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For many patients with abdominal aortic aneurysm, unsuitable anatomy of the infrarenal aortic neck precludes endovascular aortic aneurysm repair or causes type I endoleak after the procedure. In an attempt to overcome these challenges, we retrospectively examined the usefulness of aortic banding as an adjunctive procedure to endovascular repair in 8 patients who had an abdominal aortic aneurysm with a complex infrarenal aortic neck. The procedures were performed with the patients under general anesthesia and involved making an 8-cm upper-midline laparotomy incision to expose the aneurysmal aorta. Three patients underwent aortic banding before endovascular repair; the other 5 underwent banding after the repair because of persistent type I endoleak. After banding, the abdominal aortic aneurysm was successfully excluded in all 8 patients. Long-term follow-up (mean, 38 ± 20 mo) revealed no type I endoleak and no procedure-related complications. In patients who have an abdominal aortic aneurysm with complex infrarenal neck anatomy or a refractory type I endoleak, performing aortic banding as an adjunctive procedure to endovascular aortic repair appears to be a safe strategy with good long-term results.
Endovascular abdominal aortic aneurysm repair (EVAR) is a rapidly expanding treatment method for abdominal aortic aneurysm (AAA).1 Unsuitable anatomy of the infrarenal aortic neck precludes EVAR in many patients,1–3 and this is the most common reason for EVAR ineligibility and subsequent surgical repair (in 106 of 165 patients in one study).4 In addition, investigators have reported that proximal attachment failure after EVAR frequently results in type IA endoleak. When left untreated, this sequela is associated with a high risk of AAA expansion and rupture.2–5 Various endovascular methods of reinforcing the neck from the inside have yielded largely unsatisfactory results.6,7 The failure of endovascular intervention often necessitates surgical repair and removal of the endograft, which increases the morbidity and mortality associated with EVAR.2,3,5,7
We examined the feasibility of reinforcing the “outside” of the aorta with an external aortic band.8,9 We report the cases of 5 men and 3 women who underwent EVAR, and in whom adjunctive external aortic banding was used to cinch and reinforce the proximal infrarenal aortic neck to treat or prevent type IA endoleak.
From February 2006 through August 2011, 8 consecutive patients underwent EVAR in which the adjunctive technique of external aortic banding was used to secure the proximal infrarenal neck and reinforce the aortic wall for the treatment or prevention of type I endoleak. All 8 patients were in American Society of Anesthesiologists Class IV. Table I shows their comorbid conditions. In 5 patients, aortic banding was performed after EVAR because of persistent type I endoleak. In 3 patients, aortic banding was performed before EVAR to create an appropriate infrarenal landing zone for the stent-graft.
Each patient was placed under general anesthesia. An 8-cm upper-midline laparotomy incision was made. The infrarenal retroperitoneum was opened through a 5-cm incision, and the aneurysmal aorta was exposed. Both renal arteries were identified and exposed, and the aorta was dissected circumferentially to free approximately 5 cm of its length from the surrounding tissues below the renal arteries. A graft-passer was then carefully placed around the aorta to avoid injuring the lumbar vessels, and a 12-mm Hemashield Gold™ graft (Boston Scientific Corporation; Natick, Mass) was pulled around the aortic aneurysmal neck, encircling it just below both renal arteries. The graft was measured to appropriate length, tightened around the aorta, and secured to the adventitia of the infrarenal aortic neck with 2-0 TiCron™ sutures (Covidien; Mansfield, Mass). A second 12-mm Hemashield graft was placed just distal to the first to further secure the aorta and to flatten the first graft. When this graft was in place, it was tightened and secured with 2-0 TiCron sutures, and the 2 grafts were then secured together with additional 2-0 TiCron and heavy #2 Ethibond Excel™ sutures (Ethicon, Inc., a Johnson & Johnson company; Somerville, NJ) (Fig. 1). The entire procedure was accomplished without cross-clamping the aorta or impairing flow to either renal artery, and blood loss was minimal. The retroperitoneum was closed after the Hemashield grafts were covered with adipose tissue. The omentum was placed between the duodenum and the aortic grafts, to prevent erosion of the graft into the intestine. After the abdominal cavity was irrigated, the abdominal incision was closed in standard fashion.
All 8 procedures were performed in a hybrid endovascular suite that was equipped with a flat-panel digital angiography camera and was compatible with surgical and general anesthesia requirements. Seven patients underwent percutaneous femoral artery access and repair. The other patient had severe peripheral vascular disease and required surgical femoral artery access and repair.
In the percutaneous approach, access to the left and right common femoral arteries was achieved by using a modified Seldinger technique with front-wall puncture. Bilateral 6F sheaths were inserted into the left and right common femoral arteries. Abdominal aortography was performed to evaluate proximal aortic neck anatomy and to obtain quantitative aortic measurements. One 10F ProStar® XL device (Abbott Vascular, part of Abbott Laboratories; Santa Clara, Calif) was used in the left and right femoral arteries for percutaneous femoral artery repair, with use of the pre-close technique that has been previously described.10,11 Heparin was administered intravenously to maintain an activated clotting time of 200 to 225 seconds. When aortic banding was performed simultaneously with the stent-graft procedure, banding was performed first, followed by deployment of the stent-graft.
A commercially available stent-graft was introduced into the ipsilateral femoral artery, either through an appropriately sized sheath (18F–24F) or directly. The stent-graft was then deployed in the infrarenal abdominal aorta. The contralateral limb of the stent-graft system was deployed into the contralateral femoral artery through an appropriately sized sheath.
Final angiographic examination of the abdominal aorta was performed to evaluate the results of EVAR. The sheaths were removed from the femoral arteries, and the Prostar XL sutures were delivered to the arteriotomy site via a sliding-knot technique to achieve hemostasis.10,11 Sterile dressings were applied to the femoral access sites.
The 8 patients in this study had multiple comorbidities, ranged in age from 72 to 86 years, and were considered to be at high surgical risk (Table I). All had substantial coronary artery disease, and 4 had ischemic cardiomyopathy, congestive heart failure, or both. Six patients had chronic renal insufficiency. The computed tomographic scans and abdominal angiograms revealed that 6 patients had a wide or short infrarenal neck with a reverse taper (Table II). The infrarenal necks were 0 to 12 mm long and 29 to 41 mm in diameter.
All the patients either had complex infrarenal aortic neck anatomy that was unsuitable for EVAR or had refractory type I endoleak (Table II). Three patients underwent a hybrid procedure of aortic banding and immediate EVAR to correct this problem (Table III); the other 5 underwent staged procedures.
Patients 2, 4, and 5 underwent aortic banding because of unfavorable aortic neck anatomy, and they underwent stent-graft placement during the same procedure (Fig. 2). Patients 1, 3, 6, 7, and 8 underwent aortic banding for persistent type I endoleak after multiple endovascular procedures had failed (Fig. 3). Patient 5 required a hybrid procedure to treat a descending thoracic aortic aneurysm with a thoracic stent-graft and left common iliac-to-celiac bypass. Three months later, he underwent the EVAR procedure without complications (Fig. 4).
After aortic banding, no procedural mortality and no significant sequelae occurred, except for a small type I endoleak that resolved spontaneously after 1 month of follow-up (Fig. 4). The duration of the banding and interventional procedure ranged from 135 to 320 min. The length of hospital stay ranged from 2 to 7 days.
The follow-up period was 2 to 60 months (mean, 38 ± 20 mo). No patient had procedural morbidity or developed complications during the follow-up period. However, one patient died of chronic lymphocytic leukemia (which he had before the procedure) after 36 months of follow-up (Table IV).
All 8 patients underwent aortic banding because their comorbid conditions made conventional AAA repair too risky. In our small series, both EVAR and aortic banding were accomplished without significant morbidity in high-surgical-risk patients who had unsuitable aneurysmal necks.
The standard treatment for AAA patients whose infrarenal aortic necks are too short or too severely calcified for EVAR is surgical repair. However, in patients with extensive comorbidity, the risk associated with surgical repair is very high.12–14 In this circumstance, the hybrid approach to AAA repair might prove to be optimal. To enable EVAR for AAA when the landing zone for stent deployment is unsuitable, the neck of the aneurysm must be altered to an appropriate diameter and length. The approach through a small laparotomy incision and the retroperitoneum yields adequate direct exposure of the infrarenal aorta. The dissection around the aorta is relatively simple; however, care must be taken to avoid tearing the lumbar artery or vein. After the dissection around the infrarenal abdominal aorta is accomplished, the 12-mm Hemashield graft can easily be placed around the aorta and secured at the desired diameter. The length of the graft can be calculated as L=2πR, where L represents the length of the graft and 2R equals the desired diameter of the aortic neck. This approximation gives the surgeon an estimated graft length that can be marked before the aorta is encircled. When the graft is secured and hemostasis is achieved, the surgical portion of the procedure is completed (typical operative time, 20–30 min).
Caution should be exercised in patients who have a substantial amount of thrombus in the infrarenal aorta, because banding could dislodge the thrombus into the renal arteries. There is also a risk that the infrarenal band will slip and obstruct the renal arteries.
The advantages of aortic banding are many. In patients with comorbidities, the length of the surgical procedure is important and proportional to postoperative morbidity and death.12–14 The aorta does not have to be clamped, which averts prolonged ischemia of the visceral organs. In surgical cases in which the AAA has no neck or the aneurysm extends to the renal arteries, the aorta is commonly clamped in the supraceliac region. This contributes to intestinal and renal ischemia. All of these maneuvers require much more operative time than aortic banding, and they contribute to morbidity and mortality.12,13 The external-banding approach circumvents aortic clamping and creates an appropriate landing zone for EVAR. Our gaining access to the infrarenal aorta through a small laparotomy incision enabled aortic banding to be accomplished in 20 to 30 minutes, which minimized the potential complications of prolonged surgical repair. Our long-term follow-up data suggest that this technique results in durable repairs in patients who have difficult AAA anatomy and who may not be surgical candidates because of their comorbidities.
Our typical approach in all patients with type I endoleak has been balloon angioplasty and placement of the aortic extension with or without suprarenal fixation to resolve the endoleak. In such instances, we have used the Palmaz® XL stent (Cordis Endovascular, a Johnson & Johnson company; Piscataway, NJ) in the aortic neck (Tables II and III). We performed aortic banding only when earlier measures failed (Figs. 2–4).
Aortic banding can be performed through the retroperitoneum without opening the abdominal cavity,9 thus simplifying this technique further. In the future, infrarenal aortic wrapping might be achievable with endoscopic techniques performed through the retroperitoneum.
This preliminary study of a small number of patients suggests that aortic banding is a safe and effective method of repairing AAAs that were previously amenable only to surgical resection. Our findings show that aortic banding benefited patients who had unfavorable infrarenal neck anatomy before EVAR, as well as patients who had a refractory type I endoleak after EVAR. The use of this technique can result in the durable treatment of hostile abdominal aneurysms in high-surgical-risk patients who would otherwise not be treated. Studies with larger numbers of patients and longer follow-up periods are needed to determine the safety and durability of this procedure in patients who have complex infrarenal neck anatomy and persistent type I endoleak after EVAR.
Stephen N. Palmer, PhD, ELS, contributed to the editing of the manuscript.
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