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Arteriovenous Fistula

AV-Fistula

Arteriovenous fistula, abbreviated as AVF, constitutes a pathological or surgical connection between an artery and vein. It can be present in any region of the body.


Presentation

Arteriovenous fistulas (AVFs) are pathological or surgical vascular connections between arteries and veins. They can be congenital or acquired defects, for example after a penetrating trauma or an aneurysmal rupture. The symptomatology depends on the location and regional anatomy of AVF. Surgical AVF is used for long-term vascular access in hemodialysis.

Usually, acquired AVFs lead to a mass that can be palpated, transmits pulses, and a bruit can be heard during auscultation. These masses are commonly observed in an extremity previously affected by a significant traumatization. Symptoms of high-output congestive heart failure may also be reported, most frequently if the flow via the AVF is greater than 1/5 of the cardiac output, and include peripheral edema, cough, fatigue, shortness of breath, and ascites [1].

AVFs may lead to serious complications such as hemorrhage and neurological impairment [2].

With regard to congenital AVFs, the region where they are formed dictates the symptomatology. More specifically:

  • AVFs in extremities

Symptoms may fail to arise for years after the patient is born. Similarly to acquired AVFs, congenital AVFs located on the extremities induce peripheral edema and hypertrophy of the extremity in young patients. This manifestation is aggravated when the AVF is found in the lower part of the extremity [3]. The clinical picture may be further complicated with the onset of ulcers, thromboembolic events, and cardiac failure [4] [5].

  • Intracranial AVFs

Typical symptoms of intracranial AVFs include a headache, ocular deficits, and neurological symptoms that are usually not significant. Some patients may remain asymptomatic.

A considerable number of patients presenting with pulmonary AVFs are also diagnosed with vascular anomalies in the nasopharynx, liver, spleen and gastrointestinal tract, as manifestations of the Rendu-Osler-Weber syndrome. Pulmonary arteriovenous fistulas per se may lead to dyspnea on exertion, symptoms related to high-output congestive heart failure, pulmonary hypertension, and hypoxemia [6] [7]. Compensatory polycythemia may develop, leading to non-specific symptoms, such as a headache and fatigue.

  • Spinal AVFs

They can lead to manifestations related to myelopathy.

These AVFs can be related to Rendu-Osler-Weber syndrome, Ehlers-Danlos syndrome, and biliary atresia.

  • Femoral AVFs

Patients frequently have varicosities. Symptoms associated with diminished perfusion of the limb can also arise.

Congestive Heart Failure
  • Pulmonary arteriovenous fistulas per se may lead to dyspnea on exertion, symptoms related to high-output congestive heart failure, pulmonary hypertension, and hypoxemia.[symptoma.com]
  • None of the patients developed symptomatic steal syndrome or congestive heart failure. Five of 6 patients had successful usage of the new AVF, and subsequently underwent ligation and excision of the aneurysmal AVF, thus avoiding a temporary HDC.[ncbi.nlm.nih.gov]
  • In general, given the high mortality secondary to severe congestive heart failure when treated conservatively, the goal of treatment in cortical AVF in young children, even when asymptomatic, is rapid control of the shunt.[ncbi.nlm.nih.gov]
  • The determination of these fistulas is very important because they tend to expand, while achieving a high flux at this level, can lead to the phenomena of congestive heart failure [ 8, 9 ].[ncbi.nlm.nih.gov]
Wound Infection
  • Incidence proportion of wound infection, hematoma, and dehiscence was higher in long incision group; however, it was statistically insignificant. Primary patency at 12 months in skip versus long incision group was 73.0% vs. 69.7% (P-value: 0.62).[ncbi.nlm.nih.gov]
Aspiration
  • Blood must be aspirated from the body of the patient, and since arteries are not easy to reach compared to the veins, blood may be aspirated from veins. The problem is that the walls of the veins are thin compared to those of the arteries.[en.wikipedia.org]
Abdominal Pain
  • Abstract BACKGROUND Splenic arteriovenous fistula (AVF) is a rare cause of portal hypertension which may manifest with abdominal pain, diarrhea, ascites, and/or hematemesis. Fistula formation may be traumatic or spontaneous.[ncbi.nlm.nih.gov]
Hypertension
  • The insertion of the cAV coupler resulted in a sustained anti-hypertensive effect nine months post-procedure, with mean 24-hr ABP of 154/91 mm Hg on only two anti-hypertensives.[ncbi.nlm.nih.gov]
  • Physicians should be aware of this pathology as an etiology of portal hypertension.[ncbi.nlm.nih.gov]
  • We therefore propose that venous engorgement and hypertension from central venous stenosis is the likely underlying cause for AVF-associated RAE.[ncbi.nlm.nih.gov]
  • Tumor can compromise the venous outflow, which can then lead to intracranial venous hypertension and development of the DAVF.[ncbi.nlm.nih.gov]
  • Such lesions reaching a size of more than 1 cm are termed as giant arachnoid granulations (GAGs) which have been previously reported to cause venous hypertension and headaches.[ncbi.nlm.nih.gov]
Vascular Disease
  • The controls were randomly selected from uremic patients who were primary AVF operation, excluded obvious vascular stenosis and vascular diseases. Among them, 4 sample in the experimental group and 4 controls were used in LncRNA sequencing.[ncbi.nlm.nih.gov]
  • Predictors for nonmaturation were female gender, peripheral vascular disease, cerebrovascular disease and a cephalic vein diameter CONCLUSION: Nonmaturation rates are highest for RCAVFs, but nonmaturation could not be predicted with demographic parameters[ncbi.nlm.nih.gov]
  • Arteriovenous fistula, abnormal direct opening between an artery and a vein ; it sometimes results from accidental penetration wounds or from vascular disease, or it may be congenital in origin.[britannica.com]
  • disease interventional cardiology A 62-year-old female underwent successful primary percutaneous coronary intervention for an acute anterior wall myocardial infarction via the right radial artery access.[heartasia.bmj.com]
  • The Dialysis Outcomes and Practice Patterns (DOPPS) III reports that patients were less likely to use an AVF if they were female, of older age, had a greater body mass index or had diabetes, peripheral vascular disease or recurrent cellulitis/gangrene[advancedrenaleducation.com]
Wide Pulse Pressure
  • The physical manifestations of this would be a relatively normal systolic blood pressure with a decreased diastolic blood pressure resulting in a wide pulse pressure.[en.wikipedia.org]
Decreased Diastolic Blood Pressure
  • The physical manifestations of this would be a relatively normal systolic blood pressure with a decreased diastolic blood pressure resulting in a wide pulse pressure.[en.wikipedia.org]
Wide Pulse Pressure
  • The physical manifestations of this would be a relatively normal systolic blood pressure with a decreased diastolic blood pressure resulting in a wide pulse pressure.[en.wikipedia.org]
Progressive Hearing Loss
  • CASE DESCRIPTION: A 60-year-old woman presented with a history of left progressive hearing loss and tinnitus for 1 year.[ncbi.nlm.nih.gov]
Urinary Retention
  • RESULTS: In our patient, symptoms progressed over 3 months from low back and radicular pain to weakness, saddle anesthesia, and urinary retention. MRI showed T2 hyperintensity from T3-4 to the conus medullaris.[ncbi.nlm.nih.gov]
Thalamic Pain
  • Two days later, his motor power deteriorated and he developed right hemisensory loss and severe thalamic pain. Aphasia was atypical and mimicked the transcortical type.[ncbi.nlm.nih.gov]
Tonic-Clonic Seizure
  • The patient presented with three episodes of generalised tonic-clonic seizures and improved with conservative treatment.[ncbi.nlm.nih.gov]
Generalized Seizure
  • CASE DESCRIPTIONS: A 73-year-old man presented with generalized seizure and reported severe but intermittent headache in the right temporo-occipital area. Single-photon emission computed tomography (SPECT) showed hyperperfusion in that area.[ncbi.nlm.nih.gov]

Workup

Radiological modalities employed in the diagnosis of arteriovenous fistulas are computed tomography (CT) angiography, magnetic resonance (MR) angiography, digital subtraction angiography (DSA), and color Doppler ultrasound.

CT angiography is a successful diagnostic procedure which produces accurate and specific findings. The modality reveals contrast material entering the vein prematurely during the arterial phase and illustrate the precise location of AVF. It has been found that CT angiography yields results that are in agreement with digital subtraction angiography [8]. The latter can provide particularly accurate information concerning the arteries involvement in the fistula formation and can help to create a diagram concerning the optimal therapeutic intervention.

Color Doppler ultrasound demonstrates blood flow patterns and velocity in the vessels. Frequent findings are an arterial-like wave in the adjacent vein and turbulent flow at the site of a connection. MRA is performed, in order to diagnose and clearly delineate the borders of AVFs [9] [10].

MR angiography could be performed in order to visualize AVFs more precisely [9] [10].

With regard to blood laboratory studies, patients affected by extensive AVFs may exhibit abnormal results such as thrombocytopenia, elevated PT and PTT time, decreased fibrinogen, and prolonged euglobulin clot lysis time.

Treatment

  • KEYWORDS: Treatment; arteriovenous fistula; endovascular; evolution; intraorbital; pure[ncbi.nlm.nih.gov]
  • Discussion about the need for treatment rises on individual basis. Based on the underlying etiology, a well-considered treatment plan should be made.[ncbi.nlm.nih.gov]
  • Despite current developments in medical technology and therapies, the effective treatment of critical PAVFs still poses a challenge. Therefore, more indications and effective alternative treatments must be discussed.[ncbi.nlm.nih.gov]
  • Other treatments, such as transarterial embolization, microsurgery or conservative treatment, can also be chosen. After appropriate treatment, most patients with lateral foramen magnum dural arteriovenous fistulas achieve satisfactory outcomes.[ncbi.nlm.nih.gov]
  • However, the endovascular treatment for type A lesions is technically challenging in view of near normal sized arterial feeders.[ncbi.nlm.nih.gov]

Prognosis

  • Angiosarcomas developing in nonfunctioning arteriovenous fistulas in renal transplant recipients are quite rare clinical entities with very poor prognosis.[ncbi.nlm.nih.gov]
  • In our experience, most children have an excellent prognosis.[childrenshospital.org]
  • Much of the presentation depends on the venous drainage pattern, which is the most important determinant of prognosis.[bmc.org]
  • BACKGROUND AND PURPOSE: The mechanisms and prognosis of underlying subarachnoid hemorrhage of unknown origin remain unclear.[ncbi.nlm.nih.gov]
  • KEYWORDS: Cavernous sinus dural arteriovenous fistula; angiographic features; fistulous point; prognosis; transvenous embolization[ncbi.nlm.nih.gov]

Etiology

  • Given the clinical symptoms, a workup was initiated to assess for a vascular etiology such as a dural arteriovenous fistula.[ncbi.nlm.nih.gov]
  • A spontaneous vertebral-venous fistula is rare, and the 2 cases presented illustrate an underlying spontaneous etiology. The first patient presented with a spontaneous fistula, and the second case occurred in a patient with neurofibromatosis type 1.[ncbi.nlm.nih.gov]
  • Physicians should be aware of this pathology as an etiology of portal hypertension.[ncbi.nlm.nih.gov]
  • Also the etiology, clinical manifestations, pathology, diagnosis, and management are summarized.[ncbi.nlm.nih.gov]
  • LESSONS: For patients who have been diagnosed with SAH but have no definite cause, we should pay attention to the etiological screening of SAH, and the possibility of the spinal cord SAH should be vigilant.[ncbi.nlm.nih.gov]

Epidemiology

  • B.M.Voorzaat@lumc.nl. 2 Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands. 3 Department of Surgery, Haaglanden Medical Center, The Hague, The Netherlands. 4 Department of Clinical Epidemiology, Leiden University Medical[ncbi.nlm.nih.gov]
  • Summary Epidemiology Prevalence is estimated at around 1/ 2,600. There is a minor female predominance.[orpha.net]
Sex distribution
Age distribution

Pathophysiology

  • Severe congestion of upper cerebellar veins seemed to be a possible pathophysiology of this specific bleeding pattern.[ncbi.nlm.nih.gov]
  • We present the first case of a dAVF with radiographic evidence of severe cortical venous reflux into the subependymal venous network causing isolated intraventricular hemorrhage, thus lending proof for the underlying pathophysiology.[ncbi.nlm.nih.gov]
  • The literature is reviewed, and potential pathophysiologic mechanisms leading to this association and regression in this subgroup of aneurysms are discussed.[ncbi.nlm.nih.gov]
  • However, the precise pathophysiology remains to be investigated.[ncbi.nlm.nih.gov]

Prevention

  • Early detection and surgical or endovascular intervention are important to preventing permanent neurologic impairment. Selective spinal angiography is still the gold standard for the diagnosis and localization of the SDAVF.[ncbi.nlm.nih.gov]
  • Transarterial n-butyl-2-cyanoacrylate embolization was performed to prevent rebleeding, and the pAVF was treated successfully. The patient's follow-up has been uneventful for 3 years.[ncbi.nlm.nih.gov]
  • Because an emergent mass reduction and prevention of rebleeding were necessary, single-session hematoma removal and transcranial embolization of a CS dAVF were performed in the neurosurgical operating room, using a mobile C-arm fluoroscopy.[ncbi.nlm.nih.gov]
  • To prevent from such a life-threatening event, the continuous blood pressure (BP) monitoring system may contribute to detect BP decline in early stages and may help to do appropriate disposal.[ncbi.nlm.nih.gov]
  • Abstract Peritoneal dialysis (PD) interruption requiring hemodialysis (HD) is not uncommon and its frequently abrupt nature prevents timely creation of permanent HD access and avoidance of central venous catheters (CVC).[ncbi.nlm.nih.gov]

References

Article

  1. Branham HH. Aneurysmal varix of the femoral artery and vein following a gunshot wound. Int J Surg.1890;3:250–251.
  2. Harrison's principles of internal medicine, 16th ed New York (NY): McGraw-Hill. 2005;1486–1494.
  3. Smith GE, Gohil R, Chetter I. Factors affecting the patency of arteriovenous fistulas for dialysis access. J Vasc Surg. 2011.
  4. Yakes WF, Krauth L, Ecklund J, et al. Ethanol endovascular management of brain arteriovenous malformations: initial results. Neurosurgery. 1997;40(6):1145-1154.
  5. Widlus DM, Murray RR, White RI Jr, et al. Congenital arteriovenous malformations: tailored embolotherapy. Radiology. 1988;169(2):511-516.
  6. Do YS, Kim YW, Park KB, et al. Endovascular treatment combined with emboloscleorotherapy for pelvic arteriovenous malformations. J Vasc Surg. 2011.
  7. Brinjikji W, Nasr DM, Morris JM, Rabinstein AA, Lanzino G. Clinical Outcomes of Patients with Delayed Diagnosis of Spinal Dural Arteriovenous Fistulas. AJNR Am J Neuroradiol. 2015.
  8. Biswas S, Chandran A, Radon M, et al. Accuracy of four-dimensional CT angiography in detection and characterisation of arteriovenous malformations and dural arteriovenous fistulas. Neuroradiol J. 2015.
  9. Pearce WH, Rutherford RB, Whitehill TA, et al. Nuclear magnetic resonance imaging: its diagnostic value in patients with congenital vascular malformations of the limbs. J Vasc Surg. 1988(1):64-70.
  10. Dobson MJ, Hartley RW, Ashleigh R, et al. MR angiography and MR imaging of symptomatic vascular malformations. Clin Radiol. 1997;52(8):595-602.

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Last updated: 2019-06-28 10:54