Endovascular treatment of renal artery aneurysms with conventional non-detachable microcoils and Guglielmi detachable coils

Beyond Atherosclerosis and Fibromuscular Dysplasia: Rare Causes of Renovascular Hypertension

Renovascular hypertension is one of the most common forms of secondary hypertension. Over 95% of cases of renovascular hypertension are due either to atherosclerosis of the main renal artery trunks or to fibromuscular dysplasia. These two causes of renal artery stenosis have been extensively discussed in recent reviews and consensus. The aim of the current article is to provide comprehensive and up-to-date information on the remaining causes. While these causes are rare or extremely rare, etiologic and differential diagnosis matters both for prognosis and management. Therefore, the clinician cannot ignore them. For didactic reasons, we have grouped these different entities into stenotic lesions (neurofibromatosis type 1 and other rare syndromes, dissection, arteritis, and segmental arterial mediolysis) often associated with aortic coarctation and other arterial abnormalities, and nonstenotic lesions, where hypertension is secondary to compression of adjacent arteries and changes in arterial pulsatility (aneurysm) or to the formation of a shunt, leading to kidney ischemia (arteriovenous fistula). Finally, thrombotic disorders of the renal artery may also be responsible for renovascular hypertension. Although thrombotic/embolic lesions do not represent primary vessel wall disease, they are characterized by frequent macrovascular involvement. In this review, we illustrate the most characteristic aspects of these different entities responsible for renovascular hypertension and discuss their prevalence, pathophysiology, clinical presentation, management, and prognosis.

Beyond Atherosclerosis and Fibromuscular Dysplasia: Rare Causes of Renovascular Hypertension

Renovascular hypertension is one of the most common forms of secondary hypertension. Over 95% of cases of renovascular hypertension are due either to atherosclerosis of the main renal artery trunks or to fibromuscular dysplasia. These two causes of renal artery stenosis have been extensively discussed in recent reviews and consensus. The aim of the current article is to provide comprehensive and up-to-date information on the remaining causes. While these causes are rare or extremely rare, etiologic and differential diagnosis matters both for prognosis and management. Therefore, the clinician cannot ignore them. For didactic reasons, we have grouped these different entities into stenotic lesions (neurofibromatosis type 1 and other rare syndromes, dissection, arteritis, and segmental arterial mediolysis) often associated with aortic coarctation and other arterial abnormalities, and nonstenotic lesions, where hypertension is secondary to compression of adjacent arteries and changes in arterial pulsatility (aneurysm) or to the formation of a shunt, leading to kidney ischemia (arteriovenous fistula). Finally, thrombotic disorders of the renal artery may also be responsible for renovascular hypertension. Although thrombotic/embolic lesions do not represent primary vessel wall disease, they are characterized by frequent macrovascular involvement. In this review, we illustrate the most characteristic aspects of these different entities responsible for renovascular hypertension and discuss their prevalence, pathophysiology, clinical presentation, management, and prognosis.

Beyond Atherosclerosis and Fibromuscular Dysplasia: Rare Causes of Renovascular Hypertension

Renovascular hypertension is one of the most common forms of secondary hypertension. Over 95% of cases of renovascular hypertension are due either to atherosclerosis of the main renal artery trunks or to fibromuscular dysplasia. These two causes of renal artery stenosis have been extensively discussed in recent reviews and consensus. The aim of the current article is to provide comprehensive and up-to-date information on the remaining causes. While these causes are rare or extremely rare, etiologic and differential diagnosis matters both for prognosis and management. Therefore, the clinician cannot ignore them. For didactic reasons, we have grouped these different entities into stenotic lesions (neurofibromatosis type 1 and other rare syndromes, dissection, arteritis, and segmental arterial mediolysis) often associated with aortic coarctation and other arterial abnormalities, and nonstenotic lesions, where hypertension is secondary to compression of adjacent arteries and changes in arterial pulsatility (aneurysm) or to the formation of a shunt, leading to kidney ischemia (arteriovenous fistula). Finally, thrombotic disorders of the renal artery may also be responsible for renovascular hypertension. Although thrombotic/embolic lesions do not represent primary vessel wall disease, they are characterized by frequent macrovascular involvement. In this review, we illustrate the most characteristic aspects of these different entities responsible for renovascular hypertension and discuss their prevalence, pathophysiology, clinical presentation, management, and prognosis.

Beyond Atherosclerosis and Fibromuscular Dysplasia: Rare Causes of Renovascular Hypertension

Renovascular hypertension is one of the most common forms of secondary hypertension. Over 95% of cases of renovascular hypertension are due either to atherosclerosis of the main renal artery trunks or to fibromuscular dysplasia. These two causes of renal artery stenosis have been extensively discussed in recent reviews and consensus. The aim of the current article is to provide comprehensive and up-to-date information on the remaining causes. While these causes are rare or extremely rare, etiologic and differential diagnosis matters both for prognosis and management. Therefore, the clinician cannot ignore them. For didactic reasons, we have grouped these different entities into stenotic lesions (neurofibromatosis type 1 and other rare syndromes, dissection, arteritis, and segmental arterial mediolysis) often associated with aortic coarctation and other arterial abnormalities, and nonstenotic lesions, where hypertension is secondary to compression of adjacent arteries and changes in arterial pulsatility (aneurysm) or to the formation of a shunt, leading to kidney ischemia (arteriovenous fistula). Finally, thrombotic disorders of the renal artery may also be responsible for renovascular hypertension. Although thrombotic/embolic lesions do not represent primary vessel wall disease, they are characterized by frequent macrovascular involvement. In this review, we illustrate the most characteristic aspects of these different entities responsible for renovascular hypertension and discuss their prevalence, pathophysiology, clinical presentation, management, and prognosis.

Open and endovascular treatment by covered and multilayer stents in the therapy of renal artery aneurysms: mid and long term outcomes in a single center experience

AIM

The purpose of this paper is to evaluate the mid and long terms outcomes of open and endovascular surgical treatment, as well as multilayer stent, in patients affected by Renal Artery Aneurysm (RAA).

PATIENTS AND METHODS

Twenty five patients with RAA (24 monolateral and 1 bilateral aneurysm, 26 aneurysms) were observed between 2000 and 2015: 4 were not treated due to the small size of the aneurysm (< 2.5 cm); out of the remaining, 16 underwent endovascular treatment, 2 were treated by open surgery consisting in aneurysmectomy and graft reconstruction and 5 (in 1 patient bilateral) were treated by ex vivo repair and autotransplantation.

RESULTS

Out of the 22 patients treated for RAA, one patient operated upon open surgery presented an early thrombosis of a PTFE graft, followed by nephrectomy (4.7%); one patient underwent autotransplantation showed an ureteral kinking without functional consequences. In a follow-up ranging from 1 and 11 years (mean 5 years), no deaths were observed; all the renal arteries repaired were patents and 16 out of 21 patients had a significative reduction of systemic blood pressure.

DISCUSSION

The choice of the best treatment is based on aneurysm's morphology according to Rundback's classification. The type I, involving the main renal artery, is always treated by endovascular approach; type II, involving renal artery bifurcations may be treated by open surgery or multilayer stents; type III (hilar or intraparenchymal aneurysms) needs only an open surgical treatment as autotransplantation.

CONCLUSION

Based on our experience it seems that most of RAAs may be treated by endovascular technique. The ex vivo autotransplantation represents the first-line treatment in hilar and intraparenchymal aneurysms. Multilayer stents seem to have good outcome in the treatment of aneurysms involving arterial bifurcations. Mid and long term results, related to kidney preservation and to normalization of blood pressure, seems satisfying.

Covered stenting and transcatheter embolization of splenic artery aneurysms in diabetic patients: A review of endovascular treatment of visceral artery aneurysms in the current era

Diabetes mellitus is associated with both microvascular and macrovascular complications, which can result in visceral aneurysms as for example splenic artery aneurysms: in their management, an endovascular treatment, less invasive than surgery, is generally preferred. Endovascular treatment of splenic artery aneurysms can be based either on covered stenting (CS) or transcatheter embolization (TE). CS generally allows aneurysm exclusion with vessel preservation, while TE usually determines target artery occlusion with potential risk of distal ischemia. We performed a review of the existing literature on endovascular treatment of visceral artery aneurysms (VAAs) and psudoaneurysms (VAPAs) in the current era.

Embolization of Renal Artery Aneurysm and Arteriovenous Fistula

A renal artery aneurysm with an associated arteriovenous fistula in a native kidney has been reported infrequently in the literature. Management depends on size, location, and the patient's physiological condition. We describe a case in which endovascular therapy was used to successfully exclude both aneurysm and fistula. This report describes a 13-centimeter renal artery aneurysm with arteriovenous fistula originating from an isolated branch of the renal artery. Coil-embolization resulted in thrombosis of the aneurysm and fistula while preserving parenchymal perfusion. Coil embolization is an alternative to surgery for coexistent renal artery aneurysm and arteriovenous fistula arising from a branch of adequate length for placement of embolic coils. Successful treatment is not limited by aneurysm size or presence of arteriovenous connection.

Management and outcomes of isolated renal artery aneurysms in the endovascular era

OBJECTIVE

Isolated renal artery aneurysms are rare, and controversy remains about indications for surgical repair. Little is known about the impact of endovascular therapy on selection of patients and outcomes of renal artery aneurysms.

METHODS

We identified all patients undergoing open or endovascular repair of isolated renal artery aneurysms in the Nationwide Inpatient Sample from 1988 to 2011 for epidemiologic analysis. Elective cases were selected from the period 2000 to 2011 to create comparable cohorts for outcome comparison. We identified all patients with a primary diagnosis of renal artery aneurysms undergoing open surgery (reconstruction or nephrectomy) or endovascular repair (coil or stent). Patients with concomitant aortic aneurysms or dissections were excluded. We evaluated patient characteristics, management, and in-hospital outcomes for open and endovascular repair, and we examined changes in management and outcomes over time.

RESULTS

We identified 6234 renal artery aneurysm repairs between 1988 and 2011. Total repairs increased after the introduction of endovascular repair (8.4 in 1988 to 13.8 in 2011 per 10 million U.S. population; P = .03). Endovascular repair increased from 0 in 1988 to 6.4 in 2011 per 10 million U.S. population (P < .0001). However, there was no concomitant decrease in open surgery (5.5 in 1988 to 7.4 in 2011 per 10 million U.S. population; P = .28). From 2000 to 2011, there were 1627 open and 1082 endovascular elective repairs. Patients undergoing endovascular repair were more likely to have a history of coronary artery disease (18% vs 11%; P < .001), prior myocardial infarction (5.2% vs 1.8%; P < .001), and renal failure (7.7% vs 3.3%; P < .001). In-hospital mortality was 1.8% for endovascular repair, 0.9% for open reconstruction (P = .037), and 5.4% for nephrectomy (P < .001 compared with all revascularization). Complication rates were 12.4% for open repair vs 10.5% for endovascular repair (P = .134), including more cardiac (2.2% vs 0.6%; P = .001) and peripheral vascular complications (0.6% vs 0.0%; P = .014) with open repair. Open repair had a longer length of stay (6.0 vs 4.6 days; P < .001). After adjustment for other predictors of mortality, including age (odds ratio [OR], 1.05 per decade; 95% confidence interval [CI], 1.0-1.1; P = .001), heart failure (OR, 7.0; 95% CI, 3.1-16.0; P < .001), and dysrhythmia (OR, 5.9; 95% CI, 2.0-16.8; P = .005), endovascular repair was still not protective (OR, 1.6; 95% CI, 0.8-3.2; P = .145).

CONCLUSIONS

More renal artery aneurysms are being treated with the advent of endovascular techniques, without a reduction in operative mortality or a reduction in open surgery. Indications for repair of renal artery aneurysms should be re-evaluated.

Renal artery aneurysm in pregnancy presenting as an arteriovenous fistula: an uncommon presentation

Renal artery aneurysms (RAAs) are uncommon. RAA is generally an incidental finding; however, in certain instances, it may be a devastating pathology. This is particularly true in case of pregnant females where the incidence of rupture is high if untreated, with high mortality rates for both the mother and the fetus. Early intervention in this particular high-risk group is advocated.

The contemporary management of renal artery aneurysms

BACKGROUND

Renal artery aneurysms (RAAs) are rare, with little known about their natural history and growth rate or their optimal management. The specific objectives of this study were to (1) define the clinical features of RAAs, including the precise growth rate and risk of rupture, (2) examine the current management and outcomes of RAA treatment using existing guidelines, and (3) examine the appropriateness of current criteria for repair of asymptomatic RAAs.

METHODS

A standardized, multi-institutional approach was used to evaluate patients with RAAs at institutions from all regions of the United States. Patient demographics, aneurysm characteristics, aneurysm imaging, conservative and operative management, postoperative complications, and follow-up data were collected.

RESULTS

A total of 865 RAAs in 760 patients were identified at 16 institutions. Of these, 75% were asymptomatic; symptomatic patients had difficult-to-control hypertension (10%), flank pain (6%), hematuria (4%), and abdominal pain (2%). The RAAs had a mean maximum diameter of 1.5 ± 0.1 cm. Most were unilateral (96%), on the right side (61%), saccular (87%), and calcified (56%). Elective repair was performed in 213 patients with 241 RAAs, usually for symptoms or size >2 cm; the remaining 547 patients with 624 RAAs were observed. Major operative complications occurred in 10%, including multisystem organ failure, myocardial infarction, and renal failure requiring dialysis. RAA repair for difficult-to-control hypertension cured 32% of patients and improved it in 26%. Three patients had ruptured RAA; all were transferred from other hospitals and underwent emergency repair, with no deaths. Conservatively treated patients were monitored for a mean of 49 months, with no acute complications. Aneurysm growth rate was 0.086 cm/y, with no difference between calcified and noncalcified aneurysms.

CONCLUSIONS

This large, contemporary, multi-institutional study demonstrated that asymptomatic RAAs rarely rupture (even when >2 cm), growth rate is 0.086 ± 0.08 cm/y, and calcification does not protect against enlargement. RAA open repair is associated with significant minor morbidity, but rarely a major morbidity or mortality. Aneurysm repair cured or improved hypertension in >50% of patients whose RAA was identified during the workup for difficult-to-control hypertension.

Hybrid Treatment of Coexisting Renal Artery Aneurysm and Abdominal Aortic Aneurysm in a Gallbladder Cancer Patient

Renal artery aneurysm (RAA) is uncommon, and the coexistence of an abdominal aortic aneurysm (AAA) is an extremely rare condition with potentially high life-threatening mortality in case of rupture. Aneurysms can be treated by endovascular intervention or open surgery. Although most of aneurysms are treated by endovascular intervention, open surgery is often necessary for RAAs associated with the proximal renal bifurcation or the branches in the distal renal arteries. We report a rare case of coexisting RAA with AAA treated by hybrid method, consisting of endovascular aneurysm repair for AAA and open surgery for RAA located adjacent to the distal branches of the renal artery.

Surgical treatment of an aneurysm of a distal branch of the renal artery

Aneurysms of the renal artery and its branches are rare, but are associated with significant morbimortality due to the absence of clinical symptoms and hemorrhagic risk in the event of rupture. We report the case of a patient with an aneurysm of a distal branch of the right renal artery that measured 25 mm in diameter. The diagnosis and localization were obtained using selective arteriography. Treatment consisted of resection of the aneurysmal sac associated with closure with a saphenous vein patch rather than an endovascular treatment in order to preserve the nephronic capital. Right renal parenchymatous vascularization was satisfactory on arterial echo-Doppler and angioscanner assessment at 1 year.

An Unusual Case of Fibromuscular Dysplasia with Bilateral Renal Macroaneurysms: Three-year Outcome After Endovascular Treatment

Fibromuscular dysplasia (FMD) is an idiopathic, segmental, non-inflammatory and non-atherosclerotic disease that affects arterial walls, leading to stenosis of small and medium-sized arteries. FMD mostly involves renal and intracranial arteries and only in few patients is associated with macroaneurysms (RAAs). We present the case of a 45-years old woman with recent history of grade 2 hypertension that suffered of subarachnoid haemorrhage due to rupture of a basilar artery aneurysm. The cerebral aneurysm was immediately treated by coil embolization and an abdominal angio-CT scan was performed to investigate the presence of renovascular hypertension. The exam showed the presence of FMD of the renal arteries associated with presence of bilateral RAAs. Due to the high risk of rupture, the bigger aneurysm (2,5 cm diameter) present on the left artery was immediately treated by coil embolization. The fusiform aneurysm, present on the right renal artery, was instead treated one year later by using two flow diverter stents. After three years, an angiographic study showed that both cerebral and renal aneurysms were excluded from the blood flow without evidence of arterial restenosis.

Bilateral ex vivo repair and kidney autotransplantation for complex renal artery aneurysms: a case report and literature review

We report the surgical management of a bilateral renal artery aneurysm diagnosed in a 41-year-old patient with a history of recurrent abdominal pain. The preoperative contrast-enhanced computed tomography showed a complex saccular aneurysm on both renal arteries within the renal hilum. The characteristics of aneurysms precluded endovascular procedures, and a double-step bilateral ex vivo reconstruction with kidney autotransplantation was planned. The intra- and postoperative period was uneventful. Imaging and laboratory examinations show preservation of renal function, and patient is symptom-free at 10-month follow up.

Renal autotransplant in patients with complex hilar renal artery aneurysms

Renal artery aneurysms are uncommon, with an incidence of 0.01% in the general population. The improvement of radiologic techniques and the increased incidence of abdominal imaging for various indications has resulted in increased detection of asymptomatic renal artery aneurysms. Hilar renal artery aneurysms are a subtype of the disease and constitute management challenges. Here, we report 3 patients with hilar renal artery aneurysms treated with renal autotransplant and review the literature.

Endovascular treatment of eight renal artery aneurysms

BACKGROUND

Renal artery aneurysms (RAA) are a relatively rare vascular entity. Treatment could be either surgical or via an endovascular route. The main aim of therapy is to prevent lethal rupture.

PURPOSE

To evaluate the angiographic and clinical results after endovascular treatment (EVT) of eight renal artery aneurysms.

MATERIAL AND METHODS

From January 2000 to June 2011, 18 patients presented with 18 renal artery aneurysms. One was classified as Rundback type I, 15 were type II, and two aneurysms were type III. Endovascular treatment was considered unsafe in 10 cases (all were Rundback type II), and were referred to surgery. The remaining eight aneurysms were treated endovascularly during altogether nine sessions. Among these, four patients were asymptomatic, three were hypertensive, and one presented with ipsilateral flank pains. Aneurysmal sac diameter varied between 12 and 50 mm. EVT included selective coil embolization in five cases, covered stents in two cases, and parent artery occlusion in one.

RESULTS

Follow-up with CT angiography was obtained in all endovascularly treated aneurysms (range 6-54 months, mean 15 months). Complete durable occlusion was achieved in all aneurysms except one, which showed re-expansion after 20 months and was retreated with covered stent implantation. Clinically silent, branch occlusion occurred after four procedures with subsequent limited (less than 25%) ischemic parenchymal loss. All patients were discharged with preserved renal function. Clinical improvement was noted in all symptomatic patients.

CONCLUSION

Endovascular treatment of renal artery aneurysms is an adequate treatment and can be proposed, if feasible, as first step.

Surgical procedures for renal artery aneurysms

OBJECTIVE

The aim of this study was to assess the strategy and surgical procedures for treating a renal artery aneurysm (RAA).

PATIENTS AND METHODS

We retrospectively reviewed the surgical strategy for 21 cases with RAA between 2001 and 2010 at this institution. Treatment was indicated for patients with an RAA larger than 2 cm and/or symptoms. Surgical treatment was the initial strategy, and coil embolization was indicated in the case of narrow-necked, saccular, extraparenchymal aneurysms.

RESULTS

Fifteen patients in 21 cases received an aneurysmectomy and renal artery reconstruction with an in-situ repair. One patient underwent an unplanned nephrectomy, and coil embolization was performed in 5 patients.

CONCLUSION

In-situ repair was safe and minimally invasive. RAA, even in the second bifurcation, could be exposed by a subcostal incision, and the transperitoneal approach permitted the safe treatment of an RAA with acceptable results, in our simple preservation of renal function.

Renal vascular lesions: diagnosis and endovascular management

Renal vascular abnormalities included in this review are renal artery aneurysms (RAA) and renal arteriovenous malformations (AVM). The clinical presentation, diagnosis, and principles of management with emphasis on endovascular techniques are discussed.

Thrombosed Aneurysm of a Segmental Renal Artery Branch. Diagnostic and Therapeutic Approach

Introduction

We present the case of a 37-year-old man with a thrombosed aneurysm of a segmental branch of the left renal artery, which was diagnosed after a radiological investigation for colic-like pain, and treated conservatively with endovascular approach.

Materials and Methods

After repeated episodes of colic-like pain in his left side with normal ultrasound of the urinary tract, A.R. (37 years old) undergoes a CT urogram of the abdomen, which shows a complete thrombosis of the middle third of the left renal artery, which is associated with hypoperfusion of the lower middle third of the kidney with suspected ischemia of the lower pole. In confirmation of the previous clinical scenario, we proceed with a urgent angiography, which identifies a pseudoaneurysm, partially thrombosed, of the segmental branch of the left renal artery at the lower middle pole. During the hospitalization, the clinical picture is complicated by an unstable arterial hypertension associated with headache and nausea. A renal scintigraphy confirms a severe impairment of the renal function mainly at the level of the middle third of the lower left kidney. The total glomerular filtration rate sec. Gates was equal to 64.3 mL/min with a percentage breakdown of the global renal function of 28% to the right and 72% to the left. The location of the vascular defect argues for endovascular intervention in the attempt to preserve the remaining renal parenchyma. We proceed with a standard angiography with selective access to the left renal artery with a catheter via femoral artery Cobra 5Fx80 TERUSMO cm. The tortuosity of the thrombus and the angle of the aneurysm site prevent, despite several attempts, the passage of the guide wire for a possible stenting and fibrinolysis. We opt for the placement of 5 spirals at the aneurysm (Boston Soft GDC-10 SR 360 7mm x 15cm), in order to preserve the residual parenchyma, excluding the aneurysmal artery at risk of rupture and extent of the thrombus.

Results

Immediately after the procedure, the clinical picture remained stable with complete remission of painful symptoms and with a good blood pressure control. At about 6 months, the renal scintigraphy shows a filtered global impairment of 70%, 30% for the left kidney, a slight improvement over the previous controls. The blood pressure remains within the limits with amlodipine 5 mg.

Conclusions

Renal artery aneurysms are uncommon and occur in approximately 0.09% of the general population. The etiopathogenesis at a young age is often dysplastic in nature and the diagnosis is made incidentally or during evaluation of related symptoms, being asymptomatic until they become complicated. Their treatment is proposed to prevent complications such as rupture or thrombosis. Given the extreme variability of presentation, the surgical technique, traditional or endoscopic, is at the surgeon's discretion. In our case, we opted for a conservative approach since the degree of renal parenchyma impairment and the patient's hemodynamic condition allowed to.

Multimodal approach to the endovascular treatment of embolisation or exclusion of the renal arteries and their distal and/or polar branches: personal experience

PURPOSE

This study reviews our experience over the last 10 years with procedures of embolisation and/or exclusion of the renal arteries, their parenchymal branches and the polar arteries [renal artery embolisation (RAE)].

MATERIALS AND METHODS

Twenty-seven patients (19 men and eight women; age range 37-93 years; mean 74 years) underwent RAE. The indications were: symptomatic gross haematuria in nine patients (33.3%) (tumour-related in seven and iatrogenic in two), symptomatic inoperable renal tumour in five (18.5%), large subcapsular or perirenal haematoma in three (11.1%) and aneurysm of the main renal artery in two (7.4%). Eight patients (29.6%) scheduled for endovascular aneurysm repair (EVAR) of the abdominal aorta underwent prophylactic embolisation of the renal polar branch arising from the aneurysmal sac or the subrenal aortic neck to prevent the possible revascularisation of the sac. Different embolisation agents were used: coils (17 cases), embolisation particles (14 cases), glue (one case), coated stent (two cases) and mechanical occlusion devices (two cases). In 11 cases, two to three different embolisation agents were used together.

RESULTS

Technical success was achieved in 26/27 patients (96.3%); in one case, embolisation of a polar artery arising from the aneurysmal sac was not possible. One case of gross haematuria recurred 13 months after the procedure and was re-treated with success. There were no cases of major or minor complications.

CONCLUSIONS

RAE is an effective and minimally invasive procedure in the treatment of neoplastic/iatrogenic symptomatic gross haematuria and in the palliative treatment of inoperable renal tumours. One possible new indication is the prophylactic exclusion of the polar artery arising from the neck or the sac of an abdominal aortic aneurysm in patients who are candidates for EVAR. In our experience, we observed very low morbidity and a short hospital stay. This procedure requires the availability of various materials for performing embolisation and experience in their use.

An 18-cm-large renal arteriovenous fistula treated by nephrectomy

Idiopathic renal arteriovenous fistulas are extremely rare. They are believed to occur as the result of congenital renal artery aneurysm that erodes into an adjacent vein. We report a case of a 48-year-old man in whom we discovered fortuitously a painless mass of the right flank. Computed tomography revealed a huge renal artery aneurysm with giant arteriovenous fistula in the absence of any clinical stigmata. Given the size of the fistula and the partial destruction of the renal parenchyma, nephrectomy was successfully performed.

Experiência preliminar com o uso da técnica de "remodelagem de colo" para tratamento endovascular de aneurismas complexos da artéria renal

OBJETIVO: Relatar os resultados preliminares da aplicação da técnica de "remodelagem do colo" no tratamento dos aneurismas de colo largo da artéria renal. MATERIAIS E MÉTODOS: Cinco pacientes (três mulheres e dois homens, com idade média de 62 anos, intervalo de 49-72 anos) com aneurismas da artéria renal variando de 10 a 25 mm de diâmetro, de colo largo, foram tratados com técnicas de embolização assistidas por "remodelagem do colo" com balão durante o período de três anos. O microbalão era posicionado diante do colo do aneurisma e insuflado, temporariamente, durante a colocação das micromolas destacáveis no interior do aneurisma. RESULTADOS: O posicionamento do balão e a colocação das micromolas foram realizados com êxito em todos os casos. Oclusão completa do aneurisma, sem protrusão de micromolas ou obstrução do vaso parental, foi alcançada em todos os pacientes. CONCLUSÃO: Nossa experiência preliminar indica que a aplicação da técnica de "remodelagem do colo" no tratamento dos aneurismas de colo largo da artéria renal é tecnicamente viável e eficaz para o tratamento endovascular de aneurismas complexos da artéria renal, sem o sacrifício de qualquer ramo arterial.

Therapy of renal artery aneurysms in New York State: outcomes of patients undergoing open and endovascular repair

The purpose of this study was to evaluate changing trends in therapy and determinants of outcomes among patients with a renal artery aneurysm (RAA) undergoing surgical or endovascular repair in New York State (NYS). A retrospective cohort study of patients who underwent therapy for RAA in NYS from October 1, 2000, to December 31, 2006, was identified from the Statewide Planning and Research Cooperative System database. Regression models which included hospital and patient characteristics were created to identify predictors of untoward events following surgical or endovascular intervention. Over this time period 215 patients with RAA repairs were analyzed. In multivariate analysis, preoperative predictors of death included diabetes (adjusted odds ratio [OR]=57.8, 95% confidence interval [CI] 2.3-1,430.1, p=0.013), the presence of other aneurysms (adjusted OR=18.5, CI 1.5-234.4, p=0.024), and coagulopathy (adjusted OR=16.9, CI 3.4-393.1, p=0.03) but not repair type. Perioperative cardiac (adjusted OR=16.7, CI 1.4-197.1, p=0.026) and vascular device-related (adjusted OR=11.1, CI 1.003-123.0, p=0.049) complications were predictive of mortality. When patients with other aneurysms were excluded from analysis (n=153), there were no significant predictors of death. Ninety-one endovascular and 124 open surgical repairs were performed with a significant increase in the proportion of endovascular repairs performed over time (p<0.001), although since 2003 the proportion of both has been roughly equal. Diabetes (15.4% vs. 5.6%, p=0.018), chronic anemia (5.5% vs. 0.8%, p=0.04), and emergent admission (48.4% vs. 24.2%, p<0.001) were more prevalent among those with endovascular repair. Endovascular therapy was associated with a lower incidence of complications, lower median length of stay (4 vs. 7 days, p<0.001), and lower rates of discharge to skilled nursing facilities (18.9% vs. 39.2%, p=0.001). There has been an increasing number of treated RAAs in NYS since 2000, with the increase being primarily in those treated by endovascular techniques. Whether this represents a true increase in RAA incidence requiring management or an extension of indications is unknown. Outcomes after endovascular repair were better than those after conventional surgery, although whether this was due to the technique of repair itself or preprocedural selection bias cannot be determined.

Saphenous vein graft aneurysm with graft-enteric fistula after renal artery bypass

A 65-year-old female presented with upper gastrointestinal hemorrhage thirty years following an aorta-to-right renal artery bypass constructed with saphenous vein. Upper endoscopy demonstrated a duodenal ulcer, and a CAT scan demonstrated aneurysmal degeneration of her renal artery bypass with duodenal impingement. Laparotomy demonstrated erosion of the aneurysm through the posterior wall of the duodenum; extra-anatomic renovascular reconstruction and primary duodenal repair was performed. Although aneurysmal degeneration of intraabdominal saphenous vein grafts is well described and rupture likewise reported, this report represents the first description of an intraabdominal autogenous vein graft aneurysm presenting with gastrointestinal erosion and fistula.

Nonoperative management of unruptured visceral artery aneurysms: treatment by transcatheter coil embolization

PURPOSE

To describe our experiences with the treatment of visceral artery aneurysms (VAA) by transcatheter coil embolization and to propose indications for treating VAA by this method.

METHODS

We treated 22 patients with VAA by coil embolization; 9 had splenic-, 7 renal-, 4 pancreaticoduodenal arcade-, and 2 proper hepatic artery aneurysms. All nine splenic artery aneurysms patients presented with chronic hepatitis-C; four had hepatocellular carcinoma. Of the seven renal artery aneurysms patients, four were hypertensive and three had rheumatoid arthritis. Both pancreaticoduodenal arcade artery aneurysms patients manifested severe stenosis of the celiac axis. Our transcatheter coil embolization procedure includes coil embolization and coil-packing of the aneurysmal sac, preserving the native arterial circulation.

RESULTS

Transcatheter coil embolization with aneurysm packing was technically successful in 16 (72.7%) of the 22 patients and the native arterial circulation was preserved. Postprocedure angiograms confirmed complete disappearance of the VAA. In four of the nine splenic artery aneurysm patients, the native arterial circulation was not preserved. In one renal artery aneurysm patient, stenosis at the aneurysmal neck necessitated placement of a stent before transcatheter coil embolization. Magnetic resonance angiographs obtained during the follow-up period (mean 27 months) demonstrated complete thrombosis of the VAA in all 22 patients. Infarction occurred in one splenic- and two renal artery aneurysms patients; the latter developed flank pain and fever after the procedure.

CONCLUSIONS

Transcatheter coil embolization is an effective alternative treatment for patients with saccular and proximal VAA. In particular, the isolation technique using coil embolization is advantageous in splenic artery aneurysm patients.

Endovascular treatment of visceral artery aneurysms

Visceral artery aneurysms, although uncommon, can present with life-threatening hemorrhage. The increasing use of imaging studies has allowed for earlier identification and intervention of these aneurysms, thus avoiding the high morbidity and mortality associated with rupture. The treatment options for visceral artery aneurysms range from conventional open surgical repair to minimally invasive techniques using covered stents or embolization materials. Anatomic features and patient selection determine which treatment option would result in the most durable treatment and outcome. This article reviews our experience with the endovascular treatment of visceral artery aneurysms.

Large Renal Artery Aneurysm Treated with Guglielmi Detachable Coils: Procedural and 4-Year Follow-up Results

A large aneurysm of the left renal artery was found incidentally during abdominal ultrasound in a 39-year-old woman with no medical or family history of cardiovascular disease. Vascular pathology with a dysplastic appearance was confirmed by magnetic resonance angiography and the patient was offered transcatheter embolization. Since the position and size of the neck of the aneurysm could not be determined at angiography, detachable platinum coils were used for occlusion. The procedure was performed without complications. During a 4-year follow-up no alterations of renal function, recanalization of the aneurysm, or perfusion defects in the rest of the left renal circulation were noted.

Tratamento endovascular de aneurisma da artéria renal por embolização com micromolas preservando o fluxo sangüíneo renal: relato de caso

O tratamento endovascular da doença aneurismática da artéria renal tem sido, cada vez mais, aceito como uma alternativa à cirurgia convencional, especialmente em casos de aneurismas complexos intra-parenquimatosos ou que comprometam a bifurcação da artéria renal. Os autores relatam a experiência do tratamento endovascular de uma paciente com aneurisma sacular da bifurcação da artéria renal direita, associado à hipertensão renovascular de difícil controle. Foi realizada a cateterização seletiva da artéria renal, com a inserção de micromolas no saco aneurismático. O aneurisma foi completamente ocluído com preservação total do fluxo sanguíneo renal. A evolução clínica foi satisfatória com redução significativa das medicações anti-hipertensivas. A angio-tomografia de controle, após o oitavo mês do procedimento, confirmou o sucesso do tratamento.

Giant Idiopathic Renal Arteriovenous Fistula Requiring Urgent Nephrectomy

Idiopathic renal arteriovenous fistulas (AVFs) with acute hemorrhage are exceedingly rare. However, a rare entity such as a renal AVF may be overlooked and have disastrous consequences, requiring an urgent management decision between endovascular or surgical treatment. We report the case of a 61-year-old man, who presented with painless gross hematuria and clot retention. Computed tomography revealed a giant renal arteriovenous malformation, in the absence of any clinical stigmata such as hypertension or congestive heart failure. Gross hematuria resulted from AVF erosion into the collecting system. Given the size of the AVF, endovascular coil embolization was attempted but deemed too risky, necessitating urgent nephrectomy.