Objective: Endovascular abdominal aortic aneurysm repair (EVAR) with the original-permeability Excluder (W.L. Gore & Associates, Flagstaff, Ariz) has been associated with postoperative sac expansion in the absence of endoleak. In these cases, we have performed an endovascular revision, relining the original endograft with another Excluder, in an effort to arrest sac expansion by reducing permeability. We have studied these cases to determine the effect of relining on aneurysm expansion.
Methods: Patients who demonstrated sac expansion (>or=5 mm diameter, >or=5% three-dimensional volume) after EVAR with the original Excluder were evaluated. Between 1999 and 2004, the original-permeability endoprosthesis was used in 97 patients who underwent EVAR for asymptomatic abdominal aortic aneurysm (AAA). Sac expansion occurred in 24 patients, of which multiple imaging modalities showed 12 had expansion without demonstrable endoleak. Nine of the 12 have had endovascular relining, and five of these nine have >6 months follow-up to form the primary basis for this report.
Results: AAA size was stable or smaller in the first 6 months after the original EVAR for all patients. Once expansion began (typically in the time frame of 6 to 12 months), multimodality imaging showed no aneurysm spontaneously decreased in size without intervention, despite the absence of endoleak (n = 12). Expansion exceeded clinically significant thresholds at 30 months (mean) by diameter criteria and 22 months (mean) by three-dimensional volume criteria for the five patients with >6 months follow-up after relining. Endovascular relining was performed at a mean of 36 months, with a mean hospital stay of 1 day, and no morbidity or mortality. Over the entire duration of expansion (mean, 26 months), aneurysms expanded by 6.0 +/- 1 mm/year diameter and by 12% +/- 2%/year by three-dimensional volume. At a mean of 16 months follow-up after relining with another Excluder, the mean diameter decrease was 2.0 mm/year (P < .03) and the mean volume decrease was 2.6%/year (P < .01). After relining, all AAAs were smaller by diameter or volume, or both, exceeding thresholds defining shrinkage in two of the five with >6 months follow-up after relining. There was no rupture, migration, endoleak, conversion to open repair, or aneurysm-related death in any patient.
Conclusions: It appears from the initial follow-up that AAA expansion owing to permeability issues after EVAR with the original Excluder can be arrested by endovascular relining with a low-permeability Excluder endoprosthesis.