Stent Migration During Endovascular Repair of a Traumatic Pseudoaneurysm of the Innominate-Carotid Artery Bifurcation.

Stent Migration During Endovascular Repair of a Traumatic Pseudoaneurysm of the Innominate-Carotid Artery Bifurcation.
Introduction: Common carotid - inominate artery pseudoaneurysms
(CCIP) due to blunt trauma are rare. We report a case of CCIP treated by
endovascular means, complicated by stent migration.
Case Report: A 21 year old female was involved in a high speed MVA and sustained superficial liver and splenic lacerations and bilateral tibial fractures. As part of our trauma protocol, a thoracic CT scan with contrast was performed which demonstrated a tear along the CCI arteries and a 4.0 cm pseudoaneurysm amenable to endovascular repair. The patient had suffered a possible right hemispheric TIA and an "open" right carotid artery approach was performed in order to protect the right hemisphere by cross clamping the distal common carotid artery. Proximal common carotid retrograde access was obtained and a 8mm x 50mm Viabahn covered stent (W.L.Gore&Associates) was deployed across the CCIP. The stent "watermelon seeded" and immediately migrated into the thoracic aorta and lodged at the L1-2 interspace. A femoral artery cut down was performed in the hope of snaring and retrieving the stent. A pig tail catheter was placed above the stent and arteriography demonstrated it to be free floating over the SMA and renal artery orifices. The pig tail catheter was used to "coax" the stent distally where it lodged in the left common iliac proximal to the internal iliac artery without consequence. Attention was returned to CCIP and a larger Viabahn covered stent (9mm x 50mm) was deployed across the CCIP. Again the stent ejected to the L1-2 interspace and again it was coaxed distally with a pig tail catheter. A right femoral guide wire was then passed through the stent and it uneventfully lodged in the right common iliac artery. At this point the case was terminated.
Two days later, the patient successfully underwent percutaneous femoral artery access with placement of an Atrium 7mm x 60mm (Atrium) covered stent which excluded the CCIP. The patient was discharged on Clopidogrel and a CT scan two months later demonstrated exclusion of the CCIP
Conclusion: Endovascular repair of traumatic pseudoaneurysms is technically feasible and rapidly becoming the treatment of choice. Covered stents offer an acceptable option when urgent therapy is needed and when patients are deemed at high risk for an open repair. The complication encountered in this case emphasizes the watermelon seed effect of self-expanding stents, where the stent may be axially displaced, resulting in inaccurate, uncontrolled stent placement.