Arteriovenous malformation in a rhesus monkey (Macaca mulatta)

A developmental arteriovenous malformation of the right arm was recognized in a 1-year-old rhesus monkey. The diagnosis was based on physical findings, ultrasound, and angiography. Treatment consisting of therapeutic transcatheter embolization using polyvinyl alcohol was performed with partial success. Necropsy revealed a lesion that was limited to the skin and subcutis. An abnormal vascular pattern was present leading to and within the lesion.     

SUCCESSFUL SURGICAL MANAGEMENT OF CONGENITAL ARTERIOVENOUS FISTULA OF THE SUBCLAVIAN ARTERY: CASE REPORT

A 10-month-old infant was found to have an isolated congenital arteriovenous fistula between the right subclavian artery and vein. Ligation of the fistula resulted in complete anatomic correction and rapid resolution of cardiomegaly.     

Arteriovenous fistula after intervertebral disk surgery at L4-L5

We describe a 34-year-old woman who had symptoms of heart failure due to an arteriovenous fistula between the right iliac artery and the inferior vena cava caused by surgery for a herniated intervertebral disk. The literature is reviewed. An intra-arterial placed covered stent was successfully used to close the fistula.     

Arteriovenous fistulas after replantation surgery

The delayed appearance of congenital arteriovenous fistula precipitated by local trauma is a rare event. However, these reports may provide some insight into pathogenetic mechanisms responsible for the opening of subclinical arteriovenous communications. This case of multiple arteriovenous fistulas in a previously "normal" hand followed a sharp, incomplete amputation at the wrist level with replantation.     

Systemic arteriovenous fistula leads to pulmonary artery remodeling and abnormal vasoreactivity in the fetal lamb

Several cases of systemic arteriovenous fistula diagnosed in the human fetus have been associated with the postnatal development of persistent pulmonary hypertension. The aim of this study was to determine the effects of a prenatally created systemic arteriovenous fistula on the structure and reactivity of the pulmonary circulation in the fetal lamb. A fistula between the jugular vein and carotid artery was created in fetal lambs at 119-124 days of gestation. At delivery (134-139 days), left pulmonary artery (LPA) pressure was increased in the fistula group (n = 12) compared with controls (n = 11, P < 0.01). The pulmonary vascular resistance was significantly higher in the fistula group (P < 0.05), whereas mean LPA blood flow was not statistically different between the two groups. Morphometric analysis of the pulmonary vascular bed revealed an increase in the number of peripheral muscular arteries, together with an increase in pulmonary arterial medial thickness in the fistula group. There was no difference in the relative number or size of intraacinar arteries. In vitro organ bath studies on pulmonary arterial rings showed impaired endothelium-dependent relaxation in the fistula group compared with controls. However, endothelial nitric oxide synthase protein expression was similar in both groups, whereas endothelium-independent relaxation to sodium nitroprusside was greater in the fistula group compared with controls. A systemic arteriovenous fistula leads to both structural and functional alteration of the pulmonary vasculature, which might lead to the development of persistent pulmonary hypertension after birth.     

New capillary bed formation with a surgically constructed arteriovenous fistula

This study on 24 rats has demonstrated that neovascularization of the skin through an arteriovenous fistula is possible. A vascular bed can be created by the use of long interpositional vein grafts. An arteriovenous fistula in the shape of a loop could not only provide vascularity to create a skin flap of unlimited size but could possibly vascularize a digital replantation with severely damaged vessels and provide enough additional vascularity to facilitate the take of bone grafts and tissue composites.     

Direct effects of nitroprusside do not alter gas exchange in canine oleic acid edema

The authors investigated why intrapulmonary shunt (QS/QT) increases with sodium nitroprusside (SNP) in canine oleic acid pulmonary edema. To determine the effects of flow alone on QS/QT, a peripheral arteriovenous fistula with a variable resistor was employed to increase cardiac output (Q) 26 and 52% above base line in a stepwise fashion (P less than 0.01). To examine the direct effects of SNP, distinct from changes in flow, the drug was given to produce matched increments in Q in each dog (P less than 0.01). To control for time, base-line measurements were obtained before and after each intervention, the sequence of which was alternated. At each increment in Q, SNP and the arteriovenous fistula increased QS/QT a similar amount. The mixed venous O2 tension (P-vO2) followed Q similarly in each group. Pulmonary vascular resistance (PVR) fell more (P less than 0.01) with SNP than with the arteriovenous fistula at identical Q and P-vO2. The authors conclude that, in this model, a direct pharmacological effect of SNP does not contribute to the deterioration in QS/QT. In fact, SNP exerts a pulmonary vasoactive effect that does not adversely affect gas exchange.     

Cutaneous zygomycosis caused byAbsidia corymbifera in a leukemic patient

A case of cutaneous zygomycosis caused byAbsidia coryabifera in a leukemic patient submitted to chemotherapy is reported. The lesion was located on the little finger of the right hand and probably resulted from a latent osteomyelitis. It progressed to form extensive necrotic area. No systemic infection was detected and the lesion did not appear to be associated with any trauma.     

Use of Internal Arteriovenous Fistula in Home Haemodialysis

Five patients with previous experience of home haemodialysis (lasting one to two years) had internal arteriovenous fistulae created in a previously non-cannulated limb. After training of the spouses or patients to insert the needles, the arteriovenous cannulas were removed and the patients maintained on fistula dialysis in the home, unattended, overnight, for periods of 1 to 11 months (total patient experience of 30 months). All patients expressed a preference for the arteriovenous fistula, and no significant medical complications have been noted to date.The safe use of a blood pump in the home, overnight, was achieved by the addition of an extra monitor on the outflow (arterial) blood line.     

UNILATERAL PARALYSIS OF EYE MUSCLES ASSOCIATED WITH INTRACRANIAL SACCULAR ANEURYSMS

Unexplained unilateral paralysis of eye muscles with or without evidence of altered function of other cranial nerves, or of the presence of intracranial bruit, is strong positive diagnostic evidence of saccular aneurysm of the intracranial internal carotid or of the circle of Willis. If pulsating exophthalmos is present the lesion probably is an arteriovenous fistula.The presence of such clinical signs strongly indicates the desirability of cerebral angiography. Once demonstrated, the lesion can usually be treated successfully by ligation of the contributing vascular connections.     

TRAUMATIC ARTERIOVENOUS COMMUNICATION PRESENTING 36 YEARS AFTER INITIAL INJURY

A 59-year-old man who had sustained multiple pelvic fractures 36 years ago recently developed progressive neurological deficits. His symptoms suggested an arteriovenous (AV) malformation of the spinal cord. This report details the steps taken in locating the fistula angiographically and in performing a preliminary temporary obliteration using an intra-arterial catheter balloon. After appropriate studies were carried out, the fistula was successfully excised. Immediate improvement in the peripheral circulation resulted, along with progressive ablation of the neurological deficits. A review of the literature has not revealed a similar case.     

Distal arteriovenous fistula to maintain patency of the venous drainage of a latissimus dorsi flap following subclavian vein repair

Successful reconstructive surgery with muscle flaps depends on adequate arterial supply and undisturbed venous drainage. Combining such surgery with reconstructive vascular surgery of a large-caliber vein that is responsible for the venous drainage of the flap poses an additional challenge--the repaired vein's susceptibility to thrombosis. Every attempt must be made to prevent venous outflow obstruction following muscle flap surgery. Data from the vascular surgery literature demonstrate a low success rate for subclavian vein repair. The success rate with venous reconstructive surgery has been greater when a distal arteriovenous fistula accompanied the repair. The present case described the use of a temporary distal cephalic-brachial arteriovenous fistula to maintain the patency of the venous drainage of a pedicled latissimus dorsi muscle flap, following subclavian vein repair, for one-stage coverage of a large chest wall defect.     

Diagnostic difficulties in differentiating of arteriovenous fistula -- case report

Arteriovenous carotid-cavernous fistula is an abnormal connection between the dural branches of carotid artery or vertebral artery and the dural sinuses. Its clinical manifestations can resemble the crucial signs of thyroid orbitopathy, an inflammatory disorder of the orbit associated with Graves' disease. Therefore, differential diagnosis of thyroid orbitopathy and the congestion of the orbit seen in arteriovenous fistula is often clinically and radiologically confused. This is the case report of the simultaneous occurrence of dural arteriovenous fistula in 59 years old woman. The first manifestation was unilateral exophthalmia. After Computer Tomography and Magnetic Resonance Imaging were performed, the preliminary diagnosis of thyroid orbitopathy was established. The response of eye disorder to corticosteroid treatment resulted in evident deterioration. This prompted a reconsideration of the diagnosis and a new evaluation of the patient with sensitive techniques, leading to the final diagnosis of arteriovenous fistula.     

Synchronous mucinous adenocarcinoma of the rectosigmoid seeding onto a pre-existing anal fistula

Carcinoma within a long-standing fistula-in-ano is rare and may be defined by specific neoplastic involvement of the fistulous track in the absence of rectal mucosal carcinoma. The presence of a carcinoma of mucinous histology occurring synchronously in the perianal region and the colon is exceptionally rare. We present a case with a review of the literature concerning its aetiopathogenesis and treatment. A 72-year-old man with a 2 months history of dark red rectal bleeding and mucus per rectum with alternating constipation and diarrhoea, was observed. Clinical examination and a barium enema showed a perianal fistula and an annular stenosing lesion of the rectosigmoid. Preoperative CT scan confirmed the colonic lesion. Colonic resection and wide fistula excision were performed. Histology showed an adenocarcinoma with a clear resection margins. The fistula also showed a similar histology. Chemoradiation (5-Fluorouracil (425 mg/m²) and Leucovorin (20 mg/m²) with 4500 cGy external beam radiotherapy was utilized. Subsequent clinical follow-up and CT examination of the patient has not revealed recurrent disease at 14 months.     

彩色多普勒超声在血液透析动静脉内瘘功能评估及病变检测中的应用探究

目的:探讨彩色多普勒超声在血液透析动静脉内瘘功能评估及病变检测中的应用价值。方法:选取2013年3月至2016年3月于我院接受血液透析的终末期肾病患者62例作为研究对象,采用二维超声观察动静脉内瘘的一般情况,采用彩色多普勒观察血流方向、速度以及充盈情况,对检测结果进行比较。结果:自体动静脉内瘘成形术后桡动脉管径(RAD)、桡动脉血流量(RVF)、头静脉管径(CVD)均较术前有所提高,各项指标随时间延长而逐渐增高,差异有统计学意义(P0.05)。62例血液透析患者中,共有41例(66.13%)患者动静脉内瘘通畅,21例(33.87%)患者出现动静脉内瘘并发症,其中血栓形成9例(14.52%)、动静脉瘘狭窄7例(11.29%)以及静脉瘤状扩张5例(4.84%)。血栓形成组头静脉血管内径(D)、吻合口D、最大峰值流速(PSV)及血流阻力指数(RI)、桡动脉D、PSV及RI均较正常组有显著差异。血栓形成、动静脉瘘狭窄患者上述参数及血流量与正常组比较有显著差异(P0.05)。结论:彩色多普勒超声可有效监测血液透析患者动静脉内瘘病变发生情况,对其结构功能进行直接观察的同时还可明确诊断动静脉内瘘并发症。     

Adenosine: a novel ulcer modulator in stomachs.

Adenosine has been demonstrated for its actions on gastric secretion and stress-induced gastric ulceration in animals. We examined the pharmacological actions of adenosine on ethanol-evoked gastric lesions and gastric mucosal blood flow (GMBF) in rats, because both of them are closely related. Adenosine pretreatment, in dose of 7.5 mg/kg increased GMBF and protected against ethanol-evoked gastric lesion formation. However, this antiulcer action was followed by an aggravation of gastric lesions and reduction in GMBF. We further investigated whether these actions could act through the adenosine A1 or A2 receptors, therefore L-phenylisopropyladenosine (L-PIA) or N-ethylcarboxamidoadenosine (NECA), the adenosine A1 or A2 receptor agonists, respectively, were used. The drugs given in doses of 10 or 50 micrograms/kg for L-PIA and 1 or 5 micrograms/kg for NECA, dose-dependently inhibited GMBF and potentiated ethanol-induced gastric damage. When the two drugs were given together to animals, they did not further aggravate the severity of ulceration and reduction of GMBF. These findings indicate that the antiulcer action of adenosine is not mediated via the adenosine A1 and A2 receptors but if acts through different adenosine receptor subtypes. It was because the lesion worsening effects of adenosine at the second stage of the biphasic responses were similar to the actions of L-PIA and NECA, the ulcer potentiating effect is probably acting through adenosine A1 and A2 receptors in anaesthetised rats.     

Monophasic synovial sarcoma presenting as a primary ileal mass: a case report and review of the literature

Introduction

Iliocaval fistulas can complicate an iliac artery aneurysm. The clinical presentation is classically a triad of hypotension, a pulsatile mass and heart failure. In this instance, following presentation with multiorgan failure, management included the immediate use of an endovascular stent graft on discovery of the fistula.

Case presentation

A 62-year-old Caucasian man presented to our tertiary hospital for management of iatrogenic trauma due to the insertion of a central venous line into his right common carotid artery, causing transient ischemic attack. Our patient presented to a peripheral hospital with fever, nausea, vomiting, acute renal failure, acute hepatic dysfunction and congestive heart failure. A provisional diagnosis of sepsis of unknown origin was made. There was a 6.5 cm×6.5 cm right iliac artery aneurysm present on a non-contrast computed tomography scan. An unexpected intra-operative diagnosis of an iliocaval fistula was made following the successful angiographic removal of the central line to his right common carotid artery. Closure of the iliocaval fistula and repair of the iliac aneurysm using a three-piece endovascular aortic stent graft was then undertaken as part of the same procedure. This was an unexpected presentation of an iliocaval fistula.

Conclusion

Our case demonstrates that endovascular repair of a large iliac artery aneurysm associated with a caval fistula is safe and effective and can be performed at the time of the diagnostic angiography. The presentation of an iliocaval fistula in this case was unusual which made the diagnosis difficult and unexpected at the time of surgery. The benefit of immediate repair, despite hemodynamic instability during anesthesia, is clear. Our patient had two coronary angiograms through his right femoral artery decades ago. Unusual iatrogenic causes of iliocaval fistulas secondary to previous coronary angiograms with wire and/or catheter manipulation should be considered in patients such as ours.     

UNUSUAL CASE OF PULMONARY ARTERIOVENOUS FISTULA CONCEALED BY THE CARDIAC SILHOUETTE ON CHEST ROENTGENOGRAM

A large pulmonary arteriovenous fistula was discovered in a patient with long-standing cyanosis, clubbing and dyspnea, with no other cardiovascular signs or symptoms and a normal chest roentgenogram at the time of cardiac catheterization and pulmonary angiography. The fistula was overshadowed by the cardiac silhouette. Surgical resection was successful. Although rarely undetected on the chest roentgenogram, this potentially lethal malformation should be considered in the differential diagnosis of cyanosis unaccompanied by other cardiovascular signs or symptoms.     

高频彩色多普勒超声监测维持性血透内瘘功能的临床应用现状

该文综述了应用高频彩色多普勒超声在血透患者动静脉内瘘（ AVF）术前进行目标血管的选择,检查、筛选与定位,术后可用于监测动静脉内瘘（ AVF）功能、流量、流速与各种并发症,以利于提高血透患者的生活质量与生存率。     

Cytodiagnosis of hydatid disease presenting with Horner's syndrome: a case report

BACKGROUND: The diagnosis of echinococcosis is based on clinical, radiologic and serologic findings. Fine needle aspiration (FNA) is useful in evaluating the lesion when the presentation is atypical. We report a case of hydatid cyst at the lung apex in which the diagnosis was made on FNA, with no adverse reaction to the aspiration. CASE: A 30-year-old male, a chronic smoker, presented with pain radiating to the medial two fingers of the right hand for two years. He also had miosis and ptosis of the right eye and anhidrosis of the right side of theface. There was wasting of small muscles in the right hand. Magnetic resonance imaging revealed a hyperintense mass at the apex of the right lung, thoracic inlet and adjacent vertebral bodies. A clinical diagnosis of Horner's syndrome due to pancoast tumor was rendered. Ultrasound-guided FNA showed protoscolices, scattered hooklets and bits of acellular laminated membrane, characteristic of echinococcosis. Surgical excision of the cyst was done. Gross and histopathologic examination of the excised cyst confirmed the diagnosis. CONCLUSION: FNA, though traditionally contraindicated, is a highly desirable, rapid, noninvasive diagnostic mode for echinococcosis. In view of its pathognomonic cytomorphologic features and numerous reports on cytodiagnosis in the literature, it is time to evaluate the diagnostic benefits and weigh the risks against the advantages of the technique.