Ilio-Iliac Arteriovenous Fistulae—An Unusual Diagnosis with an Even More Unusual Clinical Presentation

Major pelvic ilio-iliac arteriovenous fistula (AVF) is an exceedingly rare diagnosis with only a few described cases in the literature, most of them related to congenital defects or trauma. In this case report, we aim to present a case of an ilio-iliac AVF with an atypical clinical presentation.Relevant medical data were collected from hospital database.The patient is a 77-year-old woman, with a relevant medical history of a temporally remote hysterectomy. She developed an exuberant unilateral right leg edema and was diagnosed with a femoro-iliac deep vein thrombosis (DVT) and started on anticoagulation and daily use of elastic compression stockings. No improvement in leg edema was evident, and she reported painful complaints refractory to medication. She also progressively developed right foot numbness and foot drop. A computed tomography angiography (CTA) was performed to exclude any compressive or paraneoplastic syndrome, with no remarkable findings other than common iliac vein (CIV) occlusion. As the patient's symptoms continued to worsen, a new CTA was performed 5 months later, which revealed an ilio-iliac AVF that was confirmed by angiography. After 2 ineffective attempts to embolize AVF afferents, we chose to completely embolize the arterial component of the AVF with Helix EV3 coils and Onyx glue (Covidien, Irvine, CA, USA). CIV recanalization and deployment of a Venovo stent (Bard Inc, Tempe, AZ, USA) was also performed. The final angiograms showed exclusion of the AVF and rapid venous flow through the stent. There was progressive improvement of edema and pain but little improvement of foot drop.AVF etiology and mechanism of neurologic deficits are controversial, with multiple possible explanations. Endovascular treatment modalities are promising a safer and more efficient approach when compared with open surgery. Our experience in this case was encouraging, but long-term results are currently lacking.