Acute renal impairment due to a primary aortocaval fistula is normalised after a successful operation.
OBJECTIVES: To study renal function in patients with aortocaval fistula, before and after surgery. DESIGN: Retrospective study. MATERIAL AND METHODS: During the last 22 years nine male patients (median age 67, age range 50-72) with spontaneous aortocaval fistula in combination with AAA were operated upon. This constitutes 4% of the patients with ruptured AAA and 1.5% of all patients with AAA. RESULTS: A preoperative diagnosis of aortocaval fistula was established in three of the nine cases. The medium duration of symptoms prior to surgery was 5 days (range 4 h-14 days). The fistula was combined with an extravasating ruptured AAA in only three patients. Seven of the patients had acute renal insufficiency, with creatinine levels of in median 292 mumol (IQR 218-342). Creatinine declined to 172 mumol/l (IQR 170-313) on the fifth postoperative day in uncomplicated cases and to 86 mumol at discharge. One patient died due to multi-organ failure, whereas the other left hospital well and alive with normal renal function. CONCLUSION: Acute preoperative renal insufficiency due to an aortocaval fistula in patients with AAA is often due to venous congestion, and is normalised after successful surgery. (+info)
In vitro models of intracranial arteriovenous fistulas for the evaluation of new endovascular treatment materials.
BACKGROUND AND PURPOSE: The purpose of this study was to create and test an in vitro model of intracranial arteriovenous fistulas (AVFs) that simulates the geometry of human vasculature and allows realistic testing of devices used in endovascular therapy. METHODS: The models were derived from corrosion casts of the main cervicocranial arteries and veins obtained from two nonfixed human specimens. Wax copies of the casts were produced and combined to create complex models simulating various types of intracranial AVFs. Wax assemblies were embedded with liquid silicone solidified into transparent blocks containing, after wax evacuation, hollow reproductions of the original vascular trees. The models were connected to a pulsatile pump and their compatibility with various imaging techniques and endovascular treatment materials was evaluated. RESULTS: The models were compatible with digital subtraction angiography, CT, MR imaging, and transcranial Doppler sonography. They provided a realistic endovascular environment for the simulation of interventional neuroradiologic procedures. CONCLUSION: Anatomically accurate and reproducible in vitro models of intracranial AVFs provide a valuable method for evaluating new endovascular treatment materials and for teaching purposes. (+info)
Dural arteriovenous fistula of the cervical spine presenting with subarachnoid hemorrhage.
We describe a case of dural arteriovenous fistula (DAVF) presenting with subarachnoid hemorrhage (SAH). The diagnosis of DAVF was based on spinal angiography. A review of the literature revealed that five of 13 previously reported DAVFs of the cervical spine were accompanied by SAH. SAH has not been observed in DAVFs involving other segments of the spinal canal. (+info)
Atypical pulmonary artery sling with diffuse-type pulmonary arteriovenous fistula.
The case of a cyanotic infant with a rare combination of atypical pulmonary artery sling, imperforate anus, absence of the left kidney, interruption of the inferior vena cava, left side hemihypertrophy and diffuse-type pulmonary arteriovenous fistula is described. The clinical features were confusing, because of compounding abnormalities involving the respiratory tract and pulmonary circulation. The diagnostic approach to the etiology of cyanosis is discussed and the embryonic origin of pulmonary artery sling is reviewed. (+info)
Early prenatal diagnosis of cord entanglement in monoamniotic multiple pregnancies.
OBJECTIVES: Cord entanglement is a severe complication in monoamniotic multiple pregnancies. Three cases were reviewed to determine how early ultrasound diagnosis might improve counselling and management. METHODS: In two monoamniotic twin and one dichorionic diamniotic triplet pregnancies, cord entanglement was detected between 10 and 18 gestational weeks by color Doppler and pulsed Doppler velocimetry. Pregnancies were followed up on a weekly basis with special observation of fetal behavior and use of color Doppler velocimetry. RESULTS: In Case 1, a monoamniotic twin pregnancy with cord entanglement close to the umbilical insertions was diagnosed at 10 weeks. Longitudinal follow-up showed intrauterine death of both twins at 15 weeks. In Case 2, entanglement of the umbilical cords of two monoamniotic triplets within a dichorionic diamniotic triplet pregnancy was diagnosed at 10 weeks. The pregnancy continued uneventfully until 35 weeks when cord entanglement was confirmed at Cesarean section. All triplets have since developed normally. In Case 3, monoamniotic twins were diagnosed at 18 weeks. Color Doppler detected side-by-side insertion of the umbilical cords and Doppler velocimetry suggested an entanglement at the chorionic plate. The pregnancy was complicated by polyhydramnios. Cesarean section at 36 weeks confirmed cord entanglement at the chorionic plate. Postnatal computer angiography and morphological examination of the placenta showed the presence of superficial artery-to-artery and vein-to-vein anastomoses and of deep arteriovenous shunts. The development of the twins was uneventful. CONCLUSIONS: Diagnosis of cord entanglement is feasible early in gestation. Future protocols are proposed to document the gestational age at detection, the location, and the Doppler flow patterns and to facilitate the assessment of short- and long-term development. (+info)
Multiple dural arteriovenous shunts in a 5-year-old boy.
We describe a rare case of multiple dural arteriovenous shunts (DAVSs) in a 5-year-old boy. MR imaging performed at 1 year of age showed only a dilated anterior part of the superior sagittal sinus; however, angiography at 5 years of age revealed an infantile-type DAVS there and two other DAVSs of the adult type. The pathophysiological evolution of DAVSs in children and their treatment strategies are discussed. (+info)
3D Ultrasound imaging--a useful non-invasive tool to detect AV fistulas in transplanted kidneys.
BACKGROUND: A precise, non-invasive, non-toxic, repeatable, convenient and inexpensive follow-up of renal transplants, especially following biopsies, is in the interest of nephrologists. Formerly, the rate of biopsies leading to AV fistulas had been underestimated. Imaging procedures suited to a detailed judgement of these vascular malformations are to be assessed. METHODS: Three-dimensional (3D) reconstruction techniques of ultrasound flow-directed and non-flow-directed energy mode pictures were compared with a standard procedure, gadolinium-enhanced nuclear magnetic resonance imaging angiography (MRA) using the phase contrast technique. RESULTS: Using B-mode and conventional duplex information, AV fistulas were localized in the upper pole of the kidney transplant of the index patient. The 3D reconstruction provided information about the exact localization and orientation of the fistula in relation to other vascular structures, and the flow along the fistula. The MRA provided localization and orientation information, but less functional information. Flow-directed and non-flow-directed energy mode pictures could be reconstructed to provide 3D information about vascular malformations in transplanted kidneys. CONCLUSION: In transplanted kidneys, 3D-ultrasound angiography may be equally as effective as MRA in localizing and identifying AV malformations. Advantages of the ultrasound method are that it is cheaper, non-toxic, non-invasive, more widely availability and that it even provides more functional information. Future prospective studies will be necessary to evaluate the two techniques further. (+info)
Aortocaval fistula in ruptured aneurysms.
OBJECTIVES: to study incidence, clinical presentation and problems in management of aortocaval fistula in our series. DESIGN: retrospective study. MATERIALS: during a seven-year period, 112 patients operated on for abdominal aortic aneurysm, including four patients with aortocaval fistula. METHODS: standard repair of aortocaval fistula from inside the aneurysmal sac was the preferred operative technique. RESULTS: the incidence of aortocaval fistula was 3.6%. Three cases were found incidentally during emergency surgery for ruptured aneurysms; the fourth case was an isolated aortocaval fistula associated with inferior vena cava thrombosis, diagnosed preoperatively by angiography. In this case, inferior vena cava ligation instead of standard aortocaval repair was performed. CONCLUSIONS: Aortocaval fistulas, although rare, should be kept in mind, because clinical diagnosis is often difficult. Furthermore, unsuspected problems during repair may necessitate appropriate change in operative technique. (+info)