The role of aortic neck dilation and elongation in the etiology of stent graft migration after endovascular abdominal aortic aneurysm repair with a passive fixation device

Device migration with aneurysm regression (the intra-aortic thrombus has been rendered transparent).

Measuring changes in the infrarenal aortic neck: a = b + c, where a is the infrarenal aortic neck length, b is the lowest renal to top of stent graft distance, and c is the proximal fixation length. Δa is aortic neck elongation, Δb is stent graft migration, and Δc is loss of proximal fixation length.

Life-table analysis of the probability of stent graft migration more than 5 mm. There were 223 patients at risk at 12 months, 137 patients at 24 months, 74 patients at 36 months, 30 patients at 48 months, 7 patients at 60 months, and 2 patients at 72 months.