High-flow Fistula Research Articles

Giant high-flow renal arteriovenous fistula treated by percutaneous embolization

We report the case of a giant renal arteriovenous fistula after renal biopsy in a 30-year-old man with hematuria and hypertension. We performed percutaneous endovascular embolization using macrocoils to exclude the fistula. The patient made an uneventful recovery with no further hematuria and progressive reduction of blood pressure. Follow-up by digital subtraction angiography (DSA) at 6 months showed complete occlusion of the fistula with no evidence of renal parenchymal infarction. Although giant renal arteriovenous fistulas are generally treated by nephrectomy, this case shows that embolization is a reasonable alternative to surgery.

Transcatheter Coil Embolization of a High-Flow Coronary Artery Fistula Using 0.052-Inch Gianturco Coils-A Case Report-

A giant, high-flow coronary fistula is usually difficult to treat by transcatheter coil embolization, but the 0.052-inch Gianturco coil, which is larger and has a stronger shape memory than conventional coils, is now available. Using this device and additional conventional coils, a high-flow coronary artery fistula in a healthy 31-year-old man was successfully embolized. The new Gianturco coil widens the indication for the transcatheter embolization of coronary artery fistulas.

Successful coil embolization of the congenital intrahepatic arteriovenous fistula associated with intrahepatic portal vein aneurysm in an infant

Fistula between the hepatic artery and portal vein, known as hepatoportal arteriovenous fistula, most commonly occur secondary to trauma or malignancy. Congenital hepatoportal arteriovenous fistula is a rare anomaly which causes portal hypertension with the reversal of flow in the portal circulation, leading to hyperaemia and congestion of the bowel, hepatosplenomegaly, causing severe ascites, gastrointestinal bleeding, anaemia and malabsorption. We describe herein a case of a 7-month-old child diagnosed to have congenital high-flow hepatoportal arteriovenous fistula by digital subtraction angiography, who was successfully managed by percutaneous transcatheter embolization of the feeding hepatic artery branches.

Encephalocraniocutaneous Lipomatosis Syndrome in a Child: Association with Multiple High Flow Cerebral Arteriovenous Fistulae

We describe the case of a three-year-old Danish boy born at term by Cesarean due to cardiac insufficiency in the last trimestre of intra-uterine life for which he is being treated with cardiac drugs. At birth, he was noted to have bilateral ocular malformations on the upper eyelids, and diffuse scalp lipoma and alopecia. Due to the retarded growth (score - 3D) he had a MRI and angiography which demonstrated a high flow fistula on the basilar tip artery and another one on the MCA branch treated by endovascluar approach. Intracranial arachnoid cysts, dysplastic cortex, ventricular enlargement and lipoma were noted too, establishing the diagnosis of Encephalocraniocutaneous Lipomatosis Syndrome, a rare disease, especially in bilateral presentation. To our knowledge this is the first observation of ECCL associated with intracranial pial arteriovenous fistulas.

Do AV fistulas contribute to cardiac mortality in hemodialysis patients?

Potential fistula-related problems which may impact on patient survival include high fistula flow with hyperkinetic circulation and cardiac failure, low fistula flow with the risks of underdialysis and fistula thrombosis, vascular access infection with local or systemic manifestations, and possibly induction and maintenance of a microinflammatory state (at least for synthetic grafts). All these complications are much more common with prosthetic grafts than with native arteriovenous (AV) fistulas. Fistula flow should be monitored (e.g., by duplex sonography) to guarantee adequate flow and permit preemptive intervention to avoid fistula thrombosis.

Spontaneous resolution of an idiopathic cervical direct vertebral arteriovenous fistula after partial coil embolization in a patient presenting with myeloradiculopathy

A 53-year old female presented with paresis of the left upper extremity. Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) disclosed a single high-flow vertebral arteriovenous fistula (AVF) with vertebral artery (VA) transection. The AVF was also fed by steal flow from the contralateral VA. The left posterior inferior cerebellar artery (PICA) branched just distal to the fistula. The fistula drained into the neighboring paravertebral veins and refluxed into the intradural venous systems. The dilated drainers compressed the spinal cord. Embolization was attempted at the drainer just behind the fistula orifice using platinum coils. The fistula was still fed slightly by right VA after the embolization, but spontaneous complete obliteration was achieved after one week. The clinical symptoms and signs disappeared. Although, detachable balloon embolization is the quickest and most effective procedure to obliterate a fistula, stepwise embolization using GDC can be considered, and may avoid the normal pressure perfusion break-through phenomenon. Spontaneous obliteration of the fistula after partial embolization in our case may result from intravenous embolization just behind the fistula orifice. It may therefore be a useful approach to the embolization of an AVF to begin the embolization at the venous side of the fistula.

Transvenous Detachable Coil Embolization of Direct & High-Flow Carotid-Cavernous Fistula Alternative of Transarterial Detachable Balloon Embolization

We encountered 8 cases of high-flow and direct carotid cavernous fistula (CCF) since 1994. Four patients were treated with transarterial fistula occlusions using detachable balloons before 1997. Complete obliteration of CCFs with preservation of internal carotid artery (ICA) were achieved in all 4 cases using each one balloon. Three cases were approached to the fistulas via the percutaneous transfemoral approach, but one aged patient needed a direct carotid puncture because of her tortuous vessels. Meanwhile, transvenous embolizations with detachable coils (DCs); Guglielmi detachable coil (GDC), interlocking detachable coil (IDC) and fibered platinum coil were attempted in four cases after 1997; in 2 cases after failure of transarterial approach and in 2 as initial form of treatment. All 4 cases were successfully approached to the cavernous sinuses (CS) through the inferior petorosal sinus (IPS). At first we intended to block dangerous outflow points for the superior ophthalmic vein (SOV), cortical venous reflux (CVR) and contra-lateral CS. And then obliteration of the fistulas were performed with tight packing of GDCs covering the outside of the ICA. At this time, the arteriovenous shunts were disappeared abruptly, so we finished all procedure without occlusion of IPS.We compared the two methods and concluded that the transvenous embolizaton with DCs is an useful alternative of transarterial detachable balloon therapy of high flow CCF, especially when transarterial approach is difficult or proper balloons are not available.

Diagnosis and endovascular treatment of vertebral arteriovenous fistulas in neurofibromatosis type 1.

We present diagnostic problems, strategies, techniques and material selection for endovascular treatment of high flow arteriovenous fistula (AVF) of tortuous and fragile vertebral artery (VA) with neurofibromatosis type 1 (NF1). Diagnosis of NF1 was easy in four of our cases because of neurofibromatosis, skin pigmentation and various skeletal abnormalities. These stigmas of NF1 were lacking in one case, and the only clue to the diagnosis was ovoid bone defects of the skull vault. Diagnosis was made by performing biopsy of scalp neurofibromas incidentally found on CT. In two initial cases, venous varix were packed with coils by transvenous approach after the transarterial embolisation failed to completely cure the fistula. In three recent cases, blood flow through the fistula was markedly reduced as an initial step by placing detachable coils into the distal and proximal stumps of the afferent VA. Then a liquid adhesive was injected under systemic hypotension to completely occlude the fistula. Control angiography revealed that the AVFs were completely occluded in all cases. Longterm angiographical and clinical status have been stable in all cases. Trying to attain complete occlusion of fistulas using detachable balloons is not an appropriate treatment option for high flow fistulas situated on markedly dilated, tortuous and fragile VAs of patients with NF1. Also, trapping of fistulas is not justified because of the numerous potential feeding pedicles, and makes the following procedure difficult.

Complex Vertebral Arteriovenous Fistula and Ruptured Aneurysm in Neurofibromatosis:A Therapeutically Challenging Case

The objective and importance of this study was to describe the challenges encountered with treating a high-flow vertebral arteriovenous fistula (AVF) and ruptured aneurysm in a patient with life-threatening hemorrhage. A 36-year-old female with Neurofibromatosis type 1 (NF1) presented 2 weeks after uneventful cesarean section with a rapidly expanding pulsatile neck mass. Angiography demonstrated a complex left vertebral AVF and multiple associated vertebral artery aneurysms. Emergent endovascular coil embolization was performed using a retrograde and antegrade approach to occlude the fistulas and trap the ruptured aneurysm, successfully treating the acute hemorrhage. Subsequent definitive therapy was accomplished utilizing a combined neurointerventional and neurosurgical strategy of direct-puncture acrylic embolization and ligation of the vertebral artery. Recent advances in neurointerventional technology allow novel approaches in the primary and/or preoperative treatment of complex vascular lesions such as those seen in NF1.

Endovascular therapy of arteriovenous fistulae with electrolytically detachable coils.

We report our experience in using Guglielmi electrolytically detachable coils (GDC) alone or in combination with other materials in the treatment of intracranial or cervical high-flow fistulae. We treated 14 patients with arteriovenous fistulae on brain-supplying vessels--three involving the external carotid or the vertebral artery, five the cavernous sinus and six the dural sinuses--by endovascular occlusion using electrolytically detachable platinum coils. The fistula was caused by trauma in six cases. In one case Ehlers-Danlos syndrome was the underlying disease, and in the remaining seven cases no aetiology could be found. Fistulae of the external carotid and vertebral arteries and caroticocavernous fistulae were reached via the transarterial route, while in all dural fistulae a combined transarterial-transvenous approach was chosen. All fistulae were treated using electrolytically detachable coils. While small fistulae could be occluded with electrolytically detachable coils alone, large fistulae were treated by using coils to build a stable basket for other types of coil or balloons. In 11 of the 14 patients, endovascular treatment resulted in complete occlusion of the fistula; in the remaining three occlusion was subtotal. Symptoms and signs were completely abolished by this treatment in 12 patients and reduced in 2. On clinical and neuroradiological follow-up (mean 16 months) no reappearance of symptoms was recorded.

Covered Stent Placement for Neurovascular Disease

We describe an endovascular technique in which covered stents were used to occlude a parent vessel. In one patient, with a giant paraclinoid aneurysm, a Gortex-covered Palmaz stent was used to occlude the cervical internal carotid artery and to create thrombosis in the aneurysm. In the second patient, with a high-flow vertebrojugular fistula, a hooded stent provided definitive treatment after an attempt to close the fistula by detachable balloon therapy failed. Follow-up of these patients revealed stable stent position and no untoward effects of permanent vessel occlusion.

Paediatric Spinal Arteriovenous Malformations: Angioarchitecture and Endovascular Treatment

This is a retrospective review of the clinical records and imaging of 14 children with spinal arteriovenous malformations referred to the neurointerventional service at our institution. The lesions are categorized by anatomic location into subpial (5 cases), epidural (3 cases), and paraspinal (6 cases). There were no dural arteriovenous fistulas in this group. The subpial lesions include both the intramedullary arteriovenous malformations (2 cases) and the perimedullary arteriovenous fistulas (3 cases). Two of the patients with perimedullary fistulas were first cousins and both had Rendu-Osler-Weber syndrome. The six paraspinallesions were vertebral-vertebral fistulas with five of these located at the first cervical metamere. Eleven cases (79%) were arteriovenous fistulas and three cases (21 %) were arteriovenous malformations with a nidus. There were nine (82%) high flow arteriovenous fistulae and two (18%) low flow arteriovenous fistulae. The ages range from seven months to 15 years, with a mean age of seven years. There were nine males and five females. Clinical presentations included: bruit alone (6 patients), progressive scoliosis (1 patient), pain (2 patients), neurologic deficit (4 patients) and one case of Cobb's syndrome. Management included: no treatment (1 patient), endovascular embolisation (10 patients) and surgery (3 patients). Of the patients who underwent endovascular treatment all were treated from the arterial side. Two patients were treated by N-butyl cyanoacrylate (NBCA) alone, two with NBCA and coils, one with balloons alone, three with balloons and coils and two with coils alone. In the endovascular treatment group, nine fistulae were completely obliterated (all high flow fistulae) and one patient had partial treatment (a spinal cord arteriovenous malformation). There were no complications from endovascular treatment.

MR cisternography: a new method for the diagnosis of CSF fistulae.

The aim of this study was to compare a new MRI method for detecting the existence of cerebrospinal fluid (CSF) fistulae, i. e. MR cisternography, with CT cisternography. In a prospective study, 30 patients with post-traumatic CSF fistulae were examined. The MR examinations were performed with a 1.0-T whole-body MR system, using two T2(*)-weighted sequences, a 3D PSIF (time-inversed fast imaging with steady-state precession, FISP) and a 3D constructive interference steady-state (CISS) sequence. The results of MRI and CT cisternography were compared with the surgical findings. The sensitivity in detecting CSF fistulae with MR cisternography (PSIF: 89.9 %; CISS: 93.6 %) was higher than with CT cisternography (72.3 %). The sensitivity of CT cisternography at detecting CSF fistulae in patients with a size of dural lesion less than 2 mm or in patients with multiple dural lesions is significantly lower compared with the MR method. Although the localization of CSF fistulae always proved possible with MR cisternography, this could only be accomplished wih CT in 70 % of cases. The MR cisternography technique is a new examination method with a higher sensitivity for the detection of CSF fistulae than CT cisternography. The CISS technique is superior compared with PSIF and should be used in patients with high-flow CSF fistulas.

Experimental repair of venous valvular insufficiency using a cryopreserved venous valve allograft aided by a distal arteriovenous fistula

Purpose: To evaluate the patency and hemodynamic impact of a cryopreserved allograft venous valve transplanted to the superficial femoral vein (SFV) of a canine insufficiency model aided by a distal arteriovenous fistula (dAVF). Methods: Eight greyhounds had intravenous hemodynamic parameters measured (venous filling time [VFT], 90% of venous refilling time [VRT 90], and simulated ambulatory venous pressure [AVP]) before (T 0) and after complete hindlimb venous valvulotomy (T 1) to produce venous insufficiency. Simultaneously, a valve-containing vein segment was harvested from the opposite SFV or external jugular vein (n = 1) and cryopreserved. Three weeks later a blood type–matched cryopreserved valve was transplanted to the insufficient SFV aided by a low-flow (n = 4) or high-flow (n = 4) dAVF. The fistula was ligated in 3 to 6 weeks, and venous indexes (T 2) were obtained 3 weeks later. Analysis of variances compared the venous indexes at T 0, T 1, and T 2 for statistical significance. Gross and histologic inspection assessed valve integrity. Results: Two valves aided by a low-flow dAVF exhibited thrombosis and scarring. The hemodynamics of the six remaining valves demonstrated normalization of the VRT 90, an AVP consistent with insufficiency, and a VFT between normal and total venous insufficiency. The patent valves were normal on gross examination and by histologic examination with signs of normal external healing. Conclusions: A cryopreserved venous valve allograft transplanted to the SFV of an incompetent hindlimb partially corrects venous hemodynamics. A high-flow arteriovenous fistula most consistently preserves transplant patency. (J Vasc Surg 1997;26:817-22.)

Vein of Galen vascular malformations in infants: clinical, radiological and therapeutic aspect.

A series of 14 vein of Galen vascular malformations diagnosed in the pediatric populations and treated at the Hospital for Sick Children-Necker, Paris, between 1988 and 1994 is presented. Five of the patients were diagnosed in the neonatal period, of whom 4 presented with life-threatening, intractable cardiac decompensation and high-flow arteriovenous fistulae. Embolization was performed on vital indications in 4 patients during the first week after birth. One embolization failed with fatal outcome. Of the 3 who were embolized, 2 succumbed within 1 week and 1 survived with marked improvement of cardiac symptoms. The older children presented with hydrocephalus and neurologic symptoms. The 10 patients older than 1 year were embolized. These procedures were successful in 90 %, with hemodynamic stabilization and improvement of clinical symptoms. In this group the mortality rate was 10 %. The total mortality rate was 29 %. Hydrocephalus was secondary to a compression of the Sylvian aqueduct in 44 % of cases. Five patients had ventricular drainage before embolization followed by a staged elective embolization. Transarterial embolizations were performed in 11 patients, whereas 2 patients were embolized via the transvenous route.

Quantified Partial Embolisation in a Vein of Galen Malformation with Congestive Cardiac Failure

The aim of the study was to quantify embolisation in a vein of Galen malformation by intraluminal measurements of flow velocities in the feeding vessels and to test a new O.014-inch Doppler guide wire in the paediatric population. The examination was performed in a seven month old boy who presented with a vein of Galen malformation combined with congestive cardiac failure from birth. The measurements showed a decrease of the systolic and diastolic velocities and an increase in the effective downstream vascular resistance after closure of the high flow fistula. The decrease of the diastolic velocities after embolisation was more prominent because of the reduction of the sump effect responsible for the high diastolic velocity before embolisation. The reduction of about 40% of the vein of Galen malformation estimated with morphological criteria was associated with a decrease of the diastolic velocity in the basilar artery of about 50%. The clinical improvement led to the discontinuance of most of the cardiac treatment over a few days. These measurements seem to offer the possibility to assess the necessary reduction of the shunt to relieve CCF in a vein of Galen malformation.

Pediatric Thoraco-lumbar Paraspinal Arteriovenous Fistulas along the Segmental Nerve

To characterize the clinical presentation, imaging features and endovascular treatment of paraspinal non-vertebral arteriovenous fistulas along the segmental nerve. Retrospective review was performed on the five patients identified in our database covering 1985 to 2003. All patients presented with an incidentally found continuous murmur over the upper paraspinal or parasternal regions before three years old. In four patients, the AV fistula was in the mid-thoracic level and at L3 in one. All AV fistulas were a high-flow single-hole fistula at the neural foramen with venous drainage into paraspinal and epidural veins without intradural reflux. All fistulas were endovascularly occluded in the same session as the diagnostic angiography. The fistula was occluded with detachable coils in one case and with N-butylcyanoacrylate (NBCA) with flow control in four cases. Complete occlusion of the fistula was obtained in all cases and all patients remained neurologically intact at the last follow up (average six years). Non-vertebral paraspinal arteriovenous fistula along the segmental nerve is a specific disease entity seen in children. Embolization is the first choice of treatment for this disease.

Changes of the Renal Arteries Accordding to Various Embolic Materials

The transarterial embolization has been widely used to control bleeding. It has a variety of clinical utility; to reduce bleeding on the surgical field, to reduce the size of malignant tumor as a preopearative treatment, to treat arteriovenous malformation or arterial aneurysm as a curative method and to promote life quality of patient with diffuse or multiple hepatocellular carcinoma as a palliative treatment, etc. With the advance of modem technology, various embolic materials have been also developed. However, it has not been fully investigated of histopathologic changes of the embolized organs according to the embolic materials used. This study was undertaken to investigate the histopathologic changes of embolized renal artery in rabbit by various embolic materials, according to each embolic material and to time passed by after embolization. Of the 5 arteries embolized by ethylene vinyl alcohol copolymer(EVAL), one showed abscess formation in embolized kidney. The other 4 allowed to perform further pathologic study: within a week after embolization there was no any specific change in vessels, however, minimal endothelial hypertrophy was observed following 2 weeks of embolization. Of the 8 renal arteries embolized by N-buthyl-2-cyanoacrylate(Histoacryl), 4 showed total occlusion of the main renal arteries as well as renal infarction, which reflects the strong adhesiveness of Histoacryl to vascular wall. The other 4 showed fibrinoid degeneration in vascular wall within a week. However, further change was not observed thereafter. In all the 5 renal arteries embolized by polyvinyl alcohol(Ivalon), there were infiltration of inflammatory cells along the vessel walls, within one week, which represents vasculitis. They showed some fibrosis with appearance of giant cells in the vessel wall two weeks after embolization and also showed marked fibrosis of connective tissues surrounding vessels two months after embolization, respectively. The results suggest that EVAL is useful for the embolization of hypervascular lesion with limited arteriovenous fistula, Histoacryl for the curative treatment of the lesion with high blood flow or severe arteriovenous fistula, and Ivalan for palliative treatment of malignant tumor or arteriovenous malformation, respectively.

Transesophageal Echocardiographic Diagnosis of a Congenital Circumflex Coronary Artery to Coronary Sinus Fistula in an Adult

We report a congenital circumflex coronary artery to coronary sinus arteriovenous fistula diagnosed by transesophageal echocardiography in a 38‐year‐old asymptomatic male. The coronary arteriovenous fistula was suggested by two‐dimensional transthoracic color Doppler. A first nondiagnostic angiography was performed, and it was during the second one, that the fistula could finally be visualized after a special dye technique was used. The high fistula flow rate prevented us from seeing it with regular dye concentration. Transesophageal echocardiography was precise in the anatomical and hemodynamic evaluation and it was essential in guiding the angiographic examination and surgical repair.

Radiosurgery of carotid-cavernous fistulae.

25 cases of carotid-cavernous fistulae (CCF) who underwent radiosurgery with a conventional gamma source from 1977 to 1992 are reported. 22 were low-flow, spontaneous CCFs and 3 were high flow fistulae which had undergone a previous trapping. The total dose delivered was 30 to 40 Gy. 91% to patients with low-flow CCF cured after radiosurgery in a mean time of 7.5 months, presenting improvement in a mean time of 2.3 months. Only one of the high-flow fistulae was cured. Follow-up period ranged between 14 years and 15 months (mean: 50 months). No recurrence was recorded in any case. While intravascular embolotherapy is the treatment of choice for high-flow fistulae, stereotactic radiosurgery may be the elective treatment for low-flow CCF.