Renal artery aneurysms

An isolated right renal hilum false aneurysm: A rare complication of Behçet's disease

Behçet's disease is a systemic vasculitis of unknown origin. It mainly affects young men. Vascular involvement mainly affects the veins and may manifest as deep or superficial thrombosis. Arterial involvement is rare and serious. Arterial thrombosis or aneurysms/false aneurysms can be life threatening in case of rupture. All the arteries in the body can be affected, with widely varying frequencies. Involvement of the renal arteries is very rare. We report the case of a young patient followed for schizophrenia and known to have Behçet's disease, in whom a false aneurysm of the right renal artery was diagnosed during hematuria. He unfortunately refused any type of intervention.

Comparative Efficacy and Safety of Self-Expandable vs. Balloon-Expandable Stent Grafts in Visceral Artery Aneurysm Management

PURPOSE

This study assesses the efficacy and safety of self-expandable (SE) versus balloon-expandable (BE) stent grafts for managing visceral artery aneurysms (VAAs), focusing on procedural success and complication rates.

MATERIALS AND METHODS

We conducted a retrospective analysis of VAA patients treated at our institution from April 2006 to September 2021. The study reviewed patient demographics, aneurysm characteristics, treatment details, and outcomes, including endoleaks.

RESULTS

Among the 23 patients analyzed, splenic artery aneurysms represented 44% of cases. Fifteen patients were treated with balloon-expandable stent grafts (BE SGs), and eight patients were treated with self-expandable stent grafts (SE SGs). For saccular aneurysms, the average neck size was 10.10 ± 8.70 mm in the BE group versus 18.50 ± 3.40 mm in the SE group (p = 0.23), with an average sac size of 20.10 ± 18.9 mm in the BE group versus 15.60 ± 12.7 mm in the SE group (p = 0.16). The average sac-to-neck ratio was 1.69 ± 2.23 in the BE group versus 1.38 ± 0.33 in the SE group (p = 0.63). The BE group exhibited a significantly higher endoleak rate (60%) compared to the SE group (12.5%; p = 0.03).

CONCLUSIONS

While further investigation is needed to fully assess the outcomes of stent graft treatment for VAAs, initial data show a significantly higher endoleak rate with BE SGs compared to SE SGs. The SE SGs may offer better outcomes due to their superior ability to conform to tortuous and mobile visceral arteries.

A Qualitative Systematic Review of Endovascular Management of Renal Artery Aneurysms

PURPOSE

To perform a qualitative systematic review of endovascular management of renal artery aneurysms (RAAs).

MATERIALS AND METHODS

A comprehensive electronic search of PubMed, MEDLINE, Embase, Google Scholar, and Cochrane databases from 2000 to 2022 was performed using the search terms "renal artery," "aneurysm," and "endovascular." Means of outcome measures were calculated with a primary end point focused on RAA-related mortality and rupture. Secondary end points included reintervention rate and renal infarction.

RESULTS

Twenty-six, single-center, retrospective, observational studies were included. There were 454 RAAs treated in 427 patients using endovascular techniques. Mean age was 53.8 years, with a female predominance (62%). A variety of endovascular treatments of RAA were used with excellent technical success (96%), renal parenchymal preservation, and a low rate of moderate/severe adverse events (AEs). Primary coil embolization was the most commonly used technique (44.7%). There was an overall AE rate of 22.9%, of which 6.7% were moderate/severe and there was 0% periprocedural mortality. The most common AE was renal infarction (49 patients, 11.5%); however, renal function was preserved in 84% of patients. Nephrectomy rate was 0.4%. Computed tomography (CT) angiography was the most common imaging follow-up modality used in 72% of studies. Only 9 studies (34%) reported anticoagulant use. Although the risk of delayed aneurysm reperfusion warrants clinical and imaging surveillance, relatively few patients (3%) required reintervention in this cohort.

CONCLUSIONS

Endovascular management of RAA is a technically feasible treatment option with low rates of AEs and reintervention. The present study highlights the techniques available for interventional radiologists, a need for standardization of AE reporting, anticoagulation therapy, and follow-up imaging.

Management of renal artery aneurysms: A retrospective study

BACKGROUND

Although renal artery aneurysms (RAAs) are rare and often asymptomatic with slow growth, their natural progression and optimal management are not well understood. Treatment recommendations for RAAs do exist; however, they are supported by limited data.

METHODS

A retrospective cohort study was conducted to explore the management of patients diagnosed with an RAA at our institution from January 1st, 2013, to December 31st, 2020. Patients were identified through a search of our radiological database, followed by a comprehensive chart review for further assessment. Data collection encompassed patient and aneurysm characteristics, the rationale for initial imaging, treatment, surveillance, and all-cause mortality.

RESULTS

One hundred eighty-five patients were diagnosed with or treated for RAAs at our center during this timeframe, with most aneurysms having been discovered incidentally. Average aneurysm size was 1.40 cm (±0.05). Of those treated, the mean size was 2.38 cm (±0.24). Among aneurysms larger than 3 cm in size, comprising 3.24% of the total cases, 83.3% underwent treatment procedures. Only 20% of women of childbearing age received treatment for their aneurysms. There was one instance of aneurysm rupture, with no associated mortality or significant morbidity.

CONCLUSIONS

Our institution's management of RAAs over the period of the study generally aligned with guidelines. One potential area of improvement is more proactive intervention for women of childbearing age.

Intraoperative Blood Flow Evaluation Using Indocyanine Green Fluorescence Angiography for the Surgical Reconstruction of a Hilar Renal Artery Aneurysm

Surgical reconstruction is one of the standard treatments for renal artery aneurysm. However, its intraoperative evaluation is sometimes difficult depending on the operative field, aneurysm morphology, and peripheral blood vessel distribution. This case demonstrated that after renal artery reconstruction, indocyanine green fluorescence angiography is used to evaluate the results of repairing. This method is useful in visceral aneurysm evaluation not only for assessing reconstructed blood flow but also for confirming tissue perfusion of the renal parenchyma.

Safety of Patients with Renal Artery Aneurysm to Proceed with Living Donation

BACKGROUND

Renal artery aneurysm (RAA) is a rare condition that involves dilation of all layers of the arterial wall of the renal artery. The risk of rupture is rare, but intervention is recommended for larger aneurysms. Surgical decision-making regarding live donor renal transplantation (LDRT) centers around safety for the living donor, and laterality of the donated kidney is based on providing the donor with the best longevity pertaining to the remaining kidney. We looked to review our long-term outcomes surrounding live donor transplants from donors with RAA with ex vivo resection and reconstruction prior to implantation.

METHODS

A retrospective review was done of all laparoscopic live donor transplant nephrectomies with ex vivo aneurysm resection, reconstruction, and implantation at a single center.

RESULTS

Three pairs of patients underwent successful laparoscopic donor nephrectomy, RAA resection, reconstruction, and transplantation of kidney. 2 males and 1 female ages 47 to 58 years of age underwent transplantation. The donors at 5 years of follow-up were noted to be functioning appropriately with no long-term sequelae of their donation and a mean remanent kidney function of 63 mL/min.

DISCUSSION

For potential live donors with asymptomatic, unilateral renal artery aneurysm and no systemic disease, live donation with ex vivo resection and reconstruction can be performed with excellent long-term donor and recipient outcomes.

Contained rupture of a left renal artery aneurysm: Report of a case

Ruptured renal artery aneurysms are uncommon. Although the increased use of endovascular technologies, controversy persists over the management. Contained rupture may be more difficult to diagnose, hence delay the management. We report a case of contained rupture of renal artery aneurysm treated with selective embolization prior to nephrectomy.

An Anatomic Classification Scheme for Surgical Planning of Renal Artery Aneurysms

PURPOSE

Renal artery aneurysm (RAA) is a rare disease. This study proposed and evaluated a new classification for RAA to assist in surgical decision-making.

MATERIALS AND METHODS

Single-center data of 105 patients with RAAs from the vascular department of vascular surgery were collected retrospectively. A new classification scheme was proposed. Type I aneurysms arise from the main trunk, accessory branch, or first-order branches away from any bifurcation. Type II aneurysms arise from the first bifurcation with narrow necks (defined as dome-to-neck ratio >2) or from intralobular branches. Type III aneurysms with a wide neck arise from the first bifurcation and affect 2 or more branches that cannot be sacrificed without significant infarction of the kidney.

RESULTS

There was 50 (47.62%) type I, 33 (31.43%) type II, and 22 (20.95%) type III aneurysms. The classification assigned endovascular repair as first-line treatment (for type I or II), while open techniques were conducted if anatomically suitable (for type III). A kappa level of 0.752 was achieved by the classification compared with a level of 0.579 from the classic Rundback classification. Technical primary success was achieved in 100% and 96.05%, and symptoms were completely resolved in 100% and 84.85%, while hypertension was relieved in 84.21% and 72.92% of patients receiving open surgery or endovascular repair, respectively. No significant difference was observed for perioperative or long-term complications among the 3 classification types.

CONCLUSION

The new classification proved to be a convenient and effective method for facilitating choice of intervention for RAAs.

CLINICAL IMPACT

This study proposed and evaluated a new classification scheme for renal artery aneurysms, which proved to be a convenient and effective method for facilitating surgical decision-making. Coil embolization was the first-line treatment if suitable, while aneurysm resection and reconstruction with vein graft were conducted for some complex lesions. The safety and efficacy of both open and endovascular methods were validated.

Surveillance of a Transplant Kidney Harboring a Stable Renal Artery Aneurysm: A Case Report

Renal artery aneurysms (RAAs) may occur in patients with transplanted kidneys, either through de novo development or as a preexisting feature of the donor kidney. How this vascular condition progresses in patients on immunosuppressive therapy after transplantation is poorly understood, and to our knowledge, consensus guidelines for treating transplant patients with RAA have not been developed. We present the case of a kidney allograft recipient on triple immunosuppressive therapy in whom postoperative imaging revealed a 13-mm renal artery aneurysm in the renal hilum not amenable to endovascular intervention. We review systemic influences on aneurysm formation and how matrix metalloproteinases may interact with immunosuppressive medications. Surveillance imaging over 5 years has shown a stable aneurysm, and the patient has maintained stable renal function with adequate creatinine levels and no adverse symptoms.

In situ open repair of renal artery aneurysm in 43-year-old with solitary kidney: a case report

Renal artery aneurysms are rare. Indications for management include size > 3 cm, female gender within childbearing age, pain, hematuria, medically refractory hypertension, thromboembolism, dissection, and rupture. Management options include endovascular, open repair, and ex vivo approaches. A 43-year-old female with a history of polycystic kidney disease, solitary kidney, and uncontrolled hypertension was found to have a proximal large renal aneurysm on imaging. The patient underwent an in situ open aneurysm resection, temporary shunt insertion, and patch repair with good postoperative outcomes. Whereas previous studies showed the success of ex vivo repair and autotransplantation in large aneurysms with solitary kidneys, our case demonstrated that in situ open repair and patch with the use of a temporary shunt is a feasible and effective option. In a patient with a solitary kidney and large proximal renal artery aneurysm, an in situ open approach and patch repair with shunt insertion should be considered.

Outcomes of endovascular, open surgical and autotransplantation techniques for renal artery aneurysm repair: a systematic review and meta-analysis

BACKGROUND

Renal artery aneurysms (RAA) can be repaired with endovascular exclusion (EVR), open repair (OR), or ex-vivo repair with renal autotransplantation (ERAT). This systematic review compares repair indications, aneurysm characteristics, and complications following these interventions.

METHODS

A systematic review of databases including MEDLINE, PUBMED, and EMBASE by two independent reviewers for studies from January 2000-November 2022. All studies evaluating repair indications, RAA morphology, morbidity and mortality following EVR, OR, and ERAT were included.

RESULTS

A total of 38 studies were included with 1540 EVR, 2377 OR and 109 ERAT subjects. Increasing aneurysm size, or diameters >20 mm, were the most common repair indications across EVR and OR (n = 537; 48%), and ERAT (n = 23; 52%). All ERAT repairs were at or distal to renal artery bifurcations (n = 46). Meta-analyses demonstrated significantly shorter length of stay (LOS) with EVR compared to OR (mean difference -4.06, 95% confidence interval (CI) -5.69 to -2.43, P < 0.001). No significant differences were found in mean aneurysm diameter (P = 0.23), total complications (P = 0.17), and mortality (P = 0.85). Major complications (Clavien-Dindo ≥III) across studies most commonly included acute renal failure (EVR 4.9% vs. OR 7.0%). Nephrectomy was the most common major complication in ERAT (5.5%).

CONCLUSIONS

Outcomes following EVR and OR of RAAs are comparable. EVR offers a shorter LOS, with no difference in morbidity or mortality. ERAT is currently only utilized for distal RAAs, however carries higher risk of infarction and nephrectomy necessitating specialized expertise or algorithms to assist appropriate selection of repair methods.

CEUS Bosniak Classification-Time for Differentiation and Change in Renal Cyst Surveillance

It is time for a change. CEUS is an established method that should be much more actively included in renal cyst monitoring strategies. This review compares the accuracies, strengths, and weaknesses of CEUS, CECT, and MRI in the classification of renal cysts. In order to avoid overstaging by CEUS, a further differentiation of classes IIF, III, and IV is required. A further development in the refinement of the CEUS-Bosniak classification aims to integrate CEUS more closely into the monitoring of renal cysts and to develop new and complex monitoring algorithms.

Diagnostic and therapeutic strategies for vascular complications after renal transplantation: a single-center experience in 2,304 renal transplantations

Vascular complications after renal transplantation are one of the serious surgical complications, which can affect the transplantation outcome and even endanger life if not treated properly. We performed a retrospective analysis of the 2,304 renal transplantations procedures completed between the period of Jan., 2015 and Jan., 2022, which consisted of 1,658 male patients and 646 female patients. Among the above cases, there were 54 cases of vascular complications after renal transplantation, the incidence of vascular complications in our study was 2.34% (54/2,304), the most common vascular complication was transplanted renal artery stenosis (TRAS, n = 36), followed by external iliac artery dissection (n = 5), renal artery rupture (n = 4), renal vein thrombosis (n = 3), renal artery thrombosis (n = 2), renal artery dissection (n = 1), renal artery pseudoaneurysm (n = 1), and internal iliac artery pseudoaneurysm (n = 1), and renal artery kinking (n = 1). 40 patients were treated by percutaneous transluminal angioplasty (PTA), including 3 balloon catheter dilatation and 37 endovascular stentings, and 14 underwent open surgery. Eventually, 9 patients had graft nephrectomy, resulting in an overall treatment rate of 81.5%. Most vascular complications can be treated satisfactorily with PTA. However, the overall treatment of renal artery rupture, thrombosis, renal artery kinking, and other complications is poor, and the rate of transplanted renal loss is high.

Natural history of renal artery aneurysms

OBJECTIVE

The existing renal artery aneurysm (RAA) literature is largely composed of reports of patients who underwent intervention. The objective of this study was to review the natural history of RAA.

METHODS

This single-institution retrospective analysis studied all patients with RAA diagnosed by computed tomography imaging between 2015 and 2019, identified by our institutional radiology database. Imaging, demographic, and clinical data were obtained via the electronic medical record. He growth rate was calculated for all patients with radiological follow-up.

RESULTS

The cohort consists of 331 patients with 338 RAAs. Most patients were female (61.3%), with 11 (3.3%) of childbearing age. The mean age at diagnosis was 71.5 years (range, 24-99 years). Medical comorbidities included hypertension (73.7%), prior smoking (34.4%), and connective tissue disease (3.9%). Imaging indications included abdominal pain (33.5%), unrelated follow-up (29.6%), and follow-up of an RAA initially diagnosed before the study period (10.7%). Right RAA (61.9%) was more common than left (35.1%); 3% of patients had bilateral RAA. The mean diameter at diagnosis was 12.9 ± 5.9 mm. Size distribution included lesions measuring less than <15 mm (69.9%), 15 to 25 mm (27.1%), and more than 25 mm (3.0%). Anatomic locations included the distal RA (26.7%), renal hilum (42.4%), and mid-RA (13.1%). The majority were true aneurysms (98%); of these, 72.3% were fusiform and 27.7% were saccular. Additional characteristics included calcification (82.2%), thrombus (15.9%), and dissection (0.9%). Associated findings included aortic atherosclerosis (65.6%), additional visceral aneurysms (7.3%), and abdominal aortic aneurysm (5.7%). The mean clinical follow-up among 281 patients was 41.0 ± 24.0 months. The mean radiological follow-up among 137 patients was 26.0 ± 21.4 months. Of these, 43 patients (31.4%) experienced growth, with mean growth rate of 0.23 ± 4.7 mm/year; the remainder remained stable in size. Eight patients eventually underwent intervention (5 endovascular), with the most common indications including size criteria (4/8) and symptom development (3/8). No patient developed rupture. On multivariate analysis, obesity (P = .04) was significantly associated with growth. An initial diameter of more than 25 mm was significantly associated with subsequent intervention (P = .006), but was not significantly associated with growth. Four of five RAAs with an initial diameter 30 mm or greater did not undergo intervention. The mean clinical follow-up for these patients was 24 months; none developed rupture and two remained stable in size.

CONCLUSIONS

This large institutional cohort found that the majority of RAAs remained stable in size, with few patients meeting indications for repair based on societal guidelines. Current guidelines recommending intervention for asymptomatic aneurysms more than 30 mm seem to be appropriate given their slow progression.

A case report of multiple renal aneurysms due to Klippel-Trenaunay syndrome requiring laparoscopic nephrectomy

INTRODUCTION

Klippel-Trenaunay Syndrome (KTS) is a rare genetic disorder which is characterised by vascular nevi, venous varicosity, and hyperplasia of soft tissue or bone. Renovascular involvement is considered uncommon in KTS.

PRESENTATION OF CASE

A 79-year-old man presented with a left sided varicocele, lymphedema, hydrocele, and microscopic haematuria. After a series of investigations his imaging and clinical features were suggestive KTS. His images, which showed a 2.7 cm renal artery aneurysm, were discussed in the multi-disciplinary team (MDT) meeting and the decision was made to proceed with a laparoscopic nephrectomy.

DISCUSSION

Given the size of the aneurysm, treatment was offered and accepted by the patient. This is first recorded case in the literature in which a successful laparoscopic nephrectomy has been carried out for preventing severe haemorrhage in KTS. The patient presented in his 7th decade with a varicocele which would be considered unusual for KTS. Like in many cases, the renal artery aneurysm was asymptomatic. Pathological outcomes of the sample confirmed features suggestive of KTS, thus, validating the radiological findings.

CONCLUSION

Here, we report a favourable outcome of a patient referred for consideration of varicocele management, diagnosed with renal artery aneurysms on a background of KTS. KTS, with significant renovascular abnormalities, can be treated with laparoscopic nephrectomy. Careful discussion in MDT with regards to management options should be performed and a shared decision reached with the patient with regards to management. Though rare, patients presenting with varicoceles and lymphedema may have underlying capillary-lymphatic-venous malformations.

Blood pressure and renal outcomes after renal artery aneurysm intervention: Single-center experience and review of literature

Objective

To explore the results of hypertension improvement and renal function preservation after renal artery aneurysm (RAA) repair.

Methods

This study retrospectively analyzed the change in blood pressure (BP) and renal outcomes of 59 RAA patients throughout either open or endovascular operations and follow-up at a large center. Patients were grouped according to the difference in their BP at the last follow-up vs. their baseline value. Logistic regression was conducted to explore risk factors for perioperative BP relief and long-term hypertension reonset. Previous studies of RAA with records of BP, blood creatinine level, or GFR/eGFR results are reviewed.

Results

Hypertension was observed in 62.7% (37/59) of the patients included. Postoperative BP declined from 132.20 ± 16.46/79.92 ± 9.64 mmHg to 122.41 ± 11.17/71.10 ± 9.82 mmHg, while eGFR changed from 108.17 ± 24.73 to 98.92 ± 23.87 ml/min/1.73 m². The median follow-up was 854 [IQR: 1,405] days. Both open and endovascular techniques significantly relieved hypertension and did not impair renal function much. Lower preoperative systolic BP (SBP) was significantly associated with hypertension relief (OR = 0.83, 95% CI: 0.70-0.99). Among patients with normal BP after the operation, higher postoperative SBP was significantly associated with new-onset hypertension (OR = 1.14, 95% CI: 1.01-1.29). Literature review indicated that renal function usually remained normal at follow-up, whereas relief of hypertension varied.

Conclusion

Patients with lower preoperative SBP were likely to benefit more from the operation, while higher postoperative SBP indicated a higher chance of hypertension reonset. Creatinine level and eGFR generally remained stable regardless of operation type.

Utilizing 3D printing to facilitate surgical in-situ paediatric renal artery aneurysm repair for refractory hypertension

Renal artery aneurysmal (RAA) disease is a rare, but potentially life-threatening cause of renovascular disease presenting with hypertension. Conventional management involves aneurysmal excision followed by renal auto-transplantation. We present the management of a 13-year-old girl with complex multiple saccular aneurysmal disease of the left renal artery with hilar extension and symptomatic hypertension. We used 3D printing to print a patient-specific model that was not implanted in the patient but was used for surgical planning and discussion with the patient and their family. Endovascular options were precluded due to anatomical complexities. Following multi-disciplinary review and patient-specific 3D printing, she underwent successful in-situ RAA repair with intraoperative cooling, without the need for auto-transplantation. 3D printing enabled appreciation of aneurysmal spatial configuration and dimensions that also helped plan the interposition graft length needed following aneurysmal excision. The models provided informed multidisciplinary communications and proved valuable during the consent process with the family for this high-risk procedure. To our knowledge, this is the first reported case utilizing 3D printing to facilitate in-situ complex repair of RAA with intra-hilar extension for paediatric renovascular disease.

Eighteen cases of renal aneurysms: Clinical retrospective analysis and experience of endovascular interventional treatment

Background

Development of endovascular interventional techniques gradually replaced traditional open surgery and has become the preferred treatment for renal aneurysms. This study aimed to analyze the clinical characteristics of renal artery aneurysm (RAA) and the safety and efficacy of intravascular interventional treatment.

Materials and Methods

We retrospectively analyzed the clinical characteristics and imaging data of 23 aneurysms in 18 patients with RAA. The technical success rate, complication rate, mortality rate, reintervention rate, and use of embolization materials were evaluated.

Results

In 18 patients with RAA (age, 32-72 years, average age, 52.2 ± 11.2 years), a total of 23 aneurysms were found (diameter 0.5-5.5 cm, average diameter 2.2 ± 1.4 cm). Among them, 11 cases (61.1%) were discovered accidentally, and the remaining patients were diagnosed due to the following major complaints: four cases (22.2%) presented low back pain, two (11.1%) were due to high blood pressure, and one (5.5%) had low back pain with gross hematuria. A total of 14 aneurysms in 13 patients received endovascular interventional therapy. The technical success rate of 13 patients with renal aneurysms was 100%. Three of the 18 patients were lost to follow-up, and the remaining were followed up for 4-89 months. There was no recurrence of the aneurysm or displacement of the stent or coil.

Conclusion

Endovascular treatment for RAA has a high success rate, low complication rate, and low reintervention rate. It has the advantage of less trauma and is flexible and more targeted for different types of renal aneurysms.

A novel NF1 mutation in a pediatric patient with renal artery aneurysm

BACKGROUND

Neurofibromatosis type 1 (NF1) is a neurocutaneous syndrome, due to heterozygous pathogenic variants in NF1 gene. The main clinical manifestations are multiple café au lait spots, axillary and inguinal freckling, cutaneous and plexiform neurofibromas, optic glioma, Lisch nodules and osseous lesions, such as sphenoid and tibial dysplasia. Vasculopathy is another feature of NF1; it consists of stenosis, aneurysms, and arteriovenous malformations, frequently involving renal arteries.

CASE PRESENTATION

We report on a 9-year-old girl with a novel mutation in NF1 gene and renal artery aneurysm, treated by coil embolization and complicated with hypertension.

CONCLUSION

Vasculopathy is a complication of NF1, affecting from 0.4 to 6.4% of patients with NF1. Among the vascular abnormalities, renal artery aneurysm is a rare manifestation, with only a few cases regarding adult patients and no pediatric reports described in current literature. The finding of a vascular abnormality in a specific site requires the evaluation of the entire vascular system because multiple vessels could be involved at the same time.

Contrast-enhanced magnetic resonance angiography for monitoring an embolized renal artery aneurysm: A case report and literature review

This case report describes a 69-year-old male patient with a renal artery aneurysm that was followed up with contrast-enhanced magnetic resonance angiography at 8 months after coil embolization treatment. Due to the disappearance of residual lumen with few metal artifacts, the therapeutic effect was satisfactory. At present, the indications for the treatment of renal artery aneurysms are still controversial and there are very few reports of postembolization images of renal artery aneurysms, with no criteria for reintervention and few reports for monitoring the embolized aneurysms. Further reports and research are still needed for the treatment of this rare disease.

Giant Renal Artery Aneurysm With Hydronephrosis and Severe Atrophy of the Renal Parenchyma: Case Report and Literature Review

Background:

It is known that renal artery aneurysms may lead to hydronephrosis, but utter shrinking of the renal parenchyma due to a giant renal artery aneurysm has not yet been reported. This report is of an 88-year-old woman with resistant hypertension, hydronephrosis, and renal atrophy due to a giant saccular aneurysm of the left renal artery.

Case Report:

The patient presented with 2 weeks of worsening low back pain on the left side and resistant hypertension. The discovery of a left flank mass on physical examination, lead to the ultrasound detection of a para-aortic mass and a cyst-like partially septate structure replacing the left kidney. Thereafter, a contrast-enhanced computed tomography scan revealed a giant saccular aneurysm of the left renal artery causing severe hydronephrosis with severe parenchymal thinning. The extreme parenchymal atrophy of the left kidney made it an unlikely culprit of resistant hypertension, therefore the interventional radiologist considered that an endovascular attempt to re-establish the patency of the left renal artery would have scarcely produced any benefit. Given the advanced age of the patient, the vascular surgeon considered that risk of a nephrectomy outweighed the benefit, in agreement with the patient’s unwillingness to accept an invasive intervention. Therefore, she was discharged with blood pressure lowering and pain relief medication and was thereafter lost to follow-up.

Conclusion:

To our knowledge, this is the most severe kidney parenchymal shrinking in association with a renal artery aneurysm reported in the literature.

Coil embolization of a complex renal artery aneurysm using a new scaffold (Comaneci) device – A case report

Advances in endovascular approaches have resulted in increasing utilization of minimally invasive techniques to treat visceral artery aneurysms including renal artery aneurysms (RAAs), with high rates of success. The basic endovascular approach to treating RAAs includes stent graft exclusion or coil embolization. Treatment of RAAs with wide necks or at the bifurcation of the main vessel is facilitated by scaffolding techniques, which have been previously described. These techniques have their limitations and cannot be used in all situations. We describe a scaffolding technique using the Comaneci device (Rapid Medical, Israel), a retrievable mesh device meant for intracranial treatment of wide neck or bifurcation aneurysms that we used to safely and successfully treat a 2 cm RAA.

Diagnosis of Renal Artery Aneurysm by Point-of-Care Ultrasound in the Emergency Department: A Case Report and Brief Review of the Literature

BACKGROUND

Renal artery aneurysm (RAA) is defined as a focal dilatation of ≥50% of the adjacent, disease-free artery. Although typically asymptomatic, RAA can lead to hypertension, hematuria, and rupture. The risk of rupture is higher in pregnant patients and may result in the death of the mother and the fetus. We describe a case of RAA discovered on point-of-care ultrasound (POCUS) in the emergency department.

CASE REPORT

A 46-year-old woman with no medical history presented to the emergency department with lower abdominal pain, vomiting, diarrhea, and increased urination. POCUS was performed to evaluate the cause of the patient's symptoms. This study revealed a 2.40 cm × 3.65 cm aneurysm in the right kidney. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Rupture of RAA occurs in 3% to 5% of cases. Mortality to both the mother and the fetus is particularly high in gravid patients. RAA may be mistaken for other renal entities such as prominent renal veins or hydronephrosis. Properly identifying this pathology via POCUS can lead to early intervention. © 2022 Elsevier Inc.

Renal Artery Aneurysms in the Inpatient Setting

BACKGROUND

The risk of rupture of renal artery aneurysms (RAAs) remains undefined. A recent paper from the Vascular Low-Frequency Disease Consortium (VLFDC) identified only 3 ruptures in 760 patients. However, over 80% of patients in the VLFDC study were treated at large academic centers, which may not reflect the pattern of care of RAAs nationwide. Thus, the purpose of this study was to evaluate the pattern of nonelective versus elective surgery requiring inpatient admission for RAAs, including nephrectomies, and their outcomes using a national database.

METHODS

The National Inpatient Sample (NIS) database from 2012 to 2018 was utilized. Patients with a primary diagnosis of RAAs were identified using ICD-9 and ICD-10 codes. Ruptured RAAs (rRAAs) were identified utilizing surrogate ICD codes. The primary outcome variables for this study were proportion of RAAs requiring non-elective surgery and in-hospital mortality.

RESULTS

A total of 590 inpatient admissions for RAA were identified with 554 procedures at 467 hospitals across the country. Of the 590 inpatient admissions, 380 (64.4%) admissions were deemed nonelective. There was an increasing proportion of nonelective admissions over the study period. The overall rate of nephrectomies was 7.1% (n = 42). In-hospital mortality rate for the cohort was 1.4% (n = 8) with no differences in in-hospital mortality in the elective versus nonelective setting (1.0% vs. 1.6%; P = 0.718). In the nonelective setting, patients requiring a nephrectomy (n = 23) had significantly higher rates of in-hospital mortality compared those not requiring a nephrectomy (8.7% vs. 1.1%, P = 0.045). rRAA (n = 50) patients had significantly higher in-hospital mortality compared to the remainder of the cohort (6.0% vs. 0.9%, P = 0.024). rRAA patients were also more likely to undergo a nephrectomy compared to the remainder of the cohort (16.0% vs. 6.3%, P = 0.019).

CONCLUSIONS

These data demonstrate that treatment of RAAs are primarily done in the nonelective setting with a high proportion of ruptures, which could continue to rise as the threshold for repair has decreased.

Endovascular interventions in main renal artery pathologies: an overview and update

Renal arteries are involved in a wide spectrum of pathologies including atherosclerosis, fibromuscular dysplasia, Takayasu arteritis, aneurysms, and aortic type B dissections extending into main renal arteries. They manifest as renovascular hypertension, renal ischemia, and cardiovascular dysfunction. The location of the renal arteries in relation to the abdominal aortic aneurysm is a critical determinant of interventional options and long-term prognosis. This article provides a comprehensive review of the role of interventional radiologists in transcatheter interventions in various pathologies involving the main renal arteries with analysis of epidemiology, pathophysiology, newer interventional techniques, and management options.

Endovascular Treatment of a Giant Renal Artery Aneurysm with High-Flow Renal Arteriovenous Malformation

Renal artery aneurysms (RAAs) are rare lesions with a prevalence of less than 1% in the general population. Renal arteriovenous malformations (AVMs) are rare lesions with an estimated incidence of less than 0.04%. The coexistence of these two clinical entities is extremely rare and narrows the available treatment options by endovascular or open surgery. We describe a case of a giant symptomatic RAA type III, which was combined with a high-flow renal AVM in the right kidney. Using two vascular plugs, the RAA was excluded successfully. The perfusion of the right kidney’s lower pole was preserved by implantation of two covered stents in the inferior segmental renal artery.

A rare case of concurrent proximal and hilar renal artery aneurysm with renal arteriovenous fistula

Renal artery aneurysm (RAA) and renal arteriovenous fistula are rare vascular pathologies with reported incidences of 0.3% to 1.0% and 0.04% in the general population, respectively. We describe a 61-year-old Caucasian man who presented to the hospital with symptoms of right flank pain. Imaging demonstrated a right RAA with concurrent hilar RAA and renal arteriovenous fistula. He ultimately underwent an open right nephrectomy, ligation of the fistula, and bovine patch repair of the aortic defect.

Arterial Aneurysm Localization Is Sex-Dependent

The aim of this study was to investigate sex-dependent aneurysm distributions. A total of 3107 patients with arterial aneurysms were diagnosed from 2006 to 2016. Patients with anything other than true aneurysms, hereditary connective tissue disorders or vasculitides (n = 918) were excluded. Affected arterial sites and age at first aneurysm diagnosis were compared between women and men by an unpaired two-tailed t-test and Fisher’s exact test. The study sample consisted of 2189 patients, of whom 1873 were men (85.6%) and 316 women (14.4%) (ratio m:w = 5.9:1). Men had considerably more aneurysms in the abdominal aorta (83.4% vs. 71.1%; p < 0.001), common iliac artery (28.7% vs. 8.9%; p < 0.001), internal iliac artery (6.6% vs. 1.3%; p < 0.001) and popliteal artery (11.1% vs. 2.5%; p < 0.001). In contrast, women had a higher proportion of aneurysms in the ascending aorta (4.4% vs. 10.8%; p < 0.001), descending aorta (11.1% vs. 36.4%; p < 0.001), splenic artery (0.9% vs. 5.1%; p < 0.001) and renal artery (0.8% vs. 6.0%; p < 0.001). Age at disease onset and further aneurysm distribution showed no considerable difference. The infrarenal segment might be considered a natural border for aneurysm formation in men and women suspected to have distinct genetic, pathophysiologic and ontogenetic factors. Screening modalities for women at risk might need further adjustment, particularly thoracic cross-sectional imaging complementation.

Calcified intrarenal aneurysm simulating urinary lithiasis

We describe the case of a female patient with calcification in renal topography, initially diagnosed as lithiasis in the left kidney, and later attributed to calcification of intrarenal vascular aneurysm. Next, we discuss the relevance of considering such an entity in the differential diagnoses of intrarenal calcifications before choosing any form of specific interventional treatment.

Endovascular therapy for distal hilar renal artery aneurysm: a case report and literature review

Renal artery aneurysm (RAA), a type of visceral aneurysm with atypical symptoms, is difficult to detect and is usually discovered incidentally by imaging examination. Hilar RAA (HRAA) represents a relatively rare subgroup of RAA that is located in the distal part of the renal artery, close to the renal parenchyma. We reported a 55-year-old woman with an HRAA measuring 19 mm × 20 mm × 20 mm. She underwent endovascular therapy with bare-metal stent implantation with nested coil embolization. She was discharged without complications. The uniqueness of this case is the aneurysm location, which was at the distal right renal artery, making it difficult to preserve the blood supply to the right kidney. The novelty of the minimally invasive technique was that this endovascular treatment not only eliminated the aneurysm, but also preserved the blood supply to the ipsilateral kidney. Endovascular therapy is effective in the management of HRAA.

Multimodality imaging review of focal renal lesions

Background

Focal lesions of the kidney comprise a spectrum of entities that can be broadly classified as malignant tumors, benign tumors, and non-neoplastic lesions. Malignant tumors include renal cell carcinoma subtypes, urothelial carcinoma, lymphoma, post-transplant lymphoproliferative disease, metastases to the kidney, and rare malignant lesions. Benign tumors include angiomyolipoma (fat-rich and fat-poor) and oncocytoma. Non-neoplastic lesions include infective, inflammatory, and vascular entities. Anatomical variants can also mimic focal masses.

Main body of the abstract

A range of imaging modalities are available to facilitate characterization; ultrasound (US), contrast-enhanced ultrasound (CEUS), computed tomography (CT), magnetic resonance (MR) imaging, and positron emission tomography (PET), each with their own strengths and limitations. Renal lesions are being detected with increasing frequency due to escalating imaging volumes. Accurate diagnosis is central to guiding clinical management and determining prognosis. Certain lesions require intervention, whereas others may be managed conservatively or deemed clinically insignificant. Challenging cases often benefit from a multimodality imaging approach combining the morphology, enhancement and metabolic features.

Short conclusion

Knowledge of the relevant clinical details and key imaging features is crucial for accurate characterization and differentiation of renal lesions.

Multimodal repair of renal artery aneurysm-10-year single center experience

OBJECTIVES

Renal artery aneurysm (RAA) is a rare disease with various treatment options in indicated patients. In the current survey, the ten-year experience in treatment of RAAs using different endovascular and surgical treatments depending on RAA characteristics is discussed.

METHODS

All patients undergone RAA treatment via endovascular or surgical approaches at our center between January 2010 and December 2020 were enrolled. Patient demographics and peri-operative and late results were collected from a prospectively maintained database.

RESULTS

Eleven patients with RAA underwent treatment as follows: four patients received endovascular approach, four patients underwent in-situ RAA repair, and kidney autotransplantations were carried out in three patients. In all three treatment groups, the first therapeutic attempt was successful and none of the patients underwent secondary intervention due to RAA. Kidney autotransplantation was associated with a higher blood loss and a longer time of procedure compared to that of endovascular approach and in-situ repair. In-hospital postoperative complications were reported in five patients, including renal pole perfusion defect, renal artery thrombosis, and urinary tract infection. No acute kidney organ loss was seen, but one patient suffered from chronic kidney loss due to renal artery occlusion. In one patient undergoing autotransplantation, ureter anastomosis was reported, which led to acute renal failure, and a surgical treatment with resection and reanastomosis of the ureter was necessary. Hypertension was not resolved after RAA repair in any of the patients with preoperative hypertension.

CONCLUSIONS

RAA treatment selection depends on patient characteristics, anatomy, location, and arising branches of the aneurysm. In cases with complex anatomy, treatment strategy could not be just decided based on consensus guidelines, but a multidisciplinary team is required. Interventional therapies showed excellent results in non-complicated proximal aneurysms, especially regarding the length of hospital stay and postoperative morbidities. Open surgery is a complementary alternative in cases where minimally invasive therapy is not possible. Ex-situ repair with autotransplantation could be considered for anatomically complex distal aneurysms.

Kidney Autotransplantation for Renal Artery Aneurysm: Case Series and a Systematic Review

OBJECTIVES

Renal artery aneurysm (RAA) is a rare vascular disease. Kidney autotransplantation (KAT) is the treatment option when endovascular approach is not available. However, the evidence on KAT for RAA is mostly limited to small case series or reports. Here, we describe our 2 center experience of KAT for RAA, and provide the results of our systematic literature review to evaluate the outcomes.

METHODS

A retrospective 2 center study was conducted in patients undergoing KAT for RAA between 2010 and 2018. Moreover, a systematic review was performed on medical databases to evaluate the outcomes of KAT for RAA.

RESULTS

Nine patients were surgically treated at our institutions: eight with laparoscopic nephrectomy (LN), and 1 with open followed heterotopic KAT. All RAAs were ex-vivo reconstructed, and in 3 cases a vein graft was used for reconstruction. There were 2 postoperative major complications including 1 graft loss. In the systematic review, 102 studies with 355 patients were included. In 35 patients (9.9%) a minimal invasive approach was performed. The incidence of postoperative major complications and graft loss was 9.4% and 4.1%.

CONCLUSIONS

Our experiences showed that laparoscopic approach for nephrectomy followed heterotopic KAT was feasible with good postoperative outcomes. KAT is an effective treatment for RAA when endovascular approach is not feasible for interpretation of the outcomes, the quality and sample size of the evidence should be taken into consideration.

Renal autotransplantation for the treatment of renal artery aneurysm

OBJECTIVE

Renal artery aneurysms are a rare condition; however, the rate of diagnosis has been increasing, because of the increasing use of complementary diagnostic methods. The best treatment strategy for RAAs remains controversial. Data on ex-vivo surgery associated with kidney autotransplantation are scarce. As a result, the goal of this study was to describe this technique and to report our results.

METHODS

A retrospective monocentric study was undertaken using the clinical records and images of 35 patients diagnosed with renal artery aneurysm from 01/01/2010 to 31/12/2018. Indications for ex vivo surgery and autotransplantation were complex aneurysms with diameter >20 mm or rapid growth or symptomatic aneurysms or women wishing to become pregnant. Complex aneurysms were defined by anatomical criteria (bifurcation of the renal artery and its primary branches or hilar aneurysms) and/or physiological criteria (when time of warm ischemia in in-situ reconstruction is expected to last more than 45 minutes). The technique of ex-vivo surgery and autotransplantation consists of performing a nephrectomy, renal cooling, treatment of aneurysm in banking and implantation of the kidney in the homolateral iliac fossa.

RESULTS

A total of 35 patients with 56 renal artery aneurysms (26 women, mean age 52.4 years-minimum and maximum 16 and 74 years) were included. Of these, 27 were treated by surgery and 8 were followed clinically. Among those treated surgically, 24 performed ex vivo surgery associated with autotransplantation. Regarding ex vivo surgery, nephrectomy was performed by laparoscopic surgery in 24 of the 27 surgeries, the mean surgical time was 5.3 hours, the median warm ischemia time was 4 minutes and the length of hospital stay was 12.2 days. Mortality was 0% and the kidney patency rate was 93% with a follow up of 47.2 months. Of the 17 patients with hypertension, 6 cured it, 4 improved and 7 maintained hypertension.

CONCLUSION

Kidney autotransplantation appears to be efficient for most complex RAA with the possibility to minimize surgical aggression by performing laparoscopic nephrectomy.

Successful Prophylactic Embolization of a Renal Artery Aneurysm During Pregnancy

Renal artery aneurysms (RAA) have an increased risk of rupture during pregnancy with high mortality rates for the mother and fetus. There are many reports on the treatment of ruptured RAA during pregnancy and the Society for Vascular Surgery recommends to prophylactically treat unruptured RAA of any size in women of reproductive age to limit risk of rupture during pregnancy. However, to the best of our knowledge, there is no reported case of prophylactic treatment of unruptured RAA during pregnancy. Here we report the case of a 39-year-old G2P1 who had prophylactic endovascular coiling of an unruptured left RAA during her second trimester of pregnancy. Our case report is the first to demonstrate that unruptured RAA can be safely intervened endovascularly to prevent rupture without disrupting the pregnancy.

Single Centre Experience in Open and Endovascular Treatment of Renal Artery Aneurysms

BACKGROUND

The true incidence and natural history of renal artery aneurysm (RAA) remain unclear and still exists controversy over indication for treatment. Several techniques of conventional surgical reconstructions are described in literature, and more recently endovascular therapies have been reported with satisfying results and lower complication rate. This paper aims to investigate the outcomes of both endovascular and open repair of RAA achieved in a single institution involving 3 medical teams (urology, vascular surgery and neuroradiology).

MATERIAL AND METHODS

We conducted a single-centre retrospective observational study about all patients surgically or endovascularly treated for RAA over a 15-year period. Pre-operative, procedural and post-operative data at the early, mid- and long-term follow-up were collected and analysed, focusing on operative technique used for repair and related outcomes.

RESULTS

A total of 27 patients (n = 17 (63%) women, mean age 58 ± 13.2, n = 26 saccular RAA) were included. Mean aneurysm was size was 18.8 ± 6.3 mm. Most diagnosis were accidental. Symptomatic RAA showed with macroscopic haematuria (n = 3, 25.9%), unstable hypertension (n = 2; 7%), chronic lumbar pain (n = 1, 3.7%) and renal infarct (n = 1, 3.7%). Conventional surgery (ex-vivo repair, aneurysmorraphy, aneurysm resection and end-to-end anastomosis) was performed in 14 (51.8%) cases and endovascular coiling embolization in 13 (48.2%). Mean hospital length of stay was 5.4 ± 3.6 days. Intensive Care Unit stay was needed only in the surgically treated patients (mean 1.1 ± 1.2 days). During the early follow-up, morbidity rate was 7/14 in surgically treated patients vs. 1/13 in endovascular group; it included bleeding, retroperitoneal hematoma, arterial thrombosis and bowel obstruction. The discharge imaging showed complete aneurysm exclusion and renal artery patency in all cases. At a mean follow-up of 39 ± 42 months, 3 patients (11%) were lost to follow up and 2 (7.4 %) died from unrelated cause. None of these patients required dialysis but a statistically significant (P = 0.09) decrease in GFR was noted between the preoperative period and last follow-up control. RAA repair neither showed blood pressure control improvement nor reduced the need for anti-hypertensive drug use.

CONCLUSION

Open or endovascular techniques are both safe and efficient to treat RAA. Even though, surgical management is burdened with higher morbidity rate, the operative technique should be selected according to anatomical features, diameters and location of RRA; and the number of renal branches involved. Further larger studies are needed to define the feasibility and safety for a wider application of the endovascular approach.

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.

Morbidity and mortality associated with open repair of visceral aneurysms

BACKGROUND

The Society for Vascular Surgery (SVS) recently published clinical practice guidelines on the management of visceral aneurysms. However, studies investigating the perioperative outcomes of open repair of visceral aneurysms have been limited to single-center experiences with variable results that span multiple decades. In the present study, we sought to detail the morbidity and mortality associated with open repair of visceral aneurysms using a national database in the contemporary era.

METHODS

National Surgical Quality Improvement Program data from 2013 to 2019 were queried for patients who had undergone open repair of visceral aneurysms, which had been classified as mesenteric, renal, or splenic using Current Procedural Terminology and International Classification of Diseases codes. The primary endpoint was the composite of major complications (cardiovascular, pulmonary, progressive renal failure, deep wound infection, return to operating room, sepsis) and 30-day mortality. Logistic regression was used to identify the predictors of the primary endpoint for nonruptured aneurysm cases.

RESULTS

Of the 304 aneurysms, 263 were nonruptured (137 mesenteric, 66 renal, 60 splenic) and 41 were ruptured (24 mesenteric, 1 renal, 16 splenic) and had undergone open repair. For those with nonruptured aneurysms, their mean age was 59.4 ± 14.7 years and 48.3% were women. For those with nonruptured aneurysms, the 30-day mortality was 1.9% and the major complication rate was 12.9%. A return to the operating room (5.3%) and prolonged ventilator support (3.8%) were especially common. As expected, rupture was associated with significantly greater mortality (22.0%; P < .001) and major complications (34.1%; P = .001). The use of postoperative transfusion was common in the elective group but was significantly greater in the ruptured group (24.3% vs 80.5%; P < .001). The predictors of the primary outcome for nonruptured aneurysms included male sex (odds ratio [OR], 2.93; 95% confidence interval [CI], 1.28-6.7; P = .011), anticoagulation (not discontinued before surgery) or bleeding disorder (OR, 4.52; 95% CI, 1.37-14.7; P = .012), and albumin <3.0 g/dL (OR, 4.66; 95% CI, 1.17-18.6; P = .029). Neither age nor aneurysm location were significant risk factors.

CONCLUSIONS

Open repair of visceral aneurysms was associated with acceptable morbidity and mortality, although these risks are significantly greater once ruptured. Male sex, bleeding risk, and low albumin were all risk factors for adverse events and should be considered for operative planning and postoperative care.

Endovascular treatment of wide-necked aneurysms of the visceral and renal arteries using the double microcatheter technique via a single access route

PURPOSE

We aimed to evaluate the utility of and complications associated with the double microcatheter technique for the treatment of wide-necked visceral and renal artery aneurysms (VRAAs).

METHODS

Nine patients (mean age, 58 years; age range, 42-69 years; 4 men, 5 women) with wide-necked VRAAs who underwent treatment with the double microcatheter technique from January 2016 to July 2018 were included in the study. For all patients, anatomical features were confirmed using cone-beam computed tomography (CT) with rotational angiography. The aneurysmal location, size, volume, neck-to-dome ratio, number of coils used, and coil packing density were investigated. Technical success, complications (coil migration and organ ischemia), changes in the complete blood count or serum creatine level, and recurrence were also evaluated.

RESULTS

Three renal artery aneurysms and 6 splenic artery aneurysms were treated by the double microcatheter technique. The mean size of the aneurysms was 26.09±4.76 mm, mean volume was 6.19±3.69 cm3, and mean neck-to-dome ratio was 1.53±0.24. The number of coils used ranged from 7 to 16. The mean packing density was 11.32%±3.72%. Technical success was achieved in all 9 patients. Renal ischemia occurred in two patients with renal artery aneurysm, one of whom showed minimal scar formation on follow-up CT after infarction. No coil migrations or disease recurrences were observed.

CONCLUSION

The double microcatheter technique for the treatment of wide-necked VRAAs appears to be relatively safe and useful. However, complex renal artery aneurysm should be carefully managed in order to prevent infarction.

Endovascular management of a large renal artery aneurysm: a case report and review of the literature

Background

A renal artery aneurysm is a rare clinical presentation that can be found incidentally on imaging or during workup for refractory hypertension. Its presentation can be similar to that of a renal artery pseudoaneurysm, but the etiologies of the two vascular lesions differ. We present a patient who had an incidental finding of a large renal artery aneurysm that was managed with endovascular embolization. We also describe the literature surrounding the etiology, presentation and management of both renal artery aneurysms and renal artery pseudoaneurysms.

Case presentation

A 62-year-old man was referred to a urologic oncologist for workup of a newly found renal mass. Initial imaging with computed tomography showed a homogenous, well-circumscribed mass arising from the right kidney. Further evaluation with Doppler ultrasonography demonstrated pulsatile flow within the renal mass that was concerning for a renal artery pseudoaneurysm. The patient initially underwent a diagnostic angiogram by interventional radiology and was found to have a true renal artery aneurysm. Interventional radiology considered placement of a covered stent or angioembolization, but treatment was deferred due to concern for compromising the patient’s renal function. Patient was subsequently transferred to a neighboring hospital for management by vascular surgery. After considering both open surgical and endovascular approaches, the patient ultimately underwent angioembolization of the renal artery aneurysm. Short-term follow-up showed successful exclusion of the aneurysm with minimal adverse effects to the patient.

Conclusions

Our case report documents a unique case of an incidentally found large renal artery aneurysm that was successfully managed with endovascular embolization. Renal artery aneurysms and renal artery pseudoaneurysms, which can present similarly on imaging, are important diagnostic considerations in a patient presenting with a new renal mass. While open surgical approaches can be used to repair aneurysms, endovascular approaches using stenting or angioembolization are safe and effective options for treating renal aneurysms and renal pseudoaneurysms.

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.