Renal arteriovenous fistula associated with a huge renal vein dilatation

Successful surgical treatment with ex vivo technique in a patient with renal artery aneurysm rupture and bilateral arteriovenous fistula

Renal arteriovenous fistulas are pathologic communications between the renal arteries and veins without interconnecting capillaries. Reports on the combination of fibromuscular dysplasia, aneurysms, and renal arteriovenous fistula are extremely rare in the literature. In the case of renal arteriovenous aneurysm rupture, urgent nephrectomy was the only life-saving procedure reported. The ex vivo approach seems to be an appropriate alternative to nephrectomy. This article presents a case of successful treatment of bilateral fibromuscular dysplasia with aneurysm and arteriovenous fistulas complicated by renal artery aneurysm rupture.

Aneurysm of the right renal vein arising from an idiopathic arteriovenous fistula

A renal vein aneurysm is rarely secondary to an arteriovenous fistula. A symptomatic 4.7-cm aneurysm of the right renal vein arising from an idiopathic arteriovenous fistula in a 41-year-old woman is described. Imaging techniques have a critical role in planning the treatment. The 4.7-cm aneurysm showed a venous wall with uneven thickening of the intima, irregular atrophy and architectural disarray of the media, and partial loss of elastic fibers. Potential for rupture supports surgical intervention in a selected patient with a macroaneurysm.

Perirenal venous aneurysm presenting as retroperitoneal tumor treated successfully by laparoscopic excision

We describe an unusually located venous aneurysm found incidentally in a 46-year-old man that was presumptively diagnosed as a retroperitoneal mass near the left renal hilum. He presented for constipation and weight loss; an abdominal ultrasound scan disclosed an anechoic lesion in the left retroperitoneum. Abdominal CT showed a 3-cm mass with low density located at the junction of the left para-aortic and perirenal hilar regions that was initially suspected of being metastatic lymphadenopathy with an unknown primary origin or a neurogenic tumor. The mass was resected by a laparoscopic approach, which revealed a round mass with a smooth capsule and roots connecting to the paraspinal muscles. On pathologic examination, the mass showed classic features of a venous aneurysm. At 12-month follow-up, no local recurrence or malignancy was documented.

Erosion of embolization coils and guidewires from the kidney to the colon: delayed complication from coil and guidewire occlusion of renal arteriovenous malformation

Percutaneous transarterial embolization is a useful, nondrastic, valuable, and commonly used therapeutic option for the treatment of renal arteriovenous malformation (AVM). Compared with partial or total nephrectomy, transarterial embolization is more conservative and preserves renal function. However, it has some limitations and complications that could cause renal infarction and progression of hypertension, renal insufficiency, and pulmonary embolism. Large-sized AVM and multiplicity of abnormal vessels also limit the use of the embolization technique. The authors experienced erosion of the coils and guidewires that were used for embolization of renal AVM from kidney to descending colon. Coil embolization is practiced extensively, but a complication such as this does not appear to have been described.

Staged endovascular occlusion of giant idiopathic renal arteriovenous fistula with platinum microcoils and silk suture threads

Large symptomatic aneurysmal renal arteriovenous (AV) fistulas usually present with a flank bruit, uncontrolled hypertension, and high-output cardiac failure. Traditionally, these have been treated surgically because of the risk of inadvertent pulmonary embolism with use of embolization techniques. The authors report a case of a giant renal AV fistula successfully treated with staged embolization with use of metallic coils and silk suture. This resulted in a graded reduction in the extreme flow through the fistula, followed by delayed thrombosis and cure of the patient's symptoms.

Usefulness of dynamic renal scintigraphy in a patient with renal arteriovenous fistula treated by transcatheter embolization

Tc-99m-DTPA renal scintigraphy was performed before and after transcatheter coil embolization in a patient with renal arteriovenous fistula (AVF). Before embolization, scintigraphy showed a characteristic accumulation pattern compatible with the hemodynamics of an aneurysmal type of AVF in the vascular phase. After embolization, the effects of treatment, such as a change in the split renal function on the treated-side and the disappearance of the shunt flow through the fistula were evident. It was concluded that dynamic renal scintigraphy was very useful for patients with an aneurysmal type of renal AVF scheduled for transcatheter embolization.

Symptomatic solitary right renal vein aneurysm: a case report

Renal vein aneurysms are very uncommon. Those located in the right side are exceptional. A symptomatic, solitary, voluminous aneurysm of the right renal vein in a 33-year-old man is reported. The lesion was diagnosed preoperatively as a renal tumor. The pathologic study of the nephrectomy specimen disclosed a thrombosed saccular aneurysm measuring 5.5 cm with marked medial atrophy of its wall. Recognition that a mass like this reported is of vascular origin is very important to avoid percutaneous biopsy which could be potentially hazardous; and for undertaking conservative prophylactic surgery. Renal venography is indicated for the diagnosis of these lesions.

Transcatheter embolization of large idiopathic renal arteriovenous fistula

Renal arteriovenous fistulas are unusual lesions with a variety of clinical manifestations. Congenital and acquired forms have been treated successfully with transcatheter embolization for 2 decades. In the case of large aneurysmal lesions the risk of inadvertent pulmonary embolism has traditionally precluded this approach and necessitated open surgery. However, with refinements in angiographic equipment and technique, such an approach is now feasible and desirable.

Recent advances in the diagnosis and treatment of renal arteriovenous malformations and fistulas

Arteriovenous malformations remain relatively rare clinical lesions. However, with an increasing number of percutaneous renal procedures being performed, their overall incidence can be expected to increase. Congenital arteriovenous malformations usually present with hematuria, while acquired fistulas are more likely to present with hemodynamic changes, such as hypertension, cardiomegaly and congestive heart failure. Arteriography remains the principal method of diagnosis. However, newer imaging modalities such as CT, MRI and color duplex ultrasound may make significant contributions in the evaluation of these abnormalities (fig. 1). Surgery, whether nephrectomy or ligation of feeding vessels, has long been the standard treatment for symptomatic arteriovenous malformations or fistulas. The loss of normal renal parenchyma, migration of occluding agents or recanalization of abnormal vessels has limited the use of embolization as a method of treatment in the past. Recently, newer techniques and agents, such as pharmacoangiography and alcohol, have increased the efficacy of embolization therapy, either as an adjuvant to surgery, definitive therapy or palliation. Although to our knowledge there have been no controlled studies comparing surgical treatment versus embolization, certain recommendations can be made. Because of the decreasing morbidity and increasing efficacy, embolization should be attempted at the time of arteriography as a means of treatment for most arteriovenous malformations and fistulas. However, the choice of surgery, embolization or a combination must be individualized for each patient with regard to overall health, symptoms and manifestations of the fistula or malformation (fig. 2).