Arteriovenous Fistula Research Articles

Letter to the Editor. Seizure activity may cause early venous drainage in the absence of an arteriovenous fistula or malformation.

Letter to the Editor. Seizure activity may cause early venous drainage in the absence of an arteriovenous fistula or malformation.

Endovascular embolization of a congenital inferior phrenic artery-to-pulmonary arteriovenous malformation: a rare case report

BackgroundPulmonary arteriovenous malformation (PAVM) is abnormal arteriovenous shunts between pulmonary artery (PA) and pulmonary vein, and rarely has congenital direct communications with systemic arteries.Case PresentationA 33-year-old male presented to our hospital with intermittent bloody sputum with no evidence of pulmonary infection, trauma or surgery. Chest computed tomography angiography (CTA) indicated the congenital inferior phrenic artery (IPA)-to-PAVM surrounded by diffuse alveolar hemorrhage located in the lower lobe of right lung. Both the afferent PA and IPA were successfully embolized with coils. Recurrent hemoptysis did not occur during one-year follow up.ConclusionsThe congenital communication between IPA and PAVM is rare, and the abnormal direct shunt would induce hemodynamically unstable condition within PAVM. Endovascular embolization of the afferent PA and IPA is a safe and effective method for this abnormal congenital shunt in lung.

Transcarotid flow reversal for proximal control during cerebral aneurysm clip reconstruction: illustrative case.

Paraclinoid aneurysms can pose an operative challenge during clip reconstruction, given the complex surrounding anatomy and the aneurysmal tendency to maintain turgor despite standard approaches to proximal control. This report demonstrates the use of intraoperative retrograde arteriovenous shunting with the transcarotid artery revascularization (TCAR) system to assist in the safe clip reconstruction of an irregular paraclinoid aneurysm. A 33-year-old woman presented with perimesencephalic subarachnoid hemorrhage and was found to have an incidental 9-mm ophthalmic aneurysm. Coil embolization was not successful. During microsurgical clip reconstruction, the left common carotid artery was exposed to allow for proximal control as well as transcarotid arterial sheath placement. Flow reversal was instituted throughout the aneurysm dissection and clipping, with a visible softening of the aneurysm. Intraoperative angiography confirming successful clip reconstruction was performed utilizing the TCAR sheath. The case was complicated by the development of cerebrospinal fluid rhinorrhea postoperatively, requiring surgical repair. The patient has since made a complete recovery. Transcarotid flow reversal utilizing the TCAR system has potential for use in the surgical treatment of paraclinoid aneurysms, as it may aid in softening the aneurysm for safer dissection and clip reconstruction, protect against aneurysm-associated emboli, and provide an avenue for intraoperative angiography. https://thejns.org/doi/10.3171/CASE24330.

Features associated with arteriovenous fistula patency. A meta-analysis.

It is unclear if cannulation-associated variables such as timing of first cannulation, access creation method, cannulation technique, or needle type are associated with the outcomes of arteriovenous fistulas. We conducted a meta-analysis to investigate such potential associations with 1-year primary patency. Twenty-eight publications with titles that included "arteriovenous fistula," "patency," "cannulation," "metric," "first cannulation," "hemodialysis," "complication," "vascular," "nursing," and "puncture" were retrieved and reviewed. The 1-year primary patency rates ranged from 0.32 to 0.93. Primary patency rates were significantly lower in patients in whom initial cannulation was done less than 1.5 months after fistula creation compared to fistulas first cannulated more than 1.5 months after anastomosis (odds ratio [OR] = 0.41, 95% confidence interval [CI]: 0.32-0.52). The effect of cannulation timing on primary patency rate was attenuated when plastic cannulas were used during the first two to three puncture weeks compared to metal needles (OR = 0.62 vs. 0.34; p = 0.032). Fistulas in the upper arm did not have a higher 1-year primary patency compared to those in the forearm (OR = 1.05, 95% CI: 0.93-1.19). Primary patency of upper arm arteriovenous fistulas was higher in reports from the Americas or Europe compared to reports from Asia. Buttonhole cannulation was not associated with higher patency rates at 1 year compared to rope-ladder cannulation (OR = 1.14, 95% CI: 0.75-1.71). Early cannulation was associated with reduced 1-year arteriovenous fistula patency. This association was reduced when plastic cannulas were used during the initial 2-3 weeks.

Possibilities of endovascular treatment of vascular complications in mine–blast trauma

Objective. To optimize approaches to endovascular treatment of posttraumatic false aneurysms and arteriovenous fistulas in patients with complications of mine–blast trauma. Materials and Methods. The results of examination and treatment of 9 patients with complications of mine–blast trauma were analyzed. False aneurysms of various localizations were detected in 5 (55.6%) patients, and arteriovenous fistulas of the same localization were detected in 4 (44.4%) patients. Results. We performed 5 endoprosthetics with the use of stent grafts to exclude lesions from the circulation, as well as 5 selective embolizations with coils. In 1 patient, embolization with endoprosthetics was performed simultaneously. In all 9 patients, the treatment was technically successful, that is, the technical success of the interventions was 100%. None of the patients had any complications. All patients regressed clinical symptoms after the intervention. Conclusions. Endovascular treatment of post–traumatic false aneurysms and arteriovenous fistulas in patients with mine–blast trauma is highly effective. In all 9 patients with arteriovenous fistulas and false aneurysms, endoprosthetics with stent grafts and selective embolization of lesions with complex anatomy were successfully performed. Further study of the long–term results of treatment of these patients is necessary to increase technical and clinical success.

Nano-based perivascular intervention sustains a nine-month long-term suppression of intimal hyperplasia in vein grafts

Open vascular reconstructions (OVR), including bypass grafts and dialysis access, are standard treatments for cardiovascular and renal diseases. Unfortunately, OVR often fail largely due to intimal hyperplasia (IH), and there are no clinical methods to prevent this complication. Perivascular drug administration during OVR presents a promising strategy for IH suppression. However, durations of drug release from carriers are generally short whereas sustained efficacy is essential for clinical success. This raises a critical question in clinical translation: can IH suppression be realistically maintained long-term (e.g., over 6 months) with short-term perivascular interventions? To address this question, we modified a rat vein-graft model to prolong IH progression. We then applied Pericelle, a nanoparticle/hydrogel hybrid system that we developed for perivascular delivery of rapamycin, an established IH-inhibitory drug. Surprisingly, despite short (∼3-month) drug release, Pericelle demonstrated IH suppression throughout 3, 6, and 9 months with IH reduced from 115.58 ± 27.89 to 40.34 ± 5.18 at 9 months (P < 0.05, n = 6 rats), as indicated by morphometric analysis. Live animal ultrasonography showed the same trend. Consistently, histone-3 lysine-27 trimethylation, an epigenetic mark associated with IH progression, was decreased at 6 months after Pericelle treatment. Moreover, Pericelle exhibited promising efficacy in mitigating IH in a porcine model of arteriovenous fistula that mimics dialysis access. These results suggest that Pericelle-mediated suppression of IH in rat vein-grafts extends much beyond drug release, offering potential solutions to longstanding translational challenges in reducing OVR failure.

Classification, angioarchitecture and treatment outcomes of medullary bridging vein-draining dural arteriovenous fistulas in the foramen magnum region: a multicenter study.

This study aimed to classify medullary bridging vein-draining dural arteriovenous fistulas (MBV-DAVFs) located around the foramen magnum (FM) according to their location and characterize their angioarchitecture and treatment outcomes. Patients with MBV-DAVFs diagnosed between January 2013 and October 2022 were included. MBV-DAVFs were classified into four groups. Jugular vein-bridging vein (JV-BV) DAVF: located in proximity to jugular fossa, Anterior condylar vein (ACV)-BV DAVF: proximity to anterior condylar canal, Marginal sinus (MS)-BV DAVF: lateral surface of FM and Suboccipital cavernous sinus (SCS)-BV DAVF: proximity to dural penetration of vertebral artery. Twenty patients were included, three JV-BV, four ACV-BV, three MS-BV and ten SCS-BV DAVFs, respectively. All groups showed male predominance. There were significant differences in main feeders between JV (jugular branch of ascending pharyngeal artery) and SCS group (C1 dural branch). Pial feeders from anterior spinal artery (ASA) or lateral spinal artery (LSA) were visualized in four SCS and one MS group. Drainage pattern did not differ between groups. Transarterial embolization (TAE) was performed in three, two, one and two cases and complete obliteration was obtained in 100%, 50%, 100% and 0% in JV, ACS, MS and SCS group, respectively. Successful interventions without major complications were finally obtained in 100%, 75%, 100%, and 40% in JV, ACS, MS and SCS group, respectively. JV-BV DAVFs were successfully treated using TAE alone. SCS-BV DAVFs were mainly fed by small C1 dural branches of vertebral artery often with pial feeders from ASA or LSA, and difficultly treated by TAE alone.

Dural arteriovenous fistula may be occluded through recanalization of impaired venous sinuses.

To investigate the effect and safety of recanalization of stenosed or occluded venous sinuses for dural arteriovenous fistulas (DAVFs) and possible mechanism of DAVF formation, patients with DAVF accompanied by venous sinus stenosis or occlusion treated with balloon angioplasty and/or stenting were retrospectively enrolled. The clinical data, treatment outcomes and complications were analyzed. In 7 patients enrolled, the DAVF was Cognard IIa grade in 3 (42.9% or 3/7) and IIa + b in 4 (57.1% or 4/7) patients, including complex DAVFs in 2 (28.6% or 2/7). The angioplasty procedure was successful in all (100%) patients, including complete cure in 3 (42.9% or 3/7) patients with the initial Cognard grade IIa, transformation from Cognard grade IIa + b to I in 2 (28.6% or 2/7) patients, and unchanged Cognard grade IIa + b in 2 (28.6% or 2/7) patients. The symptoms were all improved. At 3-month angiographic follow-up, 5 (71.4% or 5/7) cases were cured, whereas 2 cases still had grade I fistulas but no clinical symptoms. Staged embolization in 2 patients resulted in significant symptom improvement. At the last follow-up of a median 4 years, no clinical symptoms were present in 5 (71.4% or 5/7) patients, intermittent headache in 1 (14.3% or 1/7), and death from trauma in 1 (14.3% or 1/7). In conclusion, endovascular recanalization of occluded or stenosed venous sinuses using balloon angioplasty and stenting is able to induce occlusion of DAVFs and is a safe and efficient treatment approach for DAVFs which are possibly caused by significant pressure increase.

Efficacy of Vascular Access Intervention for Arteriovenous Fistula in the Tobacco Fossa

Efficacy of Vascular Access Intervention for Arteriovenous Fistula in the Tobacco Fossa

Diabetic Charcot neuroarthropathy: A threat to both limb and life.

Diabetic Charcot neuroarthropathy (DCN), first described in 1936, occurs in less than 1% of diabetic patients, but in those diabetic subjects with distal symmetrical polyneuropathy, the overall incidence increases to 30% and the risk is even greater in those with type 1 diabetes. Factors that precipitate DCN are trauma, ischaemia due to arterio-venous shunting, increased osteoclastic activity and inflammation. DCN usually presents with a painless swollen foot and/or ankle which is 'hot to the touch'. These clinical findings are soon followed by characteristic magnetic resonance imaging (MRI) abnormalities and later X-ray changes. The joints that are most typically involved in chronological order are the tarsometatarsals followed by the naviculocuniform, sub-tarsal, talonavicular and metatarsal and tarsophalangeal. The cornerstone of therapy is prolonged (3-12 months) offloading with immobilization. Bisphosphonates may possibly accelerate recovery, whereas other unproven possible therapies include rhPTH, 1-34, calcitonin and methylprednisolone, which are not only ineffective but in some cases may also prolong the time to healing. Denosumab is potentially an efficacious, if unproven, therapy to accelerate healing. The risk of amputation is high and increases in the presence of a foot ulcer. DCN is associated with manifestations of autonomic neuropathy, including cardiac denervation, so that the risks of a cardiac event and heart failure are increased with DCN. Mortality is also increased with DCN, especially in the presence of a foot ulcer. To avoid the recurrence of DCN and especially to lower the risk of the recurrence of a foot ulcer recurrence reconstructive, surgery may be needed.

Comparison of two types of thrombolysis combined with percutaneous transluminal angioplasty for acute thrombosis in arteriovenous fistula and graft

Purpose: To investigate and compare the efficacy of two different types of thrombolysis combined with percutaneous transluminal angioplasty (PTA) for acute thrombosis in arteriovenous fistula (AVF) and graft (AVG). Methods: A total of 128 patients on hemodialysis with acute AVF/AVG occlusion, from May 2021 to May 2023 at Jiangmen Central Hospital, Guangdong, were randomly assigned to study group (catheterdirected thrombolysis) (CDT) comprising of 62 patients and control group (scalp needle thrombolysis) comprising of 66 patients. Patients whose thrombolysis was unsuccessful on the first day, received PTA therapy the next day. Thrombolytic success rates, urokinase dosage, PTA therapy rates, mural thrombus occurrence, and post-thrombolytic complications were evaluated and compared. Result: There was no significant difference in overall thrombolytic success rate, PTA combination rate and incidence of hemorrhage (p &gt; 0.05) between study and control groups. Recanalization rate after urokinase thrombolytic therapy on first day was significantly higher in the study group than in the control group (p &lt; 0.05). Urokinase dosage (first day) of patients whose thrombolytic therapy was successful was significantly lower in the study group than in the control group (p &lt; 0.001). Conclusion: Mechanical fragmentation by angiography catheter combined with urokinase thrombolysis improves efficacy, but shows no advantage when combined with PTA. Additional studies using a larger patient population on anticoagulant therapy and longer investigation time are recommended to enhance the generalizability of this treatment approach.

Recognition of dural to pial supply in high-grade dural arteriovenous fistula: A technical note.

High-grade dural arteriovenous fistulas (DAVFs) are known to demonstrate classical dural supply and can demonstrate pre-existing dural supply and 'pure' arterial supply from pial branches. The latter two are examples of congenital versus acquired pial to dural shunting, respectively. We describe the recognition of dural to pial supply during combined transarterial and transvenous embolization of a high-grade DAVF with holocephalic venous reflux, stressing the importance of careful assessment of this condition with micro catheter injections.

Imaging Evolution of the Development of Dural Arteriovenous Fistula.

Imaging Evolution of the Development of Dural Arteriovenous Fistula.

Microsurgical Treatment of Intracranial Dural Arteriovenous Fistulas: A Collaborative Investigation From the Multicenter Consortium for Dural Arteriovenous Fistula Outcomes Research.

First-line therapy for most intracranial dural arteriovenous fistulas (dAVFs) is endovascular embolization, but some require microsurgical ligation due to limited endovascular accessibility, anticipated lower cure rates, or unacceptable risk profiles. We investigated the most common surgically treated dAVF locations and the approaches and outcomes of each. The Consortium for Dural Arteriovenous Fistula Outcomes Research database was retrospectively reviewed. Patients who underwent dAVF microsurgical ligation were included. Patient demographics, angiographic information, surgical details, and postoperative outcomes were collected. The 5 most common surgically treated dAVF locations were analyzed about used surgical approaches and postoperative outcomes. Univariate analyses were performed with statistical significance set at a threshold of P < .05. In total, 248 patients in the Consortium for Dural Arteriovenous Fistula Outcomes Research database met inclusion criteria. The 5 most common surgically treated dAVF locations were tentorial, anterior cranial fossa (ACF), transverse-sigmoid sinus (TSS), convexity/superior sagittal sinus (SSS), and torcular. Most tentorial dAVFs were approached using a suboccipital, lateral supracerebellar infratentorial approach (39.3%); extended retrosigmoid approach (ERS) (25%); or posterior subtemporal approach (19.6%). All ACF dAVFs used a subfrontal approach; 5.3% also included an anterior interhemispheric approach. Most TSS dAVFs were ligated via ERS (31.3%) or subtemporal (31.3%) approaches. All convexity/SSS dAVFs used an interhemispheric approach. All torcular dAVFs used the suboccipital, lateral supracerebellar infratentorial approach, with 10.5% undergoing simultaneous ERS craniotomy. Angiographic occlusion rates after microsurgery were 85.5%, 100%, 75.8%, 79.2%, and 73.7% for tentorial, ACF, TSS, convexity/SSS, and torcular dAVFs, respectively (P = .02); the permanent neurological complication rates were 1.8%, 2.6%, 9.1%, 0%, and 0% (P = .31). There were no statistically significant differences in development of complications (P = .08) or Modified Rankin Scale at the last follow-up (P = .11) by fistula location. Although endovascular embolization is the first-line treatment for most intracranial dAVFs, surgical ligation is an important alternative. ACF and tentorial fistulas particularly demonstrate high rates of postoperative obliteration.

Percutaneous Deep Venous Arterialization by Balloon Angioplasty without Stent Implantation for Patients with Chronic Limb-Threatening Ischemia Undergoing Hemodialysis: A Retrospective Cohort, Single-Center, Single-Arm Study.

This retrospective, single-center study aimed to determine the efficacy of percutaneous deep venous arterialization in patients on hemodialysis with chronic limb-threatening ischemia. Twenty-one consecutive limbs on hemodialysis with chronic limb-threatening ischemia were treated with percutaneous deep venous arterialization using balloon angioplasty following a failed pedal arterial reconstruction between May 2021 and June 2022. An arteriovenous fistula near the ankle joint was created to ensure sufficient venous flow reversal to the pedal veins. In case of occlusion of the tibial artery, a guidewire was advanced (subintimal) to the ankle joint vicinity was technically important. The primary outcome measures were the 6-month complete wound healing and freedom from major amputation rates; the secondary outcome measure was the 6-month amputation-free survival. Occlusion of all pedal arteries was observed in 17 limbs (81.0%). Arteriovenous fistulas were predominantly created at the distal portions of the posterior tibial artery and vein in 18 limbs (85.7%). No extravasation at the fistulas was observed. Re-intervention was required in 16 limbs (76.2%) due to tibial artery or deep vein occlusion. The 6-month complete wound healing rate was 42.9% (nine limbs), with a median healing time of 85 days (interquartile range: 58-151 days). The 6-month freedom from major amputation and amputation-free survival rates were 90.5% (19 limbs) and 61.9% (13 limbs), respectively. Balloon angioplasty without stent implantation for percutaneous deep venous arterialization is promising for improving the complete wound healing and amputation-free survival rates after pedal artery reconstruction failure. Level 3b, retrospective cohort study.

Bridging the gap between neuroimaging and neurosurgery: a case of epidural arteriovenous fistula with an intradural presentation. Illustrative case.

Epidural arteriovenous fistulas (eAVFs) are rare vascular malformations often mistaken for their intradural counterparts due to similar angiographic features. Differentiation between epidural and intradural vascular lesions is crucial as it impacts surgical planning and prognosis. Despite advancements in diagnostic imaging, these entities can be misinterpreted and challenge management. The authors report the case of a 68-year-old male suspected to have a type I dural arteriovenous fistula based on magnetic resonance angiography and angiographic evaluation. He presented with progressive myelopathy and multiple neurological symptoms exacerbated by recent trauma. A superselective angiogram of the right T10 segmental artery suggested an intradural arteriovenous fistula; however, intraoperatively, the lesion was epidural. The arterialized venous structures were obliterated, and the patient reported significant postoperative symptomatic improvement. This case highlights the critical importance of comprehensive imaging and cautious interpretation in the diagnosis of spinal vascular malformations. It also underscores the need for a multidisciplinary approach to ensure accurate diagnosis and effective treatment. Surgeons must be prepared for intraoperative findings that diverge from preoperative imaging to adapt surgical strategies accordingly. Furthermore, this case contributes to the evolving understanding of eAVFs, suggesting that revised imaging protocols may be required to better distinguish epidural from intradural vascular abnormalities. https://thejns.org/doi/10.3171/CASE24331.

Efficacy of Using a Vessel Dilator during Surgery to Evaluate Vein Diameter and Predict Radiocephalic Arteriovenous Fistula Maturation and Patency

Background: We use vessel dilators to assess the diameter of the target vein during surgery for arteriovenous fistula (AVF) creation in hemodialysis patients. This study investigates the efficacy of using vein diameter as measured using dilators (surgical diameter; SD) versus that as measured by preoperative ultrasonography (ultrasonographic diameter; UD) to predict postoperative complications and patency. Methods: Sixty-three patients who underwent radiocephalic AVF creation and had measurements of UD and SD were retrospectively analyzed. Cutoff values for UD and SD regarding complications were used to dichotomize the patients into high and low groups for comparisons. Results: The 2-year primary and secondary patency rates overall were 66.5% and 88.9%, respectively. The optimal UD and SD cutoff values were 2.4 and 3.5 mm, respectively. The 2-year primary patency rate was higher in the high-SD group than the low-SD group (88.2% vs. 58.6%; p = 0.0426). The 2-year secondary patency rate was significantly higher in the high-UD/high-SD group than the low-UD/low-SD group (91.7% vs. 68.4%; p = 0.0067). Conclusions: Intraoperative measurement of vein diameter using dilators during AVF creation might be a useful method of predicting patency, particularly when SD is used in combination with UD.

Effect of a novel cannulation device for vascular access on AVF maturation in a goat carotid-jugular fistula model.

The Ark is a 3-D printed titanium device designed to be implanted around the draining vein of an arteriovenous fistula (AVF) to facilitate vascular access. The purpose of this study was to assess AVF maturation after Ark implantation in a large animal model. End-to-side AVFs were created between the carotid artery and jugular vein in nine pygmy goats that included three control (AVF only) and six experimental (AVF and Ark device) animals. For experimental animals, an Ark device was implanted approximately 10 cm downstream of the anastomosis at the time of AVF creation. Postoperative ultrasounds and cannulations of the jugular vein fistula were performed over 12 months. At the conclusion of the study, the AVF was ligated and Ark devices along with a segment of the arterialized vein and surrounding tissues were explanted for gross and histological assessment. The control and experimental Ark groups exhibited increased dilation and flow as well as diminished depth underscoring the parallel developments in vascular attributes and AVF maturation between the two groups. Gross pathology, histology, and micro-CT imaging revealed intact endothelium, mature tissue integration throughout the porous Ark device, and no underlying stenosis. No adverse events such as foreign body reaction, skin or vessel erosion were identified. The study showed maturation without stenosis of the fistula in all animals. This study confirmed that the Ark device functions as a scaffold around the access vein, allows fistula maturation, and can be consistently cannulated without infiltrations over a 12-month period in a large animal model.

Correlation between preoperative cephalic vein pathological types and autogenous arteriovenous fistula (AVF) maturation in patients with stage 5 chronic kidney disease.

To explore the correlation between preoperative cephalic vein pathological types and the maturation of autogenous arteriovenous fistula (AVF) in patients with chronic kidney disease (CKD), providing new ideas and methods for clinical prediction of fistula maturation. A retrospective analysis was performed in 80 patients who underwent AVF creation surgery from June 2021 to June 2023 at our hospital. Patients were followed up for 6 months. Patients were classified into the mature group (n = 57) and the power loss group (n = 23) based on the AVF maturation status. Preoperative excised venous tissues were examined using Masson's trichrome staining to compare the intimal area (Ia), medial area (Ma), lumen diameter (Ld), average intimal thickness (Avg It), and average medial thickness (Avg Mt), along with the calculations and comparisons of Ia/Ma, Avg It/Avg Mt ratios. Factors influencing AVF power loss were identified using the multifactorial logistic regression analysis. Ia, Ia/Ma, and Ld were lower in the power loss group compared to the mature group (P < 0.01). No significant difference was found in Avg Mt and Avg It/Avg Mt levels between the two groups (P > 0.05). The level of Avg It was higher in the power loss group (P < 0.05). Avg It was a risk factor (P < 0.001), while Ld was a protective factor for AVF power loss (P < 0.05). The levels of Avg It and Ld in preoperative cephalic vein tissue before AVF formation were correlated with AVF power loss. Early monitoring may improve therapeutic outcomes and prognosis of patients with stage 5 CKD.

Unusual gastrointestinal bleeding - Small intestinal venous ectasias.

A 34-year-old man presented to our emergency department with a 6-day history of bloody stools. He had no complaints of alteration in bowel habits in the stool. He did not consume alcohol and was a non-smoker. The patient had no any previous notable medical history or family history of similar complaints. Physical examination was unremarkable. In the local hospital, laboratory studies showed a hemoglobin level of 6.0g per deciliter (normal range, 11.5 to 15.5). After blood transfusion, an upper gastrointestinal endoscopy and complete colonoscopy did not reveal any bleeding lesion. In our hospital, the patient underwent abdominal contrast-enhanced CT, small intestinal venous ectasias were detected. The selective angiography was performed, but no aneurysm or arteriovenous fistula was found. The gastrointestinal tract bleeding still occurred for an unknown reason. Subsequently, single-balloon enteroscopy was carried out. By oral approach enteroscopy, obvious jejunum venous ectasias were detected.