Endovascular repair of abdominal aortic aneurysms in patients with congenital renal vascular anomalies

Horseshoe kidney: Morphologic features, embryologic and genetic etiologies, and surgical implications

The horseshoe kidney (HSK) is the most common congenital abnormality of the upper urinary tract with an incidence of approximately 1 in 500 in the general population. Although individuals with HSK are often asymptomatic, they are at increased risk for neoplasms, infections, ureteropelvic obstruction secondary to lithiasis or vascular compression. Direct injury from trauma is increased in these individuals as is the risk of intraoperative complications secondary to damage involving the typically complex renal or adrenal vascular supply. We briefly review etiological factors including renal and urinary system embryology, genetic mutations, abnormalities related to faulty cell signaling, aberrant cell migration, and other possible causes including environmental exposures and trauma. In addition, we call attention to factors that might influence the success of surgical procedures in patients with HSK. We argue that an understanding of possible etiologies of the HSK and its different subtypes may be useful when planning surgical procedures or considering risk-benefit ratios associated with different surgical options. We briefly present the organization of a HSK in a 100-year-old male demonstrating an unusual vascular supply discovered during a dissection laboratory session in a medical school anatomy course. We describe the structure of the HSK, the position and relationships of the HSK to other structures within the abdomen, and the associated vascular relationships.

Coexistence of Riedel’s Lobe and Supernumerary Kidney as Random Imaging Findings

Supernumerary kidney (SNK) is a rare congenital anatomical variation usually detected incidentally via imaging. Although a random finding, it may present with hydronephrosis, calculi or malignancy. Both its vascularization and its drainage vary significantly, depending on its location and shape. Riedel’s lobe is a normal, though rare, variant of liver anatomy presenting either as a downward projection of the inferior border of the right liver lobe or as a triangular pyramidoid projection to the right of the gallbladder.

We present a case of a 71-year-old man who was initially admitted to the hospital for backache. Computed tomography (CT) imaging revealed the simultaneous occurrence of a left supernumerary kidney and Riedel’s lobe. The SNK lay caudally to the normal kidney, it was supplied by a branch of the superior mesenteric artery and its drainage was supported by a bifid ureter. The Riedel’s lobe represented the “tongue-like” variant without causing any symptoms to the patient.

Both entities should be monitored carefully, as their presence may require surgical management should they raise a sequence of symptoms or, as in this case, modify the surgical plans in the context of other coexisting medical events.

Fenestrated endovascular abdominal aortic aneurysm repair with concomitant horseshoe kidney

Horseshoe kidney, representing abnormal fusion of the inferior renal poles, is a rare anatomic anomaly posing challenges in the setting of surgical abdominal aortic aneurysm repair. Historically, open repair has been the favoured surgical approach. However, due to the location of the renal isthmus and wide-ranging variation in anomalous renal vasculature, endovascular aneurysm repair (EVAR) has emerged as a popular, less invasive alternative. We describe one of the first published cases of two-fenestration EVAR in a patient with concomitant horseshoe kidney, followed by a discussion of current trends in surgical management. With the increasing availability to customise fenestrated grafts to patients' unique anatomy, this advanced EVAR technique may emerge as the preferred approach in certain cases.

Endovascular stent graft repair with chimney technique of an abdominal aortic aneurysm with concomitant horseshoe kidney

A 68-year-old male patient was referred to our clinic for treatment of an infrarenal abdominal aortic aneurysm. Computed tomography angiography revealed a horseshoe kidney overlying the aneurysm. The patient had an accessory renal artery arising from the anterior aspect of the aneurysm. Endovascular aneurysm repair was performed and the accessory renal artery could be revascularized successfully by chimney technique without any morbidity. Postoperative computed tomography angiography revealed complete exclusion of the aneurysm with no endoleak and a patent chimney graft.

Outcomes of Small Renal Artery Targets in Patients Treated by Fenestrated-Branched Endovascular Aortic Repair

OBJECTIVE

The aim was to evaluate renal related outcomes in patients who had incorporation of a small (<4.0 mm) renal artery (RA) during fenestrated-branched endovascular aortic repair (F-BEVAR).

METHODS

A total of 215 consecutive patients enrolled in a prospective F-BEVAR trial were reviewed. Computed tomography angiography centreline of flow reconstruction was used to measure mean RA diameter. Patients who had at least one <4.0 mm main or accessory RA incorporated by fenestration or directional branch (study group) were compared with patients who had incorporation of two ≥5.0 mm RAs (control group). Endpoints were technical success of RA incorporation, RA rupture and kidney loss, primary and secondary RA patency, RA branch instability and re-interventions, and renal function deterioration.

RESULTS

Twenty-four patients with 28 <4.0 mm RAs (16 accessory and 12 main RAs) were compared with 144 patients with 288 ≥5.0 mm incorporated RAs. Study group patients were significantly younger than controls (72 ± 8 vs. 75 ± 8 years, p = .04) and more often females (46% vs. 21%, p = .018); there were no differences in cardiovascular risk factors and aneurysm extent. Technical success was 92% for <4.0 mm and 99% for ≥5.0 mm RA incorporation (p = .05). Inadvertent RA rupture occurred in three patients in the study group (13%) and in one (1%) in the control group (p = .009) resulting in kidney loss in two study group patients (8%) and one (1%) control group patient (p = .05). At one year, primary patency was 79 ± 9% vs. 94 ± 1% (p < .001) and secondary patency was 84 ± 8% vs. 97 ± 1% (p < .001) for study vs. control group; freedom from branch instability was 79 ± 9% vs. 93 ± 2% (p = .005), respectively. There were no differences in re-intervention rates and renal function deterioration between the groups. The mean follow up time was 21 ± 14 months.

CONCLUSION

Incorporation of <4.0 mm RAs during F-BEVAR is associated with lower technical success, higher risk of arterial disruption and kidney loss, and lower patency rates at one year.

Successful para-aortic lymph node dissection for endometrial cancer with horseshoe kidney: A case report and review of the literature

Horseshoe kidney (HSK) is considered to impede para-aortic lymph node dissection. We report the case of a 54-year-old female patient with endometrial cancer and HSK, treated successfully with para-aortic lymph node dissection, and present literature review regarding vascular abnormalities associated with HSK affecting para-aortic lymph node dissection. Three-dimensional computed tomography reconstruction revealed the accessory renal artery, supernumerary renal vein and ventral displacement of the renal pelvis and ureter. Abdominal modified radical hysterectomy, bilateral salpingo-oophorec'tomy, pelvic and para-aortic lymph node dissection and omentectomy were then performed. Lymphadenectomy behind the isthmus of the kidney was performed without separation of the isthmus by lifting the kidneys with vessel tape. There were no intraoperative or postoperative complications. Grasping shifted ureter and complicated vascular network of HSK and securing the operative field without division of the isthmus were key to reducing complications and hemorrhage. This case report can serve as a guide for performing para-aortic lymph node dissection safely and effectively in patients with HSK.

Diameters of Arteries Supplying Horseshoe Kidneys and the Level They Branch off Their Parental Vessels: A CT-Angiographic Study

Background: The most common renal fusion anomaly is horseshoe kidney (HSK), a condition associated with variable arterial blood supply. The aim of this study was to determine whether the height of origin of the renal artery determines its diameter and whether it differs from the mean diameter of the renal arteries of normal kidneys (NK). Methods: Computer tomography angiography (CTA) studies of 336 patients (88 HSK and 248 NK) were obtained in a search of renal arteries; these were than classified into four groups according to height of its origin: Group I, branching from the aorta superior to the inferior mesenteric artery (IMA); Group II, branching from the aorta below the IMA; Group III, branching from the iliac artery; and Group IV, originating from the internal and external iliac artery. Results: The HSK group included 398 arteries (mean diameter 4.30 mm) and the NK group 598 (5.52 mm) (p < 0.0001). In the HSK group, the mean diameters according to groups were: Group I, 4.54 mm; Group II, 4.28 mm; Group III, 3.41 mm; and Group IV, 3.43 mm. Statistically significant differences were found between arteries originating from the aorta and arteries branching from the iliac arteries (p < 0.0001). In the NK group, the corresponding values were: Group I, 5.53 mm; and Group II, 4.45 mm. The number of arteries supplying the HSK wider than 3.0 mm were: Group I, 83.0%; Group II, 82.4%; Group III, 68.4%; and Group IV, 66.6%. Conclusions: The renal arteries of the HSK branch from their parental vessels at lower levels and have smaller diameters than those of NK.

EVAR Approach for Abdominal Aortic Aneurysm with Horseshoe Kidney: A Multicenter Experience

BACKGROUND

Horseshoe kidney is a congenital abnormality, with an incidence of 0.25% of the total population. Only 0.12% of patients who undergo an abdominal aortic aneurysm repair might also have a coexisting horseshoe kidney. We present a series of 10 cases auspiciously treated with an endovascular approach along with their respective patient evolutions. A review of the literature is also presented.

MATERIALS AND METHODS

A retrospective review of the medical records (January 2004-December 2013) of 10 patients with abdominal aortic aneurysms and horseshoe kidney treated with endovascular repair was done. Patients were treated at 6 different centers in 3 different countries. Demographics, clinical status, medical history, anatomical morphology of the aneurysms and kidneys, as well as surgical outcomes were all analyzed.

RESULTS

The median age was 67.5 years (range 47-81), and the median aortic aneurysmal diameter was 57 mm (49-81 mm). A total of 35 arteries provided renal perfusion. There were 13 right renal arteries and 13 left renal arteries, all successfully preserved, with 9 isthmus arteries covered. Median hospital stay consisted of 3.5 days (1-14 days). All aortic aneurysms were successfully excluded with no endoleaks, hematomas, wound infections, or renal failure. During a median follow-up of 7 years, 3 patients died of myocardial infarction 7 years after endovascular aortic repair (EVAR), and the other 7 patients are doing well, with a median aneurysm reduction size sac of 16.5 mm.

CONCLUSIONS

Endovascular repair is a safe and efficient endovascular option for the treatment of patients presenting concomitant aortic aneurysm and horseshoe kidney, with excellent short- and medium-term outcomes. To our knowledge, our study represents the largest series of cases with horseshoe kidney successfully treated via EVAR without significant complications.

The level of origin of renal arteries in horseshoe kidney vs. in separated kidneys: CT-based study

Purpose

Horseshoe kidney is a rare congenital anomaly with potential clinical implications. The aim of this study was to determine the number of renal arteries and veins and the level at which the arteries branched off their parental vessels in individuals with horseshoe kidney (HSK) and in persons with separated kidneys (SK).

Materials and methods

The analysis included computed tomography angiography studies of 331 patients (83 HSK and 248 SK). The number of renal vessels and diameters of renal arteries were determined, along with the level at which they branched in relation to other ramifications (four groups of origin were proposed) and their entrance of the vessels to the kidney.

Results

Number of renal arteries in HSK group was 4.57 ± 1.39 per patient and 2.4 ± 0.43 in SK group (p < 0.0001). The distribution of branching level of renal arteries in HSK group was: I group ~ 57%, II group ~ 27%, III group ~ 15% and IV group < 1%, whereas in SK group the distribution was respectively: I group ~ 99%, II group < 1%, III and IV group − 0% (p = 0.0001). In HSK group, diameter of renal arteries branching above the IMA was 4.61 ± 1.58 mm, as compared with 3.96 ± 1.34 mm for the arteries branching below (p = 0.0004). Number of veins was 566 in SK group (87.70% of kidneys were supplied by single vein) and 323 in HSK group (9.64% kidneys were supplied by two veins) (p < 0.0001).

Conclusion

In HSK group, renal arteries significantly more often branch off their parental vessels below the origin of IMA and such vessels are usually smaller.

Coverage of Accessory Renal Arteries During Endovascular Aortic Aneurysm Repair: What Are the Consequences and the Implications for Clinical Practice?

An accessory renal artery (ARA) represents an anatomic variation which can challenge endovascular aortic aneurysm repair (EVAR). The aim of this review was to summarize the current knowledge on postoperative outcomes following ARA coverage during EVAR. We performed a systematic literature review. The MEDLINE database was searched on September 2017, and 8 relevant studies were included. The frequency of ARA in patients undergoing EVAR varied between 9.5% and 16.2%, and the frequency of ARA coverage varied between 5.2% and 9.4%. Four reports did not observe any significant changes on postoperative renal function, whereas 1 study reported an early transient increase in creatinine after ARA coverage. The occurrence of renal infarct varied from 20% to 84%. Five studies did not observe endoleaks related to ARA coverage, whereas one reported the occurrence of type II endoleaks in 3 of 18 patients who had ARA coverage. No significant change in blood pressure, mortality, and mean length of hospital stay was observed. The ARA coverage can potentially have renal and vascular consequences, but none of them were critical. Further studies may be useful to identify preoperative criteria that may help to choose the most appropriate surgical approach before ARA coverage.

Ruptured Abdominal Aortic Aneurysm in a Patient with Congenital Fused Pelvic Kidney: A Case Report of Emergency Endovascular Treatment

A 90-year-old male developed acute onset of abdominal and lumbar pain due to the rupture of an 11-cm abdominal aortic aneurysm. A congenital fused pelvic kidney perfused by three renal arteries arising from iliac axes was detected. In an emergent setting, an aorto-uni-iliac endograft was deployed through right femoral surgical access with occlusion of the upper right renal artery. An occluder device was placed in the common iliac artery above the renal artery through left femoral access. A femorofemoral crossover bypass completed the procedure. The patient developed acute renal failure, with no dialysis necessity. One-month computed tomography angiography showed procedure success.

Surgical Treatment of Abdominal Aortic Aneurysms Associated with Horseshoe Kidney

Abdominal aortic aneurysm surgery associated with a horseshoe kidney (HSK) is a serious technical challenge for the surgeon. We reviewed our experience with 127 patients electively operated on between 1990 and 2004 for abdominal aortic aneurysm. Pre- and perioperative medical, surgical, and radiologic data were retrospectively reviewed. Preoperative diagnosis was achieved with computed tomography with or without angiography or with additional conventional aortography.

Seven patients were recognized to have had a HSK, with a mean age of 67.29 ± 2.43 years. Preoperative serum creatinine levels were similar in patients with or without HSK (1.0 ± 0.08 vs 0.9 ± 0.12 mg/dL; not significant). In five of the patients with HSK, reimplantation of the anomalous renal artery was necessary. In all 127 patients, hospital mortality consisted of 5 patients, none of whom had an HSK. Dealing with HSK seemed to increase aortic clamp times (30.43 ± 3.55 vs 27.04 ± 3.92 minutes; p < .05) slightly. Patients with or without HSK were given similar amounts of intravenous fluid replacement (2,214.2 ± 441.3 vs 1,923.3 ± 433.6 mL/patient; not significant) and allogeneic blood transfusion (0.71 ± 0.49 vs 0.9 ± 0.4 U/patient; not significant) and had a similar intensive care unit stay.

Abdominal aortic aneurysms associated with HSK have been managed without division of the isthmic tissue. The left retroperitoneal approach provided adequate exposure for all patients with HSK.

Open Surgical Repair of Abdominal Aortic Aneurysm Coexisting with Horseshoe Kidney

Horseshoe kidney (HSK) is the most common congenital abnormality of the urologic system encountered during abdominal aortic aneurysm (AAA) surgery. Here, the authors report a case of AAA coexisting with HSK that was successfully treated by open surgery. Two accessory renal arteries of 2.5 mm and 3.1 mm were reimplanted. One of the implanted arteries later occluded and infarct of the isthmus developed, but there was no impairment of renal function. The authors discuss the complexity of the surgical treatment of AAA coexisting with HSK, and place focus on which accessory renal arteries should be reconstructed.

Preservation of the accessory renal arteries after endovascular repair of common iliac artery aneurysm using kissing stent grafts

Exclusion of the accessory renal arteries (ARAs) is required during endovascular aneurysm repair if they arise from the sealing zone or aneurysm sac. Here, we report a case of successful endovascular treatment for a common iliac artery aneurysm located close to the aortic bifurcation and associated with nephrotic syndrome in a 51-year-old man. The bilateral ARAs were successfully preserved using kissing stent grafts. During surgery, the proximal ends of endografts inserted from the bilateral femoral arteries were adjusted so that they met at the same level in the aorta, and simultaneous balloon dilatation was performed. This method can be a useful treatment option for common iliac aneurysms in cases with large ARAs.

Aortoiliac aneurysm with congenital right pelvic kidney

The association of congenital pelvic kidney with abdominal aortoiliac aneurysm is an extremely rare clinical finding. Previous reports have described various methods of aneurysm repair with successful preservation of the function of pelvic kidney. However, to our knowledge, reconstruction of more than two renal arteries has not been established. We report a case of abdominal aortic aneurysm complicated by congenital right pelvic kidney in a 72-year-old man. Computed tomography (CT) revealed an abdominal aortic aneurysm with a maximum diameter of 54 mm and a right common iliac aneurysm of 45 mm. In addition, he had a congenital right pelvic kidney and CT angiography identified three right pelvic renal arteries. The upper artery originated from the bifurcation of the terminal aorta and the lower two originated from the right common iliac artery. Three-dimensional CT was helpful for the accurate planning of the operation. Open surgical repair of the aortoiliac aneurysm with a Dacron bifurcated graft replacement was decided and reimplantation of all three right pelvic kidney arteries to the right limb of the graft was also performed. For renal preservation, the right pelvic kidney arteries were perfused with cold Ringer's lactate using a rapid infusion pump and coronary perfusion cannula. The patient's postoperative course was uneventful, and worsening of renal function was not observed. The perfusion of renal arteries with cold Ringer's solution was thought to be a simple and appropriate procedure for renal protection.

Customized fenestrated endovascular graft repair of abdominal aortic aneurysm with concomitant horseshoe kidney

The occurrence of an abdominal aortic aneurysm (AAA) with horseshoe kidney (HSK) is an uncommon but complex surgical problem. This report outlines three such cases, the particular issues encountered and how customized endovascular grafts were successfully used to overcome them. Case one shows an accessory renal artery arising from the left common iliac artery, case two shows a right accessory renal artery from the AAA sac and case three has the right renal artery coming off the distal abdominal aorta within the sac. Across three patients, each graft had a single custom fenestration, which preserved a total of three major vessels with no change in renal function. Customized endografts are a viable tool to preserve aberrant vessels and thus renal mass in AAA and HSK. Customized endografts require an extensive work-up and are currently expensive to fabricate. However they are rapidly evolving as a mainstream tool in vascular surgery and provide a solution in cases of aberrant visceral vasculature.

Tratamento endovascular de aneurisma de aorta abdominal em paciente com rim em ferradura: relato de caso

O rim em ferradura é uma das anomalias urológicas congênitas mais comuns e está presente em cerca de 0,12% dos pacientes com aneurisma de aorta abdominal. O reparo cirúrgico convencional está associado a dificuldades técnicas que provavelmente aumentam a morbidade e a mortalidade, mas que podem ser evitadas com o tratamento endovascular. Relatamos um caso de um paciente de 64 anos com rim em ferradura e aneurisma de aorta abdominal, que foi submetido ao reparo endovascular do aneurisma com sucesso.

Percutaneous endovascular repair of abdominal aortic aneurysm with coexisting horseshoe kidney: technical aspects and review of the literature

Surgical repair of abdominal aortic aneurysms (AAAs) with coexisting horseshoe kidney (HSK) is technically challenging because of complex anatomy. Endovascular repair has emerged as a common approach to AAA repair and represents a valid alternative in selected patients with AAA and concomitant congenital renal anomalies. We report a case of successful percutaneous endovascular repair in a patient with coexistent AAA and HSK. Careful preoperative planning is essential in successful endovascular management of abdominal aneurysms in these patients.

Left-sided and duplicate inferior vena cava: a case series and review

Left-sided and duplicate inferior vena cava (IVC) are two major anatomical variants within the spectrum of IVC malformations, both of which are developmental abnormalities of the supracardinal veins. Four clinical cases are described to highlight the computed tomographic appearances of these vascular malformations and provide novel data on venous dimensions. A systematic review of the recent literature (2000-2011) was conducted focusing on the anatomy, demographics, and associated pathology (congenital and acquired) of isolated left-sided and duplicate IVC. A total of 73 relevant articles were retrieved, consisting of case reports and small case series. The prevalence of left-sided IVC is about 0.1-0.4% and that for duplicate IVC about 0.3-0.4%; both anomalies show a slight male preponderance. In each condition, there are documented variations in the course and tributaries of the IVC. The clinical importance of these anomalies lies in three principal areas: the potential for misdiagnosis on imaging; technical difficulties during retroperitoneal surgery (particularly abdominal aortic aneurysm repair and live donor nephrectomy); and their significance in relation to the etiology and management of venous thromboembolism.

Endovascular repair of an abdominal aortic aneurysm in the presence of a hydronephrotic horseshoe kidney

The aim of this paper is to report an unusual case of a patient with an abdominal aortic aneurysm (AAA) and a hydronephrotic horseshoe kidney (HSK) that was repaired by endovascular means. An 81-year-old male patient with a known HSK was found to have hydronephrosis and an AAA. The patient's aneurysm was treated with an endovascular stent graft which required the covering of accessory renal arteries. He had an uneventful recovery with complete resolution of the hydronephrosis evident on a computed tomography scan performed seven months after the surgery. In conclusion, endovascular aneurysm repair is a feasible therapeutic option for an AAA coexisting with an HSK and may be considered as a valid alternative to open repair when concomitant hydronephrosis is present.

A unique case of a type II endoleak after EVAR caused by patent inferior mesenteric and accessory renal arteries

Type II endoleaks have been viewed as the Achilles' heel of endovascular repair of abdominal aortic aneurysms. This report describes a unique etiology to this common challenge and our approach to endovascular repair.

Endovascular infrarenal aneurysm repair in patients with horseshoe kidneys: case series and literature review

Horseshoe kidney may cause technical and access problems during open aortic aneurysm repair. The aim of this study is to report two cases from our institution and to review the world's literature on successful endovascular infrarenal aneurysm repair in patients with horseshoe kidneys. A retrospective review of a prospectively entered departmental computerized database was performed for the two patients from our institution. Articles were searched electronically from PubMed and Medline, using the terms ‘horseshoe kidney’ and ‘aneurysm’. Endovascular cases were reviewed from the world's literature. In addition to the two patients from our institution, there were 19 patients with infrarenal aneurysms and horseshoe kidneys in published literature who underwent successful endovascular aneurysm repair. The occlusion of lower-pole or accessory renal arteries does not seem to cause significant endoleak or renal impairment in the long run. In conclusion, our experience and current literature seem to suggest that endovascular repair of infrarenal aortic aneurysms for patients with horseshoe kidneys is safe. Renal impairment will depend on the area of kidney perfused by the accessory renal arteries. The endovascular treatment option is less invasive than open repair, and circumvents the problem of difficult exposure, especially in those patients with significant co-morbidity.

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.

A double shunt technique for the prevention of ischaemia of a congenital, solitary, pelvic kidney during abdominal aortic aneurysm repair: a case report

INTRODUCTION

Congenital solitary pelvic kidney is a rare condition, and its association with an abdominal aortic aneurysm is even more unusual. To the best of our knowledge, only two such cases have been reported in the literature to date.

CASE PRESENTATION

We report the case of a 59-year-old Caucasian man with a congenital solitary pelvic kidney, who was found to have an abdominal aortic aneurysm 83 mm in diameter. Abdominal computed tomography angiography clearly identified two renal arteries, one originating from the aortic bifurcation. and the other from the proximal portion of the right common iliac artery. At surgery, renal ischaemia was prevented by introduction of an axillofemoral shunt (consisting of two femoral cannulas and a vent tube of extracorporeal circulation) from the right axillary to the right femoral artery, and a second Argyle shunt from the right common iliac artery to the origin of the left renal artery. A 20 mm Dacron tube graft was then implanted. Our patient's postoperative renal function was normal.

CONCLUSION

The renal preservation double shunt technique used in this case seems to be effective during abdominal aortic aneurysm repair.

Horseshoe kidney and inflammatory abdominal aortic aneurysm: a case report and literature review

The combined presence of an inflammatory abdominal aortic aneurysm and a horseshoe kidney is a rare event with only one reported case in previously published data. We present a case of a horseshoe kidney with a concomitant 6-cm inflammatory abdominal aortic aneurysm and a 3.6-cm right iliac artery aneurysm repaired through a transperitoneal approach with aortoiliac reconstruction.

Abdominal aortic surgery and renal anomalies

Introduction. Kidney anomalies present a challenge even for the most experienced vascular surgeon in the reconstruction of the aortoilliac segment. The most significant anomalies described in the surgery of the aortoilliac segment are a horse-shoe and ectopic kidney. Objective. The aim of this retrospective study was to analyze experience on 40 patients with renal anomalies, who underwent surgery of the aortoilliac segment and to determine attitudes on conventional surgical treatment. Methods. In the period from 1992 to 2009, at the Clinic for Vascular Surgery of the Clinical Centre of Belgrade we operated on 40 patients with renal anomalies and aortic disease (aneurysmatic and obstructive). The retrospective analysis involved standard epidemiological data of each patient (gender, age, risk factors for atherosclerosis, type of anomaly, type of aortic disease, presurgical parameter values of renal function), type of surgical approach (laparatomy or retroperitoneal approach), classification of the renal isthmus, reimplantation of renal arteries and perioperative morbidity and mortality. Results. Twenty patients were males In 30 (70%) patients we diagnosed a horse-shoe kidney and in 10 (30%) ectopic kidney. In the cases of ruptured aneurysm of the abdominal aorta the diagnosis was made by ultrasound findings. Pre-surgically, renal anomalies were confirmed in all patients, except in those with a ruptured aneurysm who underwent urgent surgery. In all patients we applied medial laparatomy, except in those with a thoracoabdominal aneurysm type IV, when the retroperitonal approach was necessary. On average the patients were under follow-up for 6.2 years (from 6 months to 17 years). Conclusion. Under our conditions, the so-called double clamp technique with the preservation of the kidney gave best results in the patients with renal anomalies and aortic disease.

Technical Considerations for Transabdominal Aortic Reconstruction with Renal Fusion and Ectopia: Case Series

Aortic diseases associated with renal anomalies can present special challenges during surgery of the abdominal aorta. The aim of this paper is evaluation of morbidity and definition of optimal management according to the clinical histories of 30 patients with horseshoe and ectopic kidneys who underwent surgical procedures on the abdominal aorta over a 20-year period. Twenty-two of them had horsheshoe kidney and eight had ectopic kidney. Indications for surgery included aortic aneurysms in 25 patients and aortoiliac occlusive disease in 5. Preoperative diagnostics were performed in all cases by means of computed tomography and angiography (except in the cases with ruptures) associated with duplex ultrasonography. In patients with ectopic kidney a Carrel patch technique was used for the reimplantation of the renal arteries into the body of the bifurcated (four cases) or tubular (four cases) Dacron graft in five (62.5%) cases whereas aortorenal bypass with Dacron graft was obtained in three cases (37.5%). Sixteen patients from the horseshoe kidney group required renal revascularization (reimplantation using Carrel patch in 10 patients and aortorenal bypass using Dacron graft in 6 patients). Two patients, both with ruptured abdominal aortic aneurysms died after the operation. In other cases the average follow up period was 6.2 years (6 months to 17 years). In one case control, angiography after 6 months revealed an occluded left renal artery that was reimplanteted by Carrel patch but without repercusions on the renal function. Aortic surgery in patients with renal anomalies can be safely performed without increased mortality.

Anatomic variations of the renal vessels pertinent to transperitoneal vascular control in the management of trauma

BACKGROUND

Operative exposure and control of the renal vessels through a transabdominal retroperitoneal (TARP) approach has been advocated for emergency management of renal trauma. The pertinent anatomic variations of the renal vasculature have not been well described.

METHODS

In 190 cadavers, the renal vessels were examined. The first 20 cadavers were examined via TARP approach, and 170 cadavers were investigated after evisceration. The findings were interpreted as they might relate to the TARP approach to the renal pedicle.

RESULTS

The renal artery (RA) originated dorsally or inferiorly to the left renal vein (RV) in 70% of the cadavers on each side. Additional RAs emerging below the inferior mesenteric artery were present in 2.4% of cadavers on the right side and 1.8% on the left. Approach to the inferior vena cava (IVC) adequate for the management of trauma through the TARP approach was impossible, although it has been recommended in some research. The clinically significant incidence of variations was as follows: 47% multiple RAs, 13% multiple RVs, and 50% of at least 1 RA that coursed superior to the right RV on the right margin of the IVC.

CONCLUSION

Knowledge of the varied anatomy of the renal vessels facilitates a safe approach to the kidneys in trauma management. The varied and unpredictable anatomy of the renal vasculature requires prompt change when the TARP approach fails to provide access to the vessels. In such cases, the colon should be mobilized promptly. On the right side of the IVC, the vessels are located so as to require clamping together almost always.

Abdominal Aortic Aneurysm with Coexistent Horseshoe Kidney

Surgical repair of an abdominal aortic aneurysm (AAA) concomitant with a horseshoe kidney (HSK) may be technically demanding because of the complex anomalies of the kidney and of its collecting system and arteries, the greater risk of HSK-related complications, and the often unexpected intraoperative finding of HSK itself. We reviewed a database of more than 500 patients with AAA observed in our surgical department from 1994 to the time of writing. Five patients had AAA concomitant with HSK. Two of these patients did not undergo surgery because of the small dimension of the aneurysm or because of their poor health. The other three underwent successful repair of AAA with different techniques; namely, an aortobifemoral bypass via a thoracoabdominal retroperitoneal incision in one, a straight graft via an emergency median laparotomy in one, and an endovascular repair followed by open surgery 4 years later for endotension in one. Abnormal minor renal arteries were deliberately occluded and only one of these caused a minor renal infarct, but without functional impairment. These data and a review of the literature indicate that HSK should not preclude repair of coexistent AAA, as imaging procedures provide the information necessary to plan the best approach for each patient. Up-to-date surgical procedures, a posteriori retroperitoneal approach or endovascular repair, and deliberate occlusion of the minor renal arteries appear feasible and safe as they avoid most of the anatomical problems and provide results equivalent to those of uncomplicated aortic surgery.

Renal Function after Elective Infrarenal Aortic Aneurysm Repair in Patients with Pelvic Kidneys

Pelvic kidneys complicate aortic reconstructions because of increased risk of renal ischemia. Strategies for protection include shunting, cooling, and reliance on collaterals. A review identified two congenital pelvic kidney (not solitary) and five transplanted kidney patients who underwent elective abdominal aortic aneurysm repair. For congenital pelvic kidneys, topical cooling was used in one patient while no preservation was performed for the other patient. Three transplanted kidney patients were shunted, and one had endovascular repair. Postoperative creatinine values were compared to preoperative values. The two congenital pelvic kidney patients had no significant elevation of creatinine postoperatively. The transplanted kidney patient who underwent endovascular repair had no increase in creatinine postoperatively. All transplanted kidney patients who had open repair had significant but transient increase in creatinine postoperatively. Three patients who were shunted intraoperatively had normalization of creatinine. The patient who had persistent elevation of creatinine at discharge was not shunted. Aortorenal shunting or endovascular repair in transplanted pelvic kidney patients maintains renal function. For patients with congenital pelvic kidneys and adequate collaterals, cooling and collateral perfusion is usually sufficient. Though experience is limited, endovascular repair is likely to be superior to open repair in minimizing renal ischemia.

Endovascular Repair of an Abdominal Aortic Aneurysm in a Patient with Horseshoe Kidney: Report of a Case

A horseshoe kidney poses special problems during treatment of an abdominal aortic aneurysm (AAA), and there is much controversy about the most suitable method of repair. We report the case of a 65-year-old man with a horseshoe kidney, in whom an AAA was treated with a unibody bifurcated endograft. During the procedure, the two anomalous renal arteries were sacrificed. Although there was transient elevation of the creatinine levels, the patient was discharged with normal renal function and no endoleak from the accessory renal arteries. Thus, when two normal and two accessory renal arteries arise from the non-aneurysmatic proximal aortic neck, providing that preoperative kidney function is normal, it seems that the treatment can be safely carried out using an endovascular technique and excluding the accessory renal arteries. This case supports the feasibility of endovascular surgery for the treatment of AAA in the presence of a horseshoe kidney.

Outcomes of accessory renal artery occlusion during endovascular aneurysm repair

OBJECTIVE

Accessory renal arteries are frequently encountered when patients are evaluated for endovascular abdominal aortic aneurysm repair (EVAR). Some have considered their presence a contraindication to EVAR in fear of endoleak and the end result of renal function. We sought to determine whether the coverage of accessory renal arteries during EVAR was associated with any adverse sequelae.

METHODS

Retrospective review of the medical records and computed tomographic scans of all patients undergoing EVAR (1998 to 2003) was performed. Note was made of the presence or absence of accessory renal arteries, hypertension, and renal function. Preoperative computed tomographic images were compared with postoperative images to determine the presence of renal infarction. A control group of 26 consecutive patients without accessory renal arteries was used for comparison of the results of EVAR.

RESULTS

EVAR was performed in 550 patients over the study interval. The mean follow-up was 16 months (range, 1-48 months). The average age was 74 years (range, 57-90 years). Thirty-five patients (6.6%; 32 male and 3 female) were documented to have accessory renal arteries; the average number of accessory arteries was 2 (range, 1-4). Bilateral accessory arteries were present in 13 patients: all but 1 patient (n = 34) had a left-sided accessory renal artery, and 23 had a right-sided accessory renal artery. EVAR was performed with a variety of endografts: AneuRx (n = 10), Talent (n = 7), PowerLink (n = 7), Zenith (n = 5), LifePath (n = 4), and Ancure (n = 2). There were no mortalities. Twelve endoleaks were documented: three type I, eight type II, and one type III. The accessory renal arteries were not implicated in any of the endoleaks, and none of these accessory vessels was embolized before or after EVAR. Seven patients (20%) had renal infarcts associated with EVAR that were noted on follow-up computed tomographic scans. The mean follow-up for patients with segmental infarction was 23 months (range, 8-48 months). Hypertensive status did not change in any patient in whom an accessory renal artery had been covered. The average serum creatinine was 1.08 mg/dL (range, 0.6-1.8 mg/dL) before EVAR in patients with accessory renal arteries covered by an endovascular graft and did not change significantly in response to EVAR. Serum creatinine increased almost twofold in two patients but spontaneously resolved in follow-up. The average preoperative creatinine clearance was 79 mL/min (range, 35-166 mL/min) in patients without an accessory renal artery and was 80 mL/min (range, 35-167 mL/min) after EVAR. The average preoperative creatinine clearance was 67 mL/min (range, 31-137 mL/min) in patients with an accessory renal artery and 68 mL/min (range, 45-83 mL/min) in patients with renal infarcts. None of the patients required temporary or permanent dialysis. There was no difference between control patients and patients with covered accessory renal arteries with respect to hypertensive status, presence of renal infarcts, serum creatinine, or creatinine clearance after EVAR.

CONCLUSIONS

Occlusion of accessory renal arteries is not associated with clinically significant signs or symptoms, even in patients with mild or moderate renal insufficiency. Sacrifice of accessory renal arteries most commonly does not lead to detectable renal infarction, either clinically or radiographically. When segmental infarction of the kidney does result, it seems to be well tolerated in this group of patients. Accessory renal arteries were not found to contribute to endoleaks and should not be prophylactically embolized.

Transrenal fixation of aortic stent-grafts: current status and future directions

Aortic stent-graft repair has been widely used in clinical practice for more than a decade, achieving satisfactory results compared to open surgical techniques. Transrenal fixation of stent-grafts is designed to obtain secure fixation of the proximal end of the stent-graft to avoid graft migration and to prevent type I endoleak. Unlike infrarenal deployment of stent-grafts, transrenal fixation takes advantage of the relative stability of the suprarenal aorta as a landing zone for the uncovered struts of the proximal stent. These transostial wires have sparked concern about the patency of the renal arteries, interference with renal blood flow, and effects on renal function. Although short to midterm results with suprarenal stent-grafts have not shown significant changes in renal function, long-term effects of this technique are still not fully understood. This review will explore the current status of transrenal fixation of aortic stent-grafts, potential risks of stent struts relative to the renal ostium, alternative methods to preserve blood flow to the renal arteries, and future directions or developments in stent-graft design to prevent myointimal proliferation around the stent struts.

Endovascular aneurysm repair: treatment of choice for abdominal aortic aneurysm coincident with horseshoe kidney? three case reports and review of literature

There is still controversy as to which surgical method is the most suitable for repair of abdominal aortic aneurysm with concomitant horseshoe kidney (AAA-HSK). We report three cases of AAA-HSK treated with endovascular aneurysm repair. In one of these patients we sacrificed the accessory renal artery by applying coils before the operation. Renal infarction, hypertension, or elevated serum creatinine level was not observed in any of our patients. If the blood supply to the kidneys is taken into consideration, endovascular aneurysm repair is our preferred surgical method for repair of AAA-HSK when anatomic conditions are suitable for stent-graft application and kidney function is normal.