Morphological and functional modifications of the aneurysm-endograft complex following endoluminal treatment of abdominal aortic aneurysms

Abstract

Purpose.

The aim of the study was to evaluate quantitatively the main morphological changes of the abdominal aortic aneurysm (AAA)-endograft (EG) complex following endovascular repair of infrarenal AAA and to evaluate the functional consequences of these changes in terms of rate of complications (endoleaks and thrombosis). We also assessed whether these morphological and functional changes were related to the size of the AAA and to the type of EG used.

Materials and methods.

Eighty-five patients (M/F=82/3; mean age at time of operation 70.5±3.5 years, range 49.9–89.6 years) who underwent endovascular treatment of infrarenal AAA between April 1997 and October 2004 with a follow-up of at least 1 month were considered. All images of 408 preoperative and postoperative computed tomography (CT) studies were reviewed. Statistical analysis was performed with log-rank test on the 85 patients grouped according to AAA diameter <50 mm or ≤50 mm, and on 75 patients grouped according to EG device used (AneuRx, Talent or Excluder).

Results.

Morphological and dimensional changes involved the diameter (six cases) and length (14 cases) of AAA proximal neck, diameter (36 cases) and length (51 cases) of the aneurysm sac and shape of the stent-graft (47 cases). The prevalence of endoleaks was 37.6% whereas endoluminal thrombosis was observed in 27.1% of patients. AAA growth was significantly correlated (p=0.002) with the preprocedural diameter of the aneurysm sac whereas shrinkage was significantly correlated (p=0.0005) with the EG used.

Conclusions.

AAA growth was correlated with the diameter of the aneurysm sac while shrinkage was correlated with the EG used. During follow-up after endovascular repair, patients require careful evaluation of the morphological and dimensional features of the AAA and EG to promptly identify any changes that can anticipate major complications and even conversion to conventional surgery.