Exclusion of an Infrarenal AAA with Coincident Horseshoe Kidney and Renovascular Anomalies is Feasible Using a Standard Stent-graft

Single Branch Endovascular Aortic Repair Procedure for an Abdominal Aortic Aneurysm in a Patient With Horseshoe Kidney: A Case Report

Introduction

Horseshoe kidney (HK) is an anatomical variant characterised by abnormalities in the position, rotation, and vascular supply of the kidney, with functioning renal masses on both sides of the vertebral column fused together at the isthmus. Due to the altered pattern of kidney vasculature, endovascular aortic repair for aortic abdominal aneurysm (AAA) in the presence of HK requires vascular anatomy specific planning.

Report

A 68 year old male, with multiple comorbidities, presented with an asymptomatic AAA and HK. The kidney vasculature was characterised by the presence of three arteries: two arising laterally at the same level and a third polar artery arising from below. The polar artery was 6 mm in diameter and larger than the other two; therefore, in order to preserve this artery, a custom-made device with a single side branch was implanted below the main renal arteries. A balloon expandable covered stent was used to complete the side branch into the polar renal artery. The follow-up computed tomography angiography revealed a successful outcome, with total aneurysm exclusion, branched graft patency, no endoleak, and unchanged renal function.

Discussion

This case report shows a possible surgical solution for a case of HK with AAA and the importance of accurate endovascular planning. Large polar arteries, if present, need to be preserved, and custom-made devices in the modern endovascular era permit that. This approach could represent the best option for complicated patients.

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.

Fenestrated endovascular aneurysm repair with concomitant horseshoe kidney

Horseshoe kidney (HSK) is a rare anatomic anomaly that poses surgical challenges in the setting of abdominal aortic aneurysm repair. An endovascular approach is safer for patients yet carries technical challenge because of variable renal vasculature. We present the case of a patient with an infrarenal abdominal aortic aneurysm and concomitant HSK who underwent successful repair with a custom fenestrated endograft with preservation of a midaortic renal artery. Complex endovascular aneurysm repair options for HSK include chimneys and fenestrated stent grafts. We suggest that the availability of custom fenestrated grafts and ongoing skill enhancement among vascular surgeons may make this approach more favorable.

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.

Management of Aortoiliac Aneurysms with Atypical Renal Artery Anatomy

BACKGROUND

Renal artery anomalies occur at a rate of 1-2% and present a challenge to vascular surgeons performing aortic surgery. We describe adjuncts used to manage such anatomic variants.

METHODS

A single surgeon registry of all abdominal aortic aneurysms repaired in an academic center was retrospectively reviewed. Patients with prior renal transplants, congenital pelvic kidneys, or horseshoe kidneys were included. Open repair was reserved for patients with no endovascular or hybrid repair options.

RESULTS

Over an 8-year period, 18 patients were identified (renal transplant n = 9, horseshoe kidney n = 3, congenital pelvic kidney n = 6). All transplant patients were treated with endovascular repair. Four required cross-femoral bypasses, 1 for retrograde allograft perfusion after aorto-uni-iliac (AUI) procedure to the contralateral external iliac artery and 3 for contralateral limb perfusion after endograft extension into iliac artery ipsilateral to allograft. Three transplant patients required carotid access due to severe iliofemoral occlusive disease or allograft origin off the internal iliac artery. Two horseshoe kidney patients underwent open repair with direct reimplantation of accessory renal arteries, whereas 1 underwent endovascular repair with exclusion of an isthmus branch. Of the congenital single/pelvic kidney cohort, 2 underwent open repair with renal reimplantation, 2 underwent endovascular aneurysm repair, 1 was treated with AUI and cross-femoral bypass, and one was treated with a staged iliorenal bypass and subsequent fenestrated endovascular repair. Intravascular ultrasound was used to minimize contrast use in patients with chronic renal insufficiency (Cr > 1.5 mg/dL, n = 6). Over a mean follow-up of 31 months (range, 1-110), there were no aortic deaths or reintervention, no decline in renal function (measured by serum creatinine and glomerular filtration rate), and 100% patency of the preserved renal arteries.

CONCLUSIONS

Atypical renal anatomy should not preclude repair of aortic aneurysms. Repair of such aneurysms is safe and achieves good long-term outcomes with the use of the described techniques.

A Novel Chimney Approach for Management of Horseshoe Kidney During EVAR

INTRODUCTION

Abdominal aortic aneurysms (AAAs) with coexisting horseshoe kidney (HSK) can be difficult to repair, with variable blood supply from the aorta and iliac/mesenteric vessels. Endovascular aneurysm repair (EVAR) has become a popular, less invasive approach to aneurysm care, and a chimney approach to EVAR (ChEVAR) has expanded its use to more complex anatomy. It is mandatory to maintain adequate perfusion to the HSK and visceral branches as part of the treatment of an AAA.

REPORT

A 61-year-old male with an HSK was incidentally found to have an infrarenal AAA that measured 6 cm on a non-contrast computed tomography (CT) scan performed originally for a urologic complaint. A diagnostic angiogram was performed to define arterial anatomy and he was found to have a large inferior mesenteric artery (IMA) arising 1 cm above the level of the aneurysm. ChEVAR was performed to preserve the IMA and flow to the HSK with a completion angiogram revealing patent renal arteries, IMA, and no evidence of an endoleak. Follow-up CT imaging demonstrated a Type II endoleak that resolved upon partial nephrectomy for a right-sided transitional cell carcinoma with resection of the arterial blood supply feeding the Type II endoleak.

DISCUSSION

IMA preservation via ChEVAR is technically feasible and was crucial to preserve blood supply via the IMA to the HSK. Partial nephrectomy treated the transitional cell carcinoma and resolved the Type II endoleak requiring no additional endovascular intervention. A unique treatment course demonstrated the benefits of less invasive interventions when repairing AAA with an HSK.