Aneurysm expansion after stent-graft placement in the absence of endoleak

Sixty-three patients with thoracic or abdominal aortic aneurysms were treated with endovascular stent-grafts. No endoleak was identified at any interval of follow-up in 58 patients. In four of them (7%), the aneurysms expanded by 10 mm or more during follow-up and additional interventions were required. Aneurysm expansion was caused by inappropriate sealing at the aneurysmal necks in two patients and transgraft seroma in the other two. Although some aneurysm expansion could be avoided by proper patient selection and accurate placement of stent-grafts, it seems difficult to predict aneurysm expansion in most cases.