Iliac artery endofibrosis: diagnostic dilemna and treatment options.

Background: External iliac artery endofibrosis (EIAE) is an uncommon pathology, predominantly occurring in cyclists, caused by thickening of the external iliac artery intima. Symptoms are exercise-dependent and typically consist of pain, muscle cramps and loss of strength in the affected limb at (sub)maximal effort. As other musculo-skeletal as well as conditional problems might cause similar complaints diagnosis is not always easy or straightforward.

Case summary and discussion: We reviewed four cases of (semi-)professional cyclists referred to our department in 2021 because of suspicion of EIAE. In all symptoms only occurred at (sub)maximal effort. All had lowering of ABI on the affected side at a dynamic stress test on the bike. Imaging using CTA, MRA or dynamic angiogram was abnormal in all patients, showing signs suspicious for endofibrosis but of different kind and at different locations. Open surgical repair was performed in all cases by a procedure tailored to the type of lesion. Two patients were treated by a saphenous vein patch angioplasty, in one patient a shortening of the vessel and end-to-end anastomosis was performed and in the fourth patient a spiral saphenous vein graft bypass was placed. Postoperative course was uneventful and exercise was resumed after four weeks in all patients.

Conclusion: Correct diagnosis is essential in the treatment of EIAE. A complete and multidisciplinary pathway should be followed to distinguish vascular from non-vascular causes. Correct lesion localization is crucial and besides CTA or MRA, more sophisticated techniques such as dynamic angiography or intravascular ultrasound might be needed.