Print this pageThe Effectiveness of the Lower Permeability Gore-Excluder Stentgraft in Preventing AAA Sac Enlargement: A Prospective Analysis
Melissa Shah, MD, Manish Mehta, MD, R Clement Darling III, Yaron Sternbach, MD, John B. Taggert, MD, Philip S.K. Paty, MD, Sean P. Roddy, MD, Paul B. Kreienberg, MD, Kathleen J. Ozsvath, MD, Benjamin B. Chang, MD and Dhiraj M. Shah, MD
Albany Medical College, Albany, NY
Purpose:
The findings of abdominal aortic aneurysm (AAA) sac expansion in the absence of endoleak from the Excluder phase II pivotal trial lead to the design of a lower permeability (LP) stentgraft which included the addition of a polytetrafluoroethylene layer to the original stentgraft. We prospectively evaluated volumetric and maximum AAA diameter changes in patients undergoing endovascular aneurysm repair (EVAR) with the LP Excluder and the ‘Original’ FDA approved devices.
Methods:
Since FDA approval of the LP Excluder stentgraft in July 2004, patients undergoing EVAR with this device at our institution had CT angiography preoperatively, and at every 6 month intervals thereafter. Detailed volumetric and maximum AAA diameter measurements were conducted with the use of calibrated Medical Metrx Solutions (MMS, Lebanon, NH) software. Aneurysm volume was measured from the infrarenal aortic neck to the distal common iliac arteries, and the maximum aneurysm diameter was measured perpendicular to the aneurysm centerline. Patients with the LP Excluder stentgraft (n=76) and at least a 12 month follow-up CT scan were compared to similar cohort of 100 consecutive patients with the original Excluder stentgraft treated from 2003-2004. Patients with any evidence of endoleak (Type I, II, or III) were excluded from this study.
Results: Table. Preoperative and 12 month postoperative CT scan findings of patients treated with the ‘Original’ vs. the lower permeability (LP) Excluder stentgraft.
| Original Excluder | LP Excluder | P-Value | |
| N | 100 | 76 | |
| Pre-op max AAA diameter (mean) | 53.4 mm | 54.1 mm | NS |
| Pre-op AAA Volume (mean/ ml) | 155.6 | 165.8 | NS |
| Post-op AAA Volume @ 12 mo (mean/ ml) | 160.3 | 149.5 | <0.05 |
| Change in AAA Volume @ 12 mo (mean/ ml) | +4.7 | -16.3 | <0.05 |
| AAA Volume Decrease >5% @ 12 mo | 6 (6%) | 39 (51%) | <0.05 |
| AAA Volume Increase >5% @ 12 mo | 12 (12%) | 2 (2.6%) | <0.05 |
| Max. AAA Diameter Decrease ≥5mm @ 12 mo | 8 (8%) | 18 (24%) | <0.05 |
| Max. AAA Diameter Increase ≥5mm @ 12 mo | 3 (3%) | 1 (1.3%) | NS |
Conclusions:
Midterm data suggests that the new lower permeability Excluder stentgraft appears to be significantly more effective in decreasing the AAA volume and maximum diameter when compared to the original device. Although these results are encouraging, further analysis with long-term follow-up is needed.