidly enlarging pseudoaneurysm in 5 patients, high venous pressures, limb edema and pseudoaneurysm in 3, skin breakdown over the pseudoaneurysm site in 2 and acute rupture and bleeding in 1 patient. No patient was lost to follow-up.

Results

Technical success across the 11 patients was 90.9%. The patient who presented with rupture required ligation of the access due to continuous bleeding after stent graft insertion. Balloon angioplasty of a separate hemodynamically significant stenosis at the time of stent graft insertion was performed in 7 of 11 (63.6%) patients. The primary access patency rates were 72.7% (95% CI of 0.390-0.939) at 3 months and 36.4% (95% CI 0.109-0.692) at 6 months. Secondary access patency rates were 72.7% at 6 months (95% CI 0.233-0.832). There were no procedure-related complications. Mean follow-up was 9 months (range 2-29 months).

Conclusions

Endovascular treatment of symptomatic hemodialysis graft pseudoaneurysms is safe and effective with similar patency rates to surgical approaches. Importantly, this approach allows aggressive management of associated access circuit stenoses at the same time and avoids interval tunneled dialysis line insertion.

Endograft salvage of hemodialysis accesses threatened by pseudoaneurysms

OBJECTIVE

Currently, no formal practice guidelines exist regarding the use of endografts to exclude hemodialysis access pseudoaneurysms and prolong access lifespan in dialysis patients. We evaluated the efficacy of percutaneous endograft placement for exclusion of hemodialysis access pseudoaneurysms.

METHODS

Between July 2005 and October 2009, 32 patients were prospectively evaluated. Twenty-four patients were actively enrolled in the study based upon clinical and ultrasonographic evaluation of their hemodialysis accesses. Self-expanding covered endografts were placed percutaneously to exclude access pseudoaneurysms. Patients were evaluated at 2 and 6 months to assess for graft patency, access or outflow stenosis, endoleak, or stent graft migration.

RESULTS

No procedural complications resulted from these interventions. An average of 1.8 endografts was placed per patient, with patients requiring between 1 and 3 endografts to exclude pseudoaneurysms. Primary-assisted patency was 83% at completed 2-month follow-up and 54% at 6-month follow-up. At 12 months, primary-assisted patency was 50%. Eleven patients left the study before 6-month follow-up: five (21%) required explantation secondary to infection between 1 and 4 months; three (13%) were lost to follow-up; two (8%) died of unrelated causes; and 1 requested explantation citing pain from the "stent poking the vein." Mean time to explantation secondary to infection was 2.4 months. Mean duration of patency was 17.6 months with a range from 0 to 76 months. Mean duration of patency for patients who completed 6-month follow-up was 28.7 months. The longest duration of patency is 6 years 4 months, after stent fracture and subsequent placement of a new stent at 6 years 2 months. One other incident of stent fracture occurred at 36 months. Dialysis patterns were not interrupted in either patient.

CONCLUSIONS

The long-term results demonstrate that endograft salvage of failing hemodialysis accesses is a viable and safe alternative to open surgical revision that excludes pseudoaneurysms while maintaining uninterrupted access patency. A larger sample size and longer follow-up are needed to support the study data.

Role of stent grafts for the treatment of failing hemodialysis accesses

Covered stents or stent grafts are exciting new products with multiple applications for patients with vascular disease, including hemodialysis access-related complications. Although most of the current uses of stent grafts in these settings are "off-label" (ie, not approved by the US Food and Drug Administration) several studies are currently underway to provide the necessary data to support their application. It is clear that stent grafts provide a rapid, effective means for endovascular repair of ruptured access vessels. The commercially available devices and their current applications for treating access-related complications, including aneurysms/pseudoaneurysms, venous outflow stenoses, cephalic arch lesions, ruptures, and diffuse access stenoses, will be reviewed in this article. Available data are reported along with our current clinical practice and algorithms.

Stent graft treatment for hemodialysis access aneurysms

BACKGROUND

Aneurysms that develop in arteriovenous accesses as a result of repeated punctures are sometimes complicated by infection or ischemia causing sloughing of the overlying skin, which may endanger the access and risk major bleeding and other complications. Surgical revision may necessitate the temporary use of a central venous catheter until dialysis can be resumed via the access. We used stent grafts in selected patients for the exclusion of access aneurysms.

METHODS

Twenty of 63 patients requiring access revision for complication of an aneurysm from February 2005 to December 2009 underwent ambulatory endovascular stent graft deployment. Indications included signs of impending rupture, questionable viability of overlying skin, pain, infection, and limitation of cannulation sites by the size or number of the aneurysms. Endovascular treatment always included angioplasty of associated outflow or central vein stenoses at the same ambulatory session.

RESULTS

Twenty patients with complicated access aneurysms were treated by endovascular stent graft exclusion at an average of 4.8 ± 4.3 years (range, 0.2 to 16.1 years) after access construction: nine graft pseudoaneurysms, nine native vein aneurysms, and two acute iatrogenic pseudoaneurysms. Six patients had skin erosion over the aneurysm, and 12 had painful aneurysms and clinical signs of compromised blood supply to the skin. Another two patients with an acute giant false aneurysm occurring during endovascular procedures were treated in the same interventional session by the stenting technique to control bleeding. All the aneurysms underwent endovascular exclusion without complications. Only one infected puncture site failed to heal within 2 months of stenting and was closed surgically 10 months later due to persistent localized graft infection, but with no further bleeding episodes. Only one aneurysm did not reabsorb within 3 months. Patients with painful skin ischemia had immediate pain relief. All patients also had stenosis in the draining veins necessitating additional percutaneous transluminal angioplasty. Only one patient required hospitalization (for intravenous antibiotic treatment of staphylococcal sepsis). No patients required a central catheter for hemodialysis. One access occluded due to cephalic arch stenosis in a noncompliant patient. Functional patency was 87% at 12 months, with a median follow-up of 15 months (range, 6.3 to 55.5 months).

CONCLUSION

Endovascular treatment with stent grafts in complicated access aneurysms is a simple, safe and rapid ambulatory procedure that enables treatment of both the aneurysm and its accompanying draining vein stenosis. It enables continued cannulation of the existing access and avoids the use of central catheters.