Length measurements of the aorta after endovascular abdominal aortic aneurysm repair.

Abstract

successful endovascular repair of abdominal aortic aneurysms (AAA) generally leads to a decrease in aneurysm size. Theoretically, this may lead to foreshortening of the excluded segment. If so, vertically rigid endografts may dislocate over time and cover renal or hypogastric arteries. to assess length changes of the infrarenal aorta after endovascular AAA exclusion. forty-four consecutive patients were scheduled for the EndoVascular Technologies endograft, a vertically non-rigid prosthesis which would potentially accommodate longitudinal changes. Twenty-four patients had completed at least 6 months of follow-up. In 18/24 patients a decrease in size was established by aneurysm volume measurements at 6 months' follow-up. Helical computer tomography (CT) angiograms were processed on a workstation. Aortic lengths were measured along the central lumen line from the lower renal artery orifice to the native aortic bifurcation. The computer tomography angiogram (CTA) reconstruction thickness of 2 mm yields at least a 4-mm error for each length measurement. in the shrinking aneurysm group, the median length change was 0 mm (range -9 mm to +4 mm) at 6 months' follow-up (n =18) and also 0 mm (range -7 mm to +4 mm) at 12 months' follow-up ( n =10). In 16/18 patients, length changes remained within the measurement error range of 4 mm. in this group of shrinking aneurysms after endovascular AAA repair, foreshortening of the excluded aortic segment appears not to be a clinically significant problem.