Management and therapeutic options for abdominal aortic aneurysm coexistent with horseshoe kidney

Horseshoe kidney (HSK), referring to the abnormal fusion of the lower renal poles, represents one of the most common renal anomalies. One of its most significant features is the anomalous vasculature, with a number of accessory renal arteries originating from the aorta, the mesenteric arteries, and even the iliac arteries supplying both the renal kidneys and the renal isthmus.

A literature review was performed to identify and to present the most recent data regarding classification and imaging evaluation of HSK concomitant with abdominal aortic aneurysm (AAA). Furthermore, an in-depth analysis of both open surgical and endovascular repair is made for management of this rare medical condition.

The anomalous renal vasculature of HSK has led to the introduction of a number of classification systems, with Eisendrath's being currently the most commonly used. The concomitant presence of HSK in patients suffering from AAA plays a major role in preoperative planning, with a number of factors taken into consideration in deciding on either an open repair or an endovascular approach. Open repair requires careful decision-making between a transperitoneal and a left retroperitoneal approach to reach the aneurysm sac. In addition, technical points include the decision to divide the renal isthmus or not and the necessity of salvage or reimplantation of anomalous renal vessels. On the other hand, an endovascular approach requires careful preoperative imaging and evaluation of both the renal function and vasculature to decide on catheterization and salvage of accessory renal arteries or their exclusion.

The concomitant presence of AAA and HSK poses a challenge for the modern vascular surgeon, who must possess all required technical skills-both endovascular and open repair-to deal accordingly with this rarely encountered medical condition. Preoperative determination of the perfusion pattern is necessary for the treatment strategy.