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Re: Use of Aortic Cuffs to Exclude Iliac Artery Aneurysms during AneuRx Stent-Graft Placement: Initial Experience
Letters to the Editor
Re: Use of Aortic Cuffs to Exclude Iliac Artery Aneurysms during AneuRx Stent-Graft Placement: Initial Experience From James E. Silberzweig, MD Department of Radiology St. Luke’s–Roosevelt Hospital Center 1000 Tenth Avenue New York, NY 10019
Editor: In the December 2001 issue of JVIR, Brown and colleagues (1) described their experience with the placement of aortic cuffs in dilated iliac arteries as part of endoluminal stent-graft aortoiliac aneurysm repair. The performance of “bell-bottoming” of the iliac limb of the stentgraft repair represented an alternative to internal iliac artery embolization and extension of the stent-graft to the external iliac artery. The authors made no specific distinction between the presence of a common iliac artery ectasia and an iliac artery aneurysm in their group of patients. The authors should have indicated the largest diameter of the common iliac artery as well as the diameter and length of the stent-graft landing zone. An adequate length of common iliac artery smaller than the diameter of the aortic cuff is required to prevent retraction of the stent-graft limb into the aneurysmal vessel. As in the proximal neck, the distal neck requires a stable arterial segment for effective attachment (2,3). The authors showed that placement of aortic cuffs in dilated iliac segments was feasible with no early type 1 endoleaks and suggested that long-term follow-up may prove that iliac ectasia may be treated as a suitable vascular segment for stent-graft attachment. Apposition of the stent-graft to an iliac aneurysm wall should not be considered aneurysm “exclusion,” as suggested in the title, because the iliac aneurysm proximal to the distal aneurysm neck continues to be exposed to direct arterial flow and pressure. These patients will require a lifetime of aggressive imaging follow-up to evaluate for progressive iliac artery dilation. References 1. Brown DB, Sanchez LA, Hovsepian DM, Rubin BG, Sicard GA, Picus D. Use of aortic cuffs to exclude iliac artery aneurysms during AneuRx stent-graft placement: initial experience. J Vasc Interv Radiol 2001; 12:1383–1387. 2. Schoder M, Zaunbauer L, Hölzenbein T, et al. Internal iliac artery embolization before endovascular repair of abdominal aortic aneurysms: frequency, efficacy, and clinical results. AJR Am J Roentgenol 2001; 177:599 – 605. 3. Soulen MC, Fairman RM, Baum RA. Embolization of the internal iliac artery: still more to learn. J Vasc Interv Radiol 2000; 11:543–545.
Drs. Brown et al respond:
We appreciate the interest Dr. Silberzweig has taken in our paper. As stated in our paper (1), aortic cuff sizes
546
were 3– 4 mm greater than those of the iliac arteries in which they were deployed. AneuRx cuffs are 3.75 cm in length and are available in diameters ranging in 2-mm increments from 18 mm to 28 mm. Therefore, a 24-mm iliac artery would be the largest vessel that could be treated with a cuff. Centering the cuff within the distal graft limb such that half the length extends into the native artery has been able to prevent type-1 endoleaks in our patients. This length (1.75 cm) is similar to the 2-cm requirement for the proximal aortic neck. Although our paper did review and refer to the Society for Vascular Surgery/International Society for Cardiovascular Surgery reporting standards for iliac artery ectasia/aneurysms (2), we would be happy to clarify differences in the anatomic definitions and the clinical management of iliac aneurysms. An iliac artery with a diameter of 18 mm or greater qualifies as an aneurysm. However, the smallest iliac aneurysms that undergo routine surgical repair are 30 mm in diameter. A longitudinal follow-up study of 179 patients with 323 iliac artery aneurysms supports this practice (3). In that trial, areas of ectasia and small aneurysms grew approximately 1 mm per year whereas iliac arteries 30 mm or larger grew at least 2.6 mm per year. It is reasonable to expect similar expansion rates in our patient group. Regarding Dr. Silberzweig’s final comment, our patients will require the same long-term follow-up that all patients with endografts will undergo. The Food and Drug Administration is encouraging, but not yet requiring, lifelong follow-up for all endograft patients (4). Many clinicians are following this initiative. As we stated in our paper, if the iliac vessels continue to expand, the internal iliac artery can be embolized and the graft extended into the external iliac artery. References 1. Brown DB, Sanchez LA, Hovsepian DM, Rubin BG, Sicard GA, Picus D. Use of aortic cuffs to exclude iliac artery aneurysms during AneuRx stent-graft placement: initial experience. J Vasc Interv Radiol 2001; 12:1383–1387. 2. Johnston KW, Rutherford RB, Tilson MD, Shah DM, Hollier L, Stanley JC. Suggested standards for reporting on arterial aneurysms. J Vasc Surg 1991; 13:444 – 450. 3. Santilli SM, Wernsing SE, Lee ES. Expansion rates and outcomes for iliac artery aneurysms. J Vasc Surg 2000; 31:114 – 121. 4. FDA Public Health Notification: Problems with Endovascular Grafts for the Treatment of Abdominal Aortic Aneurysm (AAA). Available at: http://www.fda.gov/cdrh/safety/ aaa.html. Accessed January 11, 2002.
Daniel B. Brown, MD Luis A. Sanchez, MD Daniel Picus, MD Mallinckrodt Institute of Radiology Washington University Medical Center St. Louis, Missouri
Re: Use of Aortic Cuffs to Exclude Iliac Artery Aneurysms during AneuRx Stent-Graft Placement: Initial Experience From James E. Silberzweig, MD Department of Radiology St. Luke’s–Roosevelt Hospital Center 1000 Tenth Avenue New York, NY 10019
Editor: In the December 2001 issue of JVIR, Brown and colleagues (1) described their experience with the placement of aortic cuffs in dilated iliac arteries as part of endoluminal stent-graft aortoiliac aneurysm repair. The performance of “bell-bottoming” of the iliac limb of the stentgraft repair represented an alternative to internal iliac artery embolization and extension of the stent-graft to the external iliac artery. The authors made no specific distinction between the presence of a common iliac artery ectasia and an iliac artery aneurysm in their group of patients. The authors should have indicated the largest diameter of the common iliac artery as well as the diameter and length of the stent-graft landing zone. An adequate length of common iliac artery smaller than the diameter of the aortic cuff is required to prevent retraction of the stent-graft limb into the aneurysmal vessel. As in the proximal neck, the distal neck requires a stable arterial segment for effective attachment (2,3). The authors showed that placement of aortic cuffs in dilated iliac segments was feasible with no early type 1 endoleaks and suggested that long-term follow-up may prove that iliac ectasia may be treated as a suitable vascular segment for stent-graft attachment. Apposition of the stent-graft to an iliac aneurysm wall should not be considered aneurysm “exclusion,” as suggested in the title, because the iliac aneurysm proximal to the distal aneurysm neck continues to be exposed to direct arterial flow and pressure. These patients will require a lifetime of aggressive imaging follow-up to evaluate for progressive iliac artery dilation. References 1. Brown DB, Sanchez LA, Hovsepian DM, Rubin BG, Sicard GA, Picus D. Use of aortic cuffs to exclude iliac artery aneurysms during AneuRx stent-graft placement: initial experience. J Vasc Interv Radiol 2001; 12:1383–1387. 2. Schoder M, Zaunbauer L, Hölzenbein T, et al. Internal iliac artery embolization before endovascular repair of abdominal aortic aneurysms: frequency, efficacy, and clinical results. AJR Am J Roentgenol 2001; 177:599 – 605. 3. Soulen MC, Fairman RM, Baum RA. Embolization of the internal iliac artery: still more to learn. J Vasc Interv Radiol 2000; 11:543–545.
Drs. Brown et al respond:
We appreciate the interest Dr. Silberzweig has taken in our paper. As stated in our paper (1), aortic cuff sizes
546
were 3– 4 mm greater than those of the iliac arteries in which they were deployed. AneuRx cuffs are 3.75 cm in length and are available in diameters ranging in 2-mm increments from 18 mm to 28 mm. Therefore, a 24-mm iliac artery would be the largest vessel that could be treated with a cuff. Centering the cuff within the distal graft limb such that half the length extends into the native artery has been able to prevent type-1 endoleaks in our patients. This length (1.75 cm) is similar to the 2-cm requirement for the proximal aortic neck. Although our paper did review and refer to the Society for Vascular Surgery/International Society for Cardiovascular Surgery reporting standards for iliac artery ectasia/aneurysms (2), we would be happy to clarify differences in the anatomic definitions and the clinical management of iliac aneurysms. An iliac artery with a diameter of 18 mm or greater qualifies as an aneurysm. However, the smallest iliac aneurysms that undergo routine surgical repair are 30 mm in diameter. A longitudinal follow-up study of 179 patients with 323 iliac artery aneurysms supports this practice (3). In that trial, areas of ectasia and small aneurysms grew approximately 1 mm per year whereas iliac arteries 30 mm or larger grew at least 2.6 mm per year. It is reasonable to expect similar expansion rates in our patient group. Regarding Dr. Silberzweig’s final comment, our patients will require the same long-term follow-up that all patients with endografts will undergo. The Food and Drug Administration is encouraging, but not yet requiring, lifelong follow-up for all endograft patients (4). Many clinicians are following this initiative. As we stated in our paper, if the iliac vessels continue to expand, the internal iliac artery can be embolized and the graft extended into the external iliac artery. References 1. Brown DB, Sanchez LA, Hovsepian DM, Rubin BG, Sicard GA, Picus D. Use of aortic cuffs to exclude iliac artery aneurysms during AneuRx stent-graft placement: initial experience. J Vasc Interv Radiol 2001; 12:1383–1387. 2. Johnston KW, Rutherford RB, Tilson MD, Shah DM, Hollier L, Stanley JC. Suggested standards for reporting on arterial aneurysms. J Vasc Surg 1991; 13:444 – 450. 3. Santilli SM, Wernsing SE, Lee ES. Expansion rates and outcomes for iliac artery aneurysms. J Vasc Surg 2000; 31:114 – 121. 4. FDA Public Health Notification: Problems with Endovascular Grafts for the Treatment of Abdominal Aortic Aneurysm (AAA). Available at: http://www.fda.gov/cdrh/safety/ aaa.html. Accessed January 11, 2002.
Daniel B. Brown, MD Luis A. Sanchez, MD Daniel Picus, MD Mallinckrodt Institute of Radiology Washington University Medical Center St. Louis, Missouri