Evolution of Computed Tomography Imaging the First Year after Endovascular Sealing of Infrarenal Aortic Aneurysms Using the Nellix Device.

BACKGROUND: The Nellix endovascular aneurysm sealing (EVAS) system is an alternative endovascular treatment option for infrarenal aortic aneurysms (AAAs), with a unique appearance on computed tomography angiography (CTA). Normal evolution of post-EVAS CTA appearance follow-up is still largely unknown and important to timely detect eventual complications. The objective is to assess the normal appearance of CTA images 30 days and 1 year after EVAS in 50 consecutive patients. METHODS: Fifty patients treated with Nellix EVAS for an infrarenal AAA were included from 3 hospitals. Using dedicated software, a total of 150 CTA scans were analyzed by predetermined variables per anatomical segment. RESULTS: Thirty days post-EVAS, there was a slight, but not statistically significant, increase in AAA diameter that returned to the preoperative value after 1 year. A shift in total aortic volume distribution was observed without changing aortic diameter, including a trend toward a decreased thrombus volume (85.6 ± 49.1 mL and 78.8 ± 35.5 mL at 30 days and 1 year, respectively, P < 0.242) and a slight, but statistically significant, increase in polymer volume (68.2 ± 34.1 mL and 71.9 ± 35.2 mL at 30 days and 1 year, respectively, P < 0.001). The ß-angle (P = 0.06) and iliac artery angulation (P < 0.001) decreased after implant. The latter returned to its original state after 1 year, whereas the neck straightening remained. Over time, there was a significant decrease in radiodensity in the middle of the polymer-filled endobags with an increase at its edges (P < 0.05). Thrombus radiodensity significantly increased over the first year (P < 0.05). Diameters of the infrarenal neck and common iliac arteries remained unchanged, no endoleaks were observed, and the position of the device was stable. CONCLUSIONS: Change of CT appearance after EVAS is unique, and as such, the judgment of these images requires experience. The appearance of the endobags in respect to volume and radiodensity differ from classic EVAR. Normal changes over time are observed in aortoiliac angulation, volumes, and radiodensities.

In vivo geometry of the kissing stent and covered endovascular reconstruction of the aortic bifurcation configurations in aortoiliac occlusive disease.

Objectives Various configurations of kissing stent (KS) configurations exist and patency rates vary. In response the covered endovascular reconstruction of the aortic bifurcation configuration was designed to minimize mismatch and improve outcome. The aim of the current study is to compare geometrical mismatch of kissing stent with the covered endovascular reconstruction of the aortic bifurcation configuration in vivo. Methods Post-operative computed tomographic data and patient demographics from 11 covered endovascular reconstruction of the aortic bifurcation and 11 matched kissing stent patients were included. A free hand region of interest and ellipse fitting method were applied to determine mismatch areas and volumes. Conformation of the stents to the vessel wall was expressed using the D-ratio. Results Patients were mostly treated for Rutherford category 2 and 3 (64%) with a lesion classification of TASC C and D in 82%. Radial mismatch area and volume for the covered endovascular reconstruction of the aortic bifurcation group was significantly lower compared to the kissing stent configuration ( P < 0.05). The D-ratio did not significantly differ between groups. Measurements were performed with good intra-class correlation. There were no significant differences in the post-procedural aortoiliac anatomy. Conclusions The present study shows that radial mismatch exists in vivo and that large differences in mismatch exist, in favour of the covered endovascular reconstruction of the aortic bifurcation configuration. Future research should determine if the decreased radial mismatch results in improved local flow profiles and subsequent clinical outcome.

Common Iliac Artery Aneurysm Repair Using a Sac-Anchoring Endograft to Preserve the Internal Iliac Artery.

PURPOSE: To report the application of the Nellix endovascular aneurysm sealing system to successfully treat a unilateral common iliac aneurysm and preserve the internal iliac artery. CASE REPORT: An 85-year-old man presented with right-sided necrosis of the third and fourth toe. Computed tomography angiography (CTA) showed a right 40-mm popliteal aneurysm and a 38-mm left fusiform common iliac artery aneurysm. After endovascular exclusion of the popliteal aneurysm, the Nellix device was positioned to exclude the common iliac artery aneurysm while preserving the internal iliac artery. Postoperative CTA showed no endoleak and a patent internal iliac artery. At 1 year, duplex ultrasound documented a common iliac aneurysm diameter of 32 mm without complications. CONCLUSION: Endovascular sealing using the Nellix device can be applied to exclude selected common iliac artery aneurysms with an adequate length and a minimal distal neck, with preservation of the internal iliac artery. The endobag can be positioned such that the aneurysm is completely excluded while the orifice of the side branch is not endangered.