Peripheral Vascular Surgery Society
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Peripheral Vascular Surgery Society |
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#23 ACCURACY OF PROXIMAL ATTACHMENT DEPLOYMENT IN ENDOVASCULAR AORTIC GRAFTING FOR ANEURYSMS
David H. Deaton, MD, Karl Chiang, MD, William H. Bogey, MD, Denise Brigham, BSN, and C. Steven Powell, MD
East Carolina University Greenville, NC
Introduction: Endovascular graft fixation methods employ either: a) apposition and radial force distributed over a longitudinal section of aorta, or b) discrete transaortic fixation at a specific locus. Rapid diminution of aortic tensile strength and elastin content distal to the renal arteries are implicated in the susceptibility of the infrarenal aorta to aneurysmal degeneration. Long-term success of endovascular grafting depends on the attachment competence in perirenal aorta least susceptible to future aneurysmal dilation. Late graft migration and graft incompetence can occur if the aorta dilates beyond the diameter of the endovascular graft. This study determined the accuracy of a discrete transaortic proximal attachment system.
Methods: Endovascular aortoiliac (bifurcated n=18, straight aortoiliac n=2) (Endovascular Graft System [EGS], Guidant/EVT, Menlo Park, CA) grafts were placed in 20 patients over an 8 month period under the protocol of an FDA Phase II clinical trial. Radiographs from eighteen of these cases were adequate to determine the accuracy to which the proximal attachment system was implanted relative to a desired radiopaque marker positioned at the inferior margin of the lowest renal artery. Measurements were taken at the lateral borders of the aorta and recorded as positive for attachment above the desired location and negative for the converse and recorded separately as an average to account for angulation. Abdominal radiographs and CT scans at three and six months were reviewed for evidence of neck dilation or graft migration.
Results: The right lateral attachment system averaged - 1 mm (range: 3 to-6) relative to the desired location with 83% within 3 mm and 72% within 2 mm. The left lateral attachment system averaged -1 mm (range: 2 to -5) relative to the desired location with 83% within 3 mm and 78% within 2 mm. The averaged relative location was also -1 mm with 89% within 3 mm and 78% within 2 mm. There was one case (6 mm) where proximal deployment was more than 5 mm from the target. There is no evidence of proximal leak, late migration or neck dilation at 14-20 months follow-up.
Conclusions: The proximal attachment system can be positioned and implanted with a high degree of accuracy using a device with discrete transmural attachment. Long-term studies will be required to determine the effects of various attachment methodologies on the juxtarenal aorta and the consequences of neck dilation at the site of attachment.
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Last updated January 10, 1999