Complex right renal artery aneurysm treatment with a stent-graft after migration of an intra-aneurysmal bare stent

A 30-year-old man with a wide-necked 2 cm main right renal artery aneurysm presented for endovascular repair (Fig. 58.1). Coil embolization with a stent-assisted technique had failed at an outside hospital. The proximal edge of the bare stent had migrated into the aneurysmal sac and was abutting its wall, raising a risk of aneurysm rupture (Figs. 58.2 and 58.3). Therefore, exclusion of the aneurysm using a stent-graft through the cells of the migrated stent was planned. A guiding sheath was placed in the proximal aneurysm. A stiff guidewire was advanced distally through the stent cells, followed by a balloon-expandable stent-graft; unfortunately, the tip of its delivery system caught on the edge of the stent strut and could not be passed through the stent mesh, even after balloon dilation of the stent cells. After exchanging the stiff guidewire for a thinner flexible one, it was advanced through the wall cell because of a change in the angle between the stent and guidewire (Fig. 58.4). The stent-graft was successfully deployed. Although aneurysm exclusion was achieved, flow stagnation due to an ostial renal artery stenosis was seen, and hence, an additional stent-graft was placed. Final angiography confirmed patency of the vascular reconstruction and exclusion of the aneurysm (Figs. 58.5 and 58.6). At 8-month follow-up, computed tomography angiography confirmed patency of the renal stents and continued thrombosis of the aneurysm.