A Right Common Iliac Artery Pseudoaneurysm with an Iliac-Caval Arteriovenous Fistula: A Rare Complication of the Recovery Vena Cava Filter

Abstract

On September 2008 a 49-year-old man complaining ofback pain was admitted to our hospital. The patient wasnormotensive and suffered from an inoperable glioblas-toma of the right temporal lobe diagnosed by stereotaxicbiopsy on July 2007 and treated with radiochemotherapy.On June 2008 he complained of proximal deep veinthrombosis, and as anticoagulation was contraindicated, aninferior vena cava (IVC) filter was percutaneouslyimplanted at another hospital; no other clinical or radio-logical data on this procedure were available to us.At the time of the present hospitalization, a diagnosis ofspondylodiscitis of the lower dorsal spine complicated byperivertebral abscesses was made with a contrast-enhancedMRI of the spine and a contrast-enhanced whole-body CT.For both diagnostic imaging procedures contrast agentswere injected through a surgically isolated dorsal vein ofthe left foot, no other superficial veins being accessible.Abdominal CT scans identified a Recovery filter locatedin the lower tract of the IVC and a saccular aneurysmdeveloping along the lateral aspect of the aortic bifurcation;the aneurysmal neck was located at the origin of the rightcommon iliac artery. The filter penetrated the IVC wall andone of its legs was located within the aneurysm (Fig. 1A, B).The IVC was compressed and narrowed by the aneurysm;more proximally, at the level of the left renal vein, the longaxis and the short axis of the IVC measured 21 and 10 mm,respectively. Diagnosis of an iatrogenic pseudoaneurysm atthe origin of the right common iliac artery was made on thebasis of CT scans.AnabdominalaortographyconfirmedtheCTfindingsandalso demonstrated a high-flow arteriovenous fistula (Fig. 2).Endovascular repair with bilateral kissing aorto-iliac cov-eredstentswasattempted.Graftingoftherightcommoniliacartery required two stents, as the first one was inadvertentlyadvanced into the lumbar aorta; the left common iliac arterystent was deployed toforce the contralateral stentagainst theaneurysmal neck. Since endovascular stent-grafting failed,embolizationofthepseudoaneurysmwasperformedbothviathe right femoral artery and with a venous retrogradeapproach. Unfortunately the postprocedural abdominal aor-tography demonstrated persistent patency of both the pseu-doaneurysm and the arteriovenous fistula (Fig. 3).Spondylodiscitis was successfully treated with antibioticsand with percutaneous drainage. After the patient’s dis-charge serial sonographic investigations did not show anyincrease in size of the pseudoaneurysm. The patient died onApril 2009 from progression of the cerebral disease.Percutaneous implantation of an IVC filter is an effec-tive treatment for preventing pulmonary embolisms, butalthough the complication rate is low, long-term sideeffects remain an open question [1, 2]. Retrievable filtersare nowadays thoroughly preferred, as they can beremoved, even long after implantation, or can be alterna-tively left in situ as a permanent device [1, 3].Some types of filters anchor to the IVC wall withhooked legs. In up to 25% of cases these filters penetratethe vena cava wall and legs are found in the pericavalretroperitoneal tissue [1]; the small diameter of the IVCseems to facilitate filter penetration [1, 4]. This occurrenceis not considered clinically relevant in most cases [1, 5, 6],but it can theoretically preclude the retrieval of the filteritself. The legs of the filter can also penetrate contiguous