Congenital Renal Arteriovenous Malformations Research Articles

Congenital Renal Arteriovenous Malformation: Diagnostic Clues and Methods.

Background and objectives: Renal arteriovenous malformation (AVM) is a rare disease and is difficult to be diagnosed by conventional methods because of its rarity. In this study, we investigated the diagnostic clues, and made an algorithm for the better diagnosis of renal AVM. Materials and Methods: We reviewed 13 patients who were diagnosed with AVM by using renal angiography from 1986 to 2020 at our institutes. We evaluated clinical features, diagnostic tools, treatment modalities, and outcomes after the treatment of patients. Results: All patients were female, and the mean age was 36.9 years (range 19 to 54 years). Twelve (92.3%) patients complained of gross hematuria. Four (30.8%) patients showed symptoms in relation with pregnancy and delivery. Angiographic findings demonstrated cirsoid type in 10 patients and aneurysmal type in 3 patients. Among the 11 patients who underwent computed tomography, AVMs were detected in 3 (27.3%) patients. Renal duplex Doppler was performed in 6 patients, and all of these patients were diagnosed with AVM, demonstrating a vascular turbulence or blood-rich area. Twelve patients were initially treated with transarterial embolization. Nephrectomy was performed in two patients due to persistent bleeding with hypovolemic shock. Conclusions: We should consider possible AVMs in patients who were not detected by conventional work up for hematuria, especially in mid-aged, pregnant, or recently delivered women. Renal duplex Doppler might be the optimal diagnostic modality in these patients. Our diagnostic algorithm could be aid to diagnosis and treatment for renal AVM patients.

Renal arteriovenous malformation: An unusual pathology.

Renal arteriovenous malformations are rare renal vascular abnormalities. More commonly, the term refers to the congenital type of malformation. Only a few cases have ever been presented and reported in the literature, mostly with a nidus. We present the clinical, ultrasound and computed tomography findings and discuss the management related to a 63-year-old male with a right congenital renal arteriovenous malformation without a nidus that was successfully managed with coil embolisation. Relevant literature is hereby reviewed to highlight characteristic imaging and appropriate treatment.

Efficacy and Safety of Transvenous Embolization of Type II Renal Arteriovenous Malformations with Coils

PurposeTo evaluate the efficacy and safety of transvenous coil embolization of the venous sac for type II renal arteriovenous malformation (AVM). Materials and MethodsA retrospective review was conducted of 8 patients (5 women and 3 men; mean age, 57 years; age range, 41–69 years) who underwent transvenous coil embolization for type II congenital renal AVM at 5 different hospitals between 2012 and 2018. Additional intra-arterial ethanol injection was performed if shunt flow persisted after venous sac coiling. Technical success was defined as complete occlusion of shunt flow with coil embolization. Clinical success was defined as no symptom recurrence during the follow-up period. The renal parenchymal infarction rate was measured on computed tomography (CT), and procedure-related complications were reviewed. ResultsNine sessions of embolization were performed for 8 patients. The mean venous sac size was 24 mm (range, 10–39 mm), and a mean of 14 micro and/or micro-detachable coils (range, 3–50) were used. The technical success rate was 88% (7 of 8) using coil embolization. One patient (12%) required additional ethanol injection to complete occlusion of the shunt flow and had a less than 10% parenchymal infarction on follow-up CT. No procedure-related complications or recurrences occurred during a mean clinical follow-up period of 20.8 months (range, 4.7–76.6 months). ConclusionsTransvenous coil embolization of type II renal AVM showed an 88% technical success rate. One patient (12%) showed less than 10% renal parenchymal infarction after additional ethanol injection. No additional complications or recurrences occurred during the follow-up period.

Varicocele due to renal arteriovenous malformation mimicking a renal tumor: a case report

BackgroundRenal arteriovenous malformation is an aberrant vascular connection between the renal artery and vein. Acquired renal arteriovenous malformation (arteriovenous fistulae) accounts for approximately 70% of renal arteriovenous abnormalities. Congenital renal arteriovenous malformation, relatively rare, can result in significant hematuria which may require arterial embolization or nephrectomy.Case presentationA 64-year-old Asian man presented to the Urology department in our hospital with gradual left scrotal swelling for 2 years. Ultrasound and computed tomography showed an irregular mass in the upper pole of his left kidney. Digital subtraction angiography confirmed cirsoid-type left renal arteriovenous malformation combined with left renal vein ostial stenosis. After digital subtraction angiography and selective segmental renal artery embolization, the varicocele was obviously alleviated.ConclusionsThe etiology diagnosis of varicocele is not always straightforward, and renal arteriovenous malformation should be considered in the differential diagnosis of varicocele and renal mass. Renal arteriovenous malformation is difficult to distinguish from renal tumor according to varicocele and computed tomography presentation, while magnetic resonance imaging and digital subtraction angiography help to make a definite diagnosis and selective renal angiographic embolization is one of the best treatments for renal arteriovenous malformation.

Endovascular Treatment of 12 Cases of Renal Arteriovenous Malformations: The Experience of 1 Center and an Overview of the Literature.

Congenital renal arteriovenous malformations (rAVMs) represent rare vascular diseases. The heterogeneous vascular architecture of each rAVM determines the endovascular treatment techniques employed. We reported our experience with the endovascular treatment of a series of rAVMs. This retrospective study consisted of 12 patients with 12 rAVMs who underwent renal arterial embolization (RAE) in our hospital. Embolic materials, including particles, liquid embolic agents (n-butyl 2-cyanoacrylate, Onyx, and ethanol), and coils, were selectively used based on the decisions of interventional radiologists. Technical success was defined as the complete occlusion of the feeding arteries and nidus on postprocedure renal arteriography. Clinical success was defined as the resolution of hematuria or the disappearance of rAVM-relevant symptoms. The median follow-up period was 13.5 months (range: 4-72). The technical success based on 12 procedures in 12 patients was 83.3% (10 of 12). In the 2 procedures that technically failed, the existence of multiple fine feeding arteries arising from the proximal portion of different segmental renal arteries explains the incomplete embolization. One of the 2 patients achieved clinical success without additional RAE. The other patient had recurrent hematuria 25 months after initial treatment, which was successfully managed conservatively with hemostatic agents. Thus, the clinical success was 91.7% (11 of 12). Renal artery embolization with the selective use of various embolic materials is an effective treatment for patients with rAVMs. The existence of multiple fine feeding vessels arising from the proximal portion of different segmental renal arteries is likely to affect the technical success of treatment.

Transarterial embolisation for congenital renal arteriovenous malformations improves clinical condition even with partial obliteration

To evaluate the efficacy and safety of transarterial embolisation (TAE), used to treat congenital renal arteriovenous malformations (CRAVMs). The medical records were searched retrospectively to identify patients who underwent TAE to treat CRAVM from January 2003 to August 2015. Patient demographics, clinical presentations, and imaging findings were reviewed. TAE outcomes, including complete or partial obliteration, clinical success, complications, renal function changes, and relapse of symptoms or signs after the final TAE, were assessed. Over the 12-year period, 16 patients (nine male, seven female; median age, 47 years) who underwent 21 TAE procedures to treat 16 CRAVMs were enrolled in the study. The most common clinical presentation was haematuria (81.3%). Thirteen patients (81.3%) had cirsoid and three (18.7%) had aneurysmal CRAVMs. Of the 16 CRAVMs, 11 (68.8%) were peripheral, four (25%) were central, and one (6.3%) was both peripheral and central. The complete obliteration rate was 56.3%. The clinical success rate was 87.5% over a median follow-up period of 398.5 days. Two (9.5%) major complications and 14 (66.7%) minor complications were encountered. No statistically significant change in renal function was evident after TAE. TAE was safe and effective when used to treat CRAVM; the complication profile was acceptable and renal function was preserved. TAE improved the clinical condition of CRAVM patients even when obliteration was only partial.

Embolization of Congenital Renal Arteriovenous Malformations Using Ethanol and Coil Depending on Angiographic Types

PurposeTo evaluate effectiveness and safety of embolization of congenital renal arteriovenous malformations (AVMs) using ethanol and/or coil according to angiographic type. Materials and MethodsBetween August 2010 and October 2015, 11 patients (13 sessions; 10 women and 1 man; mean age, 50.8 y) with congenital renal AVMs were treated using ethanol and/or coils via 2 approaches (transarterial access or direct puncture). Demographics, clinical findings, diagnostic modalities, angiographic types, technical and clinical success rates, and complications were reviewed. Renal AVMs were classified into 3 angiographic types, and treatment was based on this classification. ResultsTechnical success rate was 91% (10/11), and clinical success rate was 100% (11/11). Of patients, 7 had type III AVMs, 3 had type I AVMs, and 1 had type II AVM. Embolic agents were ethanol in 5 patients, coils with ethanol in 3 patients, and coils in 3 patients. Of the 8 patients treated with ethanol, 6 had infarcted renal areas of 3.5%–30% (mean, 14.6%). After a mean follow-up period of 16.3 months, there was no evidence of recurrent AVMs on imaging or laboratory studies. ConclusionsEmbolization of congenital renal AVMs via transarterial or direct percutaneous approaches using ethanol and/or coils based on a simple angiographic classification was safe and effective and elicited good outcomes. Most of the patients with congenital renal AVMs were women.

Massive hematuria due to congenital renal arteriovenous malformation successfully treated by renal artery embolization

Massive hematuria due to congenital renal arteriovenous malformation successfully treated by renal artery embolization

Novel Endovascular Management of Bilateral Congenital Renal Arteriovenous Malformations: Case Report and Clinical Review

Novel Endovascular Management of Bilateral Congenital Renal Arteriovenous Malformations: Case Report and Clinical Review

Congenital renal arteriovenous malformation presenting with gross hematuria after a routine jog: a case report

IntroductionCongenital renal arteriovenous malformations are abnormal communications between the intrarenal venous and arterial systems. An unusual cause of massive gross hematuria and an even rarer cause of hemodynamically significant anemia, its presentation remains variable from incidental imaging findings to severe hypertension and congestive heart failure.Case presentationWe present a case of a 44-year-old Chinese man with no personal or familial history of bleeding diasthesis that presented with gross hematuria leading to clot retention after routine physical activity.ConclusionsWe have presented this case in an effort to highlight the possibility of this entity as a cause of acute upper urinary tract hemorrhage and the need for a computed tomography angiogram to clinch the diagnosis.

Large congenital renal arteriovenous malformation treated with interlock coil embolization

Renal vascular malformation is an abnormal communication between the intrarenal arterial and venous system. These malformations include arteriovenous malformation (AVM) and arteriovenous fistula (AVF).1 Renal AVM is a congenital developmental abnormality in which the renal artery and renal vein communicate through a network of abnormal vessels. By contrast, renal AVF is a direct communication between an artery and a vein. The etiology of congenital AVM is unknown, while the cause of acquired renal AVF is usually found to be percutaneous renal biopsy, other procedures, and incidental renal trauma. A 57-year-old woman visited our hospital with intermittent left flank discomfort of several years’ duration. The symptom had worsened with position change and had become particularly bothersome during the preceding few months. She had no past medical history including trauma or procedures. On physical examination, a continuous bruit was audible over the left flank area. Urinalysis and blood tests showed normal findings. A contrast-enhanced computed tomography scan of the abdomen demonstrated aneurysmally dilated enhancing vessels with attenuation similar to the arteries in the left kidney (Panel A). Digital subtraction arteriography showed a feeding artery to a large AVM with abnormal dilation of the nidus and early opacification of venous flow (Panel B1). In this patient, the large AVM was treated with interlock coils (Panel B2). After super-selective catheterization, coil-embolization of all feeders was performed successfully (Panel B3). Magnetic resonance imaging (MRI) before treatment presented aneurysmally dilated vessels with high flow and suggested an underlying vascular malformation (Panel C1). A followup MRI taken 6 months post-embolization showed successful occlusion of the AVM with coils (Panel C2). In this case, AVM was managed with deployment of coils into the vascular malformation, which promoted thrombosis.2 Complications can arise from the rapid shunting of the coils into the venous circulation, leading to emboli entering the pulmonary circulation or the left side of the heart if interarterial communication exists. Blocking the venous output of the AVM can help in preventing this complication. It is also important for the angiographer to be familiar with retrieval techniques if such a complication arises.3 Images in Vascular Medicine

The Role of Transarterial Embolization in the Management of Hematuria Secondary to Congenital Renal Arteriovenous Malformations

Objective: To evaluate the efficacy and safety of transarterial embolization (TAE) in the management of hematuria secondary to congenital renal arteriovenous malformations (AVM). Patients and Methods: Between May 2007 and February 2012, 6 patients with congenital AVM treated with TAE were analyzed retrospectively, followed by a brief review of TAE in the treatment of congenital AVM. Clinical records with respect to general conditions, location, embolic materials, complications and overall outcome were collected from the original hospital charts and outpatient medical records. Results: Three patients with AVM were confirmed by contrast-enhanced CT scans, and the other 3 patients were detected by renal angiography. TAE was performed with steel coils in 2 patients and n-butyl-2-cyanoacrylate (NBCA) in 4 patients. After a mean follow-up of 22 months, no serious adverse effects were observed in all patients. There were no complaints of hematuria at the end of the follow-up period. Conclusion: For unexplained massive hematuria, congenital renal AVM needs to be considered as a differential diagnosis. Selective renal angiography and embolization should be recommended as the first choice to treat massive hematuria secondary to congenital renal AVM.

Renal arteriovenous malformation, hypertension and heart failure: culprit or confounder?

Summary Congenital renal arteriovenous malformation (RAVM) is an extremely rare abnormality with about 200 reported cases. It may be asymptomatic and found incidentally, or present with cardiac or renal symptoms. Hence establishing the physiological and clinical significance of RAVM is crucial in identifying patients in need of treatment and selecting the appropriate treatment. Herein, we report the rare case of a patient presenting with accelerated hypertension, heart failure and a congenital RAVM. We discuss the approach to assessment and treatment of congenital RAVMs in the context of cardiac disease.

Flank bruits due to giant renal arteriovenous malformation.

A 58-year-old woman was referred to the nephrology department because of a continuous bruit over the right flank heard by her primary care physician. Blood pressure was 120/80 mmHg. Complete blood count and urinary analysis were within normal limits. She had no history of prior renal surgery or trauma. A large cyst-like lesion at the right kidney with turbulent blood flow was found on colour Doppler ultrasound. Volume-rendered computed tomography (CT) angiography (Figure 1A) demonstrated giant cirsoid aneurysmal dilations of the right renal artery with early opacification of right renal vein (arrow) and inferior vena cava (arrowhead), indicating congenital renal arteriovenous malformations (AVMs). Therefore, right renal artery angiography (Figure 1B) confirmed the diagnosis of right giant renal AVMs by demonstrating cirsoid arterial communication with early visualization of the right renal vein (arrow) and inferior vena cava (arrowhead). At the same time, endovascular embolization of right AVMs was performed successfully with preservation of renal parenchymal vascular supply. The patient’s post-operative course was uneventful, and she was well 6 months later. Fig. 1 Volume-rendered computed tomography angiography (A) showing giant cirsoid aneurysmal dilations of right renal artery with early opacification of right renal vein (arrow) and inferior vena cava (arrowhead), indicating of congenital renal arteriovenous ... Renal AVMs are an uncommon disease of abnormal communications between intrarenal arterial and venous systems. These malformations can be congenital or acquired due to trauma, surgery and tumours. Acquired AVMs are often termed renal arteriovenous fistula. Congenital AVMs are a rare disease and account for 25% of renal AVMs [1]. Most congenital AVMs are asymptomatic. Symptomatic AVMs usually present with microscopic or gross haematuria, abdominal pain and flank bruit [2]. Renal Doppler sonography is a non-invasive tool that can help in distinguishing vascular lesions from cystic lesions based on a turbulent blood flow [3]. Renal CT angiography showed a typical appearance of cirsoid arterial communication with early visualization of inferior vena cava, indicating congenital arteriovenous malformations. Renal arteriography is still the gold standard modality which can help in a clearly visualization of abnormal vessels with early draining veins and the nidus of the AVM. Transcatheter embolization of renal AVMs can successfully obliterate the nidus of AVMs and preservation of renal normal parenchyma with reduced morbidity in comparison with surgical resection of renal AVMs [4]. Conflict of interest statement. None declared.

Fístulas arteriovenosas renales como causa de hipertensión arterial refractaria

The prevalence of congenital renal arteriovenous malformations is low; for this reason, they are a very uncommon cause of arterial hypertension. However, arterial hypertension due to congenital renal arteriovenous malformations is potentially curable; thus, it is important to reach the correct diagnosis so that the natural course of the hypertension refractory to drug therapy can be modified. We present a case of a patient with bilateral congenital renal arteriovenous fistulas that were treated with two different embolization techniques in function of the morphology of the fistula and the intensity of the flow; treatment achieved control of the clinical symptoms of hypertension.

Spontaneously Ruptured Congenital Arteriovenous Malformation of Unilateral Renal Agenesis in Woman with Urinary Retention

Congenital renal arteriovenous malformations are rare. Moreover, rupture of congenital arteriovenous malformations in the unilateral renal agenesis with uterine malformation is more rare. We present a case of acute urinary retention due to large hematoma of spontaneously ruptured congenital arteriovenous malformation of unilateral renal agenesis in a 33-years-old woman. (J Korean Continence Soc 2009;13: 169-72)

Massive hematuria due to a congenital renal arteriovenous malformation mimicking a renal pelvis tumor: a case report

IntroductionCongenital renal arteriovenous malformations (AVMs) are very rare benign lesions. They are more common in women and rarely manifest in elderly people. In some cases they present with massive hematuria. Contemporary treatment consists of transcatheter selective arterial embolization which leads to resolution of the hematuria whilst preserving renal parenchyma.Case presentationA 72-year-old man, who was heavy smoker, presented with massive hematuria and flank pain. CT scan revealed a filling defect caused by a soft tissue mass in the renal pelvis, which initially led to the suspicion of a transitional cell carcinoma (TCC) of the upper tract, in view of the patient's age and smoking habits. However a subsequent retrograde study could not depict any filling defect in the renal pelvis. Selective right renal arteriography confirmed the presence of a renal AVM by demonstrating abnormal arterial communication with a vein with early visualization of the venous system. At the same time successful selective transcatheter embolization of the lesion was performed.ConclusionThis case highlights the importance of careful diagnostic work-up in the evaluation of upper tract hematuria. In the case presented, a congenital renal AVM proved to be the cause of massive upper tract hematuria and flank pain in spite of the initial evidence indicating the likely diagnosis of a renal pelvis tumor.

Heart Failure and Severe Pulmonary Hypertension Secondary to a Giant Renal Arteriovenous Malformation

Renal arteriovenous malformations (AVMs) are anomalous communications between the arterial and venous systems of the kidneys, with no intermediate capillary vessels. 1,2 The malformations may be either congenital or acquired, the latter being much more common. In 75% of cases, the initial sign of a renal AVM is gross hematuria, 1-3 and large malformations may cause heart failure. 1,2,4 We report a case of severe pulmonary hypertension and heart failure with no hematuria secondary to a giant congenital renal AVM in a 61-year-old woman. The disorder was diagnosed first with duplex color Doppler sonography and later confirmed by computed tomography (CT), magnetic resonance angiography, and angiography A laparoscopic nephrectomy was performed successfully.

Unusual Clinical Manifestations of Congenital Renal Arteriovenous Malformation

Congenital renal arteriovenous malformation (ATM) is a rare clinical disease. Due to the recent availability of color-Doppler ultrasound and angiography, the successful detection rate of congenital renal ATM has increased. The treatments of choice range from transcatheter arterial embolization (TAE) to nephrectomy. However, the goal of treatment is to preserve a high degree of renal function. In this paper, we report on a case of congenital renal ATM presented with gross hematuria and right flank pain. Abdominal computed tomography revealed a huge cystic tumor mass over the right retroperitoneal space. Renal cell carcinoma was highly suspected. Following color-Doppler ultrasound and angiography, a right renal aneurysm was detected. Sever impairment of renal function and renal atrophy were noted as well. Finally, the patient received total nephrectomy. However, the histopathological analysis of the tumor found it to be a ruptured renal AVM. Neither hematuria nor flank pain were found during follow-up.

Congenital Renal Arteriovenous Malformation - 3 Cases Report

In the last 2 decades, diagnosis of congenital renal arteriovenous malformation has increased owing to the availability of angiography. Recently, color Doppler ultrasound has played an adjunctive role in the detection of renal A VM for its non-invasive means and efficiency. Meanwhile, the treatment of choice has changed from nephrectomy to transarterial embolization for minimizing renal parenchymal damage. In this report, congenital renal AVM leading to gross hematuria was diagnosed in 3 females. Three lesions were all detected by color Doppler ultrasound and were proved by renal angiography. Superselective transarterial embolization was performed in these 3 cases. For 1.5-yr follow-up, no more microscopic or gross hematuria was found.