Thoracic aortic aneurysm expansion due to late distal stent graft-induced new entry.

Abstract

This study analyzed the mechanism and risk factors of thoracic aortic aneurysm expansion due to late distal stent graft-induced new entry (dSINE). This late complication of thoracic endovascular aneurysm repair (TEVAR) for aortic dissection is under-recognized but potentially life-threatening. In 142 patients who underwent TEVAR with endovascular entry sealing for acute and chronic aortic type B dissection, using commercially available straight (nontapered) stent-grafts, we examined the oversizing rate, the aortic taper ratio, and the need for reintervention. Nine of 142 patients developed thoracic aortic aneurysm expansion due to dSINE after TEVAR. The median follow-up was 47.5 ± 37.4 months. There was a significant difference in the distal stent-aorta angle between the patients with and without dSINE (149.08 ± 15.09° vs. 166.72 ± 12.47°, P < 0.005). Patients with dSINE showed a significantly higher taper ratio of the true lumen of the aorta (40.9 ± 14.13% vs. 25.36 ± 20.2%, P < 0.05). There was also a significant difference in the oversizing of the stent-graft in the distal landing zone (95.88 ± 49.3% vs. 55.94 ± 36.23%, P < 0.01). All patients with dSINE underwent a secondary endograft procedure without any complications or deaths. In 7 cases we used a custom-made, highly tapered stent-graft. Lifelong follow-up of patients is mandatory after TEVAR. A stent-graft with a tapered design should be used in aortic dissection to avoid oversizing and devastating late complications.