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Traumatic arteriovenous fistulae, resulting in delayed damage to the cervical spinal cord and roots, are well documented. This report concerns an iliac arteriovenous fistula with damage to the cauda equina.
Vertebral arteriovenous fistulas are rare. A report of two cases is presented with problems related to diagnosis and therapy. An alternative approach to surgical management is given.
Arteriovenous fistulae (AVF) between the femoral vessels were prepared in 20 rabbits to determine if local endovascular infections could be induced and if antibiotic prophylaxis could prevent infection. Twenty-four hours after bacterial challenge with 10(6) Staphylococcus aureus all 20 AVF were culture positive, whereas 19 of the 20 contralateral, unoperated femoral vessels were sterile. Two rabbits with AVF, followed for 30 days after receiving staphylocci, had intermittently positive blood cultures and had positive cultures of the AVF and heart valves at autopsy. Two groups of ten rabbits with AVF received either prophylactic oxacillin or vancomycin 0.5 h before bacterial challenge. Only 2 of 10 animals receiving oxacillin and 1 of 10 receiving vancomycin had positive AVF cultures at 24 h, a significant reduction in the incidence of endovascular infection compared with that in controls (P less than 0.001 by Fisher's exact test). This model, which reliably results in infection, can be used to study the pathophysiology, prevention, and treatment of AVF infections.
Three cases of arteriovenous fistulae observed in recent years at the University of Rome's 3rd Surgical Clinic, and of different site, entity are aetiology, are presented. The recent international literature is reviewed and the more outstanding clinical and therapeutical features of this form are discussed.
An iatrogenic renal arteriovenous fistula was treated by transcatheter embolization with particles of absorbable gelatin sponge. Recurrent massive hematuria was successfully controlled. The procedure was easily accomplished with minimal loss of renal parenchyma. Surgery, which usually requires partial or total nephrectomy, was avoided.
The correlation between the portal circulation and esophageal varices was evaluated in 80 patients with a primary carcinoma of the liver, with special regard being given to the significance of an hepatoportal arteriovenous fistula. Hepatoportal arteriovenous fistula was found in eight patients. Esophageal varices were observed 32 of all patients with a hepatoma. On the other hand, variceal lesions were found in 17 of 52 patients without compared with all patients with an hepatoportal arteriovenous fistula. A fatal hemorrhage was frequently encountered in the patients with the fistula. It was suggested that a rational treatment for those with the triple lesions--hepatoma, esophageal varices and hepatoportal arteriovenous fistula--may be ligation of the hepatic artery.
Arteriovenous fistula of the innominate artery occurred in a patient 3 weeks after retrograde brachial arterial catheterization was performed 1 day before aortocoronary bypass surgery. Intramural dissection was noted at catheterization, and a mediastinal hematoma at operation. Exploration of the hematoma in the course of catheterization might have prevented the arteriovenous fistula, which necessitated a second operation 3 weeks after the first. To our knowlege this complication of retrograde brachial catheterization has not previously been described. We recommend that known injuries to cervical or thoracic arteries occurring just before operations requiring extracorporeal circulation be explored to prevent late complications. Recent injuries to the cervical and thoracic arteries that are not acessible to external compression should be exposed and treated during sternotomy to prevent late complications if heparinization is contemplated.
Six bilateral loop arteriovenous fistulas from the femoral artery to the femoral vein were constructed in dogs using Dacron-mesh-coated human umbilical vein. Each graft was punctured twice weekly with a 16 gauge needle for up to 36 weeks, and biopsies were done every four to eight weeks. The long-term patency was 83% at 24 weeks. There was no thrombosis from the needle puncture. Serial histologic examination revealed progressive transmural fibrous cell ingrowth and progressive neointimal cell formation. Scanning electron microscopy demonstrated areas of disrupted basement membrane covered with laminar fibrin meshes, probably representing sites of needle puncture. With multiple attenuated internal reflection spectroscopy of the graft lumens, minimal to moderate lipid deposition was observed to a depth of 1 micrometer at 32-36 weeks. No abnormal amounts of minerals were found within the graft walls with energy-dispersive x-ray analysis. Critical surface tensions remained within the biocompatible range of 20-30 dynes/cm. Human umbilical vein possesses many of the surface chemistry qualities of an ideal vascular prosthesis, has excellent long term patency, and is suitable for use where angioaccess with repeated needle puncture is needed.
Arteriovenous fistulas commonly occur in cases of renal cell carcinoma, but they rarely produce sufficient left-to-right shunting to cause decompensation of the cardiovascular system. A case of refractory hypertension and congestive heart failure secondary to arteriovenous shunting in bilateral renal cell carcinoma is presented. Renal blood flow studies at the time of staged nephrectomy, together with measurements of cardiac output, established parenchymal arteriovenous shunting as the cause of the patient's cardiovascular symptoms. Subsequent nephrectomy achieved a marked clinical and symptomatic improvement. The causes, diagnosis, and treatment of arteriovenous fistulas are discussed. Although nephrectomy offers dramatic resolution of clinical symptoms, long-term survival depends on the behavior of the neoplasm.
Arteriovenous fistulae in renal allograft are rarely mentioned in papers dealing with vascular complications after renal transplantations. 2 cases of such central fistulae are reported. In our patients the fistulae remained asymptomatic and were incidentally detected, so that neither surgical nor medical measures had to be taken. Reviewing the rather scarce literature on this subject the etiology, symptomatology, prevention and therapy of these fistulae are discussed.
The clinical course of 100 internal arteriovenous fistulas in patients observed over a period of more than 6 months was analyzed. Ninety-six were practiced in the upper extremities as side-to-side anastomoses in the forearm between the radial artery and the nearest vein; three were constructed in the lower limbs as anastomoses between the femoral artery and the internal saphenous vein; and one was an autograft of the saphenous vein in the forearm. The most important complications observed were thrombosis (arising chiefly from scant venous development, surgical procedures, and episodes of arterial hypotension), distal ischemia, distal venous flow, infection of the fistula, and insufficient flow. A blood flow over 350 ml/min was achieved in all except two patients. The actuarial survival of individuals with arteriovenous fistulas is high at the present time, with 86 percent of the fistulas functioning after 3 years. The longest period of satisfactory arteriovenous fistula function is 8 years and 3 months.
A large renal arteriovenous fistula developed in a 71-year-old patient after percutaneous needle biopsy. Attempts to control the fistula with autologous clot were unsuccessful. A Fogarty catheter placed fluoroscopically was used to obliterate the feeding vessel. This is the first case reported in which this technique was used to control a renal arteriovenous fistula. This method of treatment offers the advantage of avoiding major surgical intervention with precise control of the fistula.
Arteriovenous fistula of the kidney is a common complication of percutaneous needle biopsy with a reported incidence of as high as 15% in some series. Although a few cases eventually may develop hypertension, cardiomegaly, or congestive heart failure, most heal spontaneously within 1-18 months. Those which do not heal within this time are usually treated surgically and consequently there is little available information concerning the long-term conservative management of this problem. The subject of this report is a patient who has been followed medically for 10 years and who, despite the persistence of a large fistula, remains in good health.
Malfunction of prosthetic arteriovenous fistulas is described in two patients, unheralded by abnormalities of arterial flow or venous resistance. In each case, significant graft recirculation due to stenosis of the venous limb caused the insidious onset of uremic symptoms in patients apparently receiving adequate hemodialysis. The uremic syndromes disappeared after correction of the faulty vascular access. Recirculation may be a "silent" cause of prosthetic graft malfunction which is promptly diagnosed by a simple mathematical formula. Routine estimates by a simple mathematical formula. Routine estimates of recirculation should be performed in any chronic hemodialysis patient with relapse of uremic symptoms or suspicious serum chemistries despite regular, uncomplicated hemodialysis. Patients found to have significant recirculation should be considered for angiography and graft replacement or revision.
Arteriovenous fistula (AVF) is the preferred vascular access for patients with end-stage renal disease; however, its failure is primarily due to neointimal hyperplasia. Five patients who underwent initial AVF surgery served as the control group, and another five patients with failed AVF surgery served as the experimental group. Herein, we employed mass spectrometry (MS)-based quantitative proteomics coupled with tandem mass tag labeling to screen differentially expressed proteins (DEPs) in the anastomotic cephalic vein, followed by bioinformatics analyses and verification experiments. A total of 121 DEPs were identified in the failed AVF group. GO analysis was primarily enriched in protein binding, nucleic acid binding, enzyme binding, mRNA binding, cadherin binding, catalytic activity, and cell adhesion molecule binding. KEGG pathways were mainly enriched in cell aggregation and adhesion, actin cytoskeleton, extracellular matrix-receptor interaction, PI3K-Akt signaling pathway, complement and coagulation cascades, and cholesterol metabolism. Protein-protein interaction network consisted of 86 (71.07%) DEPs, including complement VII (C7), factor IX (F9), SERPINC1, microfibril-associated glycoprotein 4 (MFAP4), complement C1s subcomponent, complement C1q subcomponent subunit A, complement C1q subcomponent subunit B, tissue factor, and von Willebrand factor, which interacting with numerous other proteins. In the expanded validation for different patients, C7, F9, SERPINC1, and MFAP4, were verified by immunohistochemical staining and Western blotting, which were consistent with the proteomics results. Collectively, this study identifies a series of potential diagnostic biomarkers, and explores the underlying mechanisms associated with AVF dysfunction.
Noninvasive diagnostic techniques permit objective assessment of the presence, location, and hemodynamic alterations associated with congenital or acquired arteriovenous fistulas. Doppler ultrasound may be used to assess abnormal velocity signals and directional blood flow in afferent and efferent limbs of the fistula, as well as abnormal pressure gradients in the involved extremity. Plethysmography permits graphic qualitative assessment of pulse wave form alterations before and after compression of the fistula. In addition, venous occlusion plethysmography permits quantitation of limb or digit blood flow before and after fistula. In addition, venous occlusion plethysmography permits quantitation of limb or digit blood flow before and after fistula compression. Illustrative cases of congenital and acquired arteriovenous fistulas demonstrate the utility of these noninvasive techniques in the objective assessment of patients.
Creation of an artificial subcutaneous arteriovenous fistula was attempted in five patients with malignant haematological disorders (two with Hodgkin's disease, two with acute lymphatic leukaemia, and one with acute myeloid leukaemia). The average time from the start of treatment to attempted creation of the fistulae was four years. Neither direct arteriovenous anastomosis nor an interposition mandril graft was successful in any patient. Failure was attributed to impaired venous run-off secondary to previous episodes of thrombophlebitis induced by the intravenous administration of cytotoxic drugs. The use of an arteriovenous fistula early in the course of the disease might minimize these later problems.
Two cases of pulmonary arteriovenous fistula were treated by local anatomical dissection and excision. This technique is preferable to pulmonary resection when the fistula is localised and superficially situated. The feeding vessels must be included in the resection to avoid possible recurrence. The history of the surgical removal of arteriovenous fistulae is discussed, and the reasons for preferring local excision are given.