Embolotherapy of persistent endoleaks after endovascular repair of abdominal aortic aneurysm with the ancure-endovascular technologies endograft system

Long-Term Outcomes Following Transarterial Embolisation of Proximal Type I Endoleaks Post-EVAR

PURPOSE

To describe the long-term outcomes following transarterial embolisation for type Ia endoleaks (ELIa) in patients who failed or were unsuitable for standard endovascular/surgical options.

MATERIALS AND METHODS

A retrospective single-centre observational study was performed between October 2010 and April 2018. Technical success rates and long-term outcomes were evaluated. A sub-analysis was performed comparing outcomes of covered aortic endografts and Nellix endovascular aneurysm sealing systems.

RESULTS

A total of 34 transcatheter embolisations were performed for ELIa in 27 patients (13 endografts and 14 patients with Nellix systems). A combination of Onyx and coils was used most frequently (18/34), followed by Onyx alone (14/34) and coils alone (2/34). Technical success was achieved in 33/34 (97%) procedures . Seven early complications occurred with no immediate mortality, 5 of which involved migration/reflux of embolic into the endograft-all successfully managed via endovascular approach. Following the surveillance period (mean 25 months), 13/26 (50%) of patients were free from recurrent endoleak. Sac expansion occurred in 42% (11/26). 21/26 patients died; 6 due to aneurysm sac rupture, 10 due to unrelated causes, and 5 had no cause of death available. No significant difference in survival was found between patients with an endograft or Nellix graft-Chi-squared value - 0.011 (p < 0.05 = 3.84).

CONCLUSIONS

Transcatheter embolisation for type Ia endoleaks is a safe and effective option in a select patient cohort-where traditional endovascular and surgical options are unsuitable or have failed. The procedure may prevent recurrence in some whilst delaying rupture and death in others.

Prophylactic Aneurysm Embolization during EVAR Is Safe, Improves Sac Regression and Decreases the Incidence of Type II Endoleak

BACKGROUND

Clinically significant endoleaks remain costly, time-consuming, morbid and even mortal following endovascular aneurysm repair (EVAR). Perigraft arterial sac embolization (PASE) has been utilized to treat type II endoleaks (T2EL) diagnosed at the time of EVAR or after repair. Our objective was to analyze the safety and efficacy of prophylactic PASE on the incidence of T2EL and aneurysm sac regression in patients undergoing EVAR.

METHODS

We performed a retrospective review of prospectively maintained databases from the University of California San Diego and the San Diego Veterans Affairs hospitals between 2015 and 2019. Prophylactic PASE (pPASE) was performed at the time of EVAR with thrombin, contrast and gelfoam liquid embolic aneurysm treatment as previously described. We evaluated technical success, freedom from T2EL, freedom from reintervention, from sac expansion, from type I/III EL, from all-cause mortality (ACM), from aneurysm-related mortality and from non-target embolization (NTE).

RESULTS

A total of 44 patients were included in the study. Technical success was 100% and no NTE was observed. The average duration of follow-up was 14 ± 11months. In those treated and followed by CT scan, 100% of patients' aneurysms halted their growth following PASE, while 65.9% demonstrated sac regression. Mean aneurysm sac diameter decreased by 9 mm (95% CI 7-12). At 3 years, freedom from T2EL was 87.1%. Presence of T2EL did not result in aneurysm expansion during the follow-up period and thus did not require reintervention in any of these patients. Freedom from re-intervention was 83.2% for Type Ib EL and limb occlusion and all procedures were determined to be successful at the time of completion. No aneurysm-related deaths occurred during the follow-up.

CONCLUSIONS

PASE proves to be an effective tool in sac management for prophylaxis of endoleak and maximizing sac regression in EVAR. It is safe, effective and durable when employed in this manner in the short and medium-term and was associated with low rates of T2ELs and reinterventions and a 100% freedom from sac expansion. Further analysis is required to evaluate the long-term outcomes of this adjunctive procedure in EVAR.

Secondary Endoleak Management Following TEVAR and EVAR

Endovascular abdominal and thoracic aortic aneurysm repair and are widely used to treat increasingly complex aneurysms. Secondary endoleaks, defined as those detected more than 30 days after the procedure and after previous negative imaging, remain a challenge for aortic specialists, conferring a need for long-term surveillance and reintervention. Endoleaks are classified on the basis of their anatomic site and aetiology. Type 1 and type 2 endoleaks (EL1 and EL2) are the most common endoleaks necessitating intervention. The management of these requires an understanding of their mechanics, and the risk of sac enlargement and rupture due to increased sac pressure. Endovascular techniques are the main treatment approach to manage secondary endoleaks. However, surgery should be considered where endovascular treatments fail to arrest aneurysm growth. This chapter reviews the aetiology, significance, management strategy and techniques for different endoleak types.

Midterm evaluation of perigraft arterial sac embolization in endovascular aneurysm repair

OBJECTIVE

Management of clinically significant endoleaks (ELs) remains costly, time-consuming, and morbid. Unresolved ELs can result in rupture and mortality after endovascular aneurysm repair (EVAR). Perigraft arterial sac embolization (PASE) has been used to treat ELs diagnosed at the time of EVAR or during surveillance.

METHODS

A retrospective review of prospectively maintained databases was conducted. The databases were compiled from two institutions between 2006 and 2016. PASE was performed for type I, type II, or type III EL with a thrombin, contrast medium, and Gelfoam (Pfizer, New York, NY) slurry prepared as previously described. PASE was administered either at the time of EVAR (primary) or during surveillance (secondary). Safety end points included nontarget embolization, defined as neurologic or enteric clinical sequelae from lumbar artery or visceral artery embolization, allergic reaction, peripheral embolization, or rupture. Efficacy end points included successful resolution of EL and cessation of aneurysm sac growth on computed tomography (CT) scans with contrast enhancement.

RESULTS

A total of 66 patients included in the study were treated with PASE. Primary PASE was performed in 38 patients (58%) and secondary in 28 (42%). Within the total cohort, the average clinical and CT scan follow-up was 1.7 years (0.1-11.6 years). Four patients required open repair for residual high-pressure ELs (one type IIIB and three type I; 6%). Of the 95% of patients who did not require open conversion, aneurysm growth did not occur during the follow-up period. In the overall cohort, PASE was successful in 88% of type I EL and 73% of patients with type II EL. There was no evidence of recanalization after thrombosis of culprit vessel for EL. No patients suffered nontarget embolization, spinal ischemia, allergic reaction, post-EVAR rupture, or colonic ischemia.

CONCLUSIONS

Primary and secondary PASE proved to be a safe, effective, and durable tool in sac management in conjunction with EVAR. Treating ELs during or after EVAR with PASE has minimized the incidence of EL on CT scan and halted aneurysm growth in our cohort. Further studies are needed to confirm the long-term durability of PASE in reducing secondary interventions after EVAR.

The Roadside Technique for Type II Endoleak Embolization 4 Years after Endovascular Aortic Aneurysm Repair

Endoleaks are the most common cause of reintervention after endovascular aortic aneurysm repair (EVAR). Type II endoleaks have been implicated as a risk factor for expansion and rupture. Several techniques have been described to manage type II endoleaks, being transarterial catheterization the most commonly used. In some cases this technique can be difficult or impossible to achieve. We report the use of a technique that offers a direct access to the aneurysm sac and the possibility of catheterization of the involved vessels or the embolization of the communication between them, even 4 years after EVAR.

Systematic Review and Meta-analysis of 12 Years of Endovascular Abdominal Aortic Aneurysm Repair

BACKGROUND

Endovascular repair (ER) of abdominal aortic aneurysm (AAA) is a new technique, and reported rates of endoleak, conversion to open repair, rupture and mortality vary widely. The aim of this study was to estimate these rates from the published data, and examine how this has changed as more patients have undergone ER.

METHODS

A systematic review and meta-analysis of publications identified through searches of the electronic databases EMBASE and Medline. All publications quoting endoleak, conversion to open repair, rupture and mortality rates for a series of patients undergoing ER were included.

RESULTS

163 studies pertaining to 28,862 patients undergoing ER were identified as relevant for the review and meta-analysis. The pooled estimate for operative mortality was 3.3% (95% confidence interval 2.9 to 3.6%). The pooled estimate for type 1 endoleaks was 10.5% (95% confidence interval 9.0 to 12.1%), with an annual rate of 8.4% (95% confidence interval 5.7% to 12.2%). The pooled estimate of type 2,3 and 4 endoleaks was 13.7% (95% confidence interval 12.3 to 15.3%), with an annual rate of 10.2% (95% confidence interval 7.4% to 14.1%). The pooled estimate for primary conversion to open repair was 3.8% (95% confidence interval 3.2 to 4.4%), and for secondary conversion to open repair 3.4% (95% confidence interval 2.8 to 4.2%). The pooled estimate for post-operative rupture was 1.3% (95% confidence interval 1.1 to 1.7%), with an annual rupture rate of 0.6% (95% confidence interval 0.5% to 0.8%). Multivariate meta-regression analysis showed that rates of operative mortality, post-operative rupture and total number of endoleaks all fell significantly (p<0.05) over time.

CONCLUSIONS

This study demonstrates a low mortality and a gradual reduction in vascular morbidity and mortality associated with endovascular repair since it was first introduced.

Endoleakage after endovascular treatment of abdominal aortic aneurysms: diagnosis, significance and treatment

Endoleak, also called leakage, leak and Perigraft leak, is a major complication and its persistence represents a failure of endovascular aortic aneurysm repair. Its detection and treatment is therefore of primary importance, since endoleak can be associated with pressurization (increase in pressure) of the sac, resulting in expansion and rupture of the aneurysm. The aim of this paper is to discuss the definition, significance, diagnosis and different options to treat endoleak.

Embolization of Type 2 Endoleaks after Endovascular Repair of Abdominal Aortic Aneurysms with Use of Cyanoacrylate with or without Coils

Translumbar embolization was used to treat 11 type 2 endoleaks in nine patients with the liquid embolic agent n-butyl cyanoacrylate (NBCA). Nine of the embolizations were performed with a combination of stainless-steel coils and NBCAJ and the other two were performed with NBCA alone. There was complete occlusion on initial computed tomographic (CT) angiography in six of nine patients (66%), including the two cases treated with NBCA alone. Persistent endoleak on initial CT angiography occurred in three of nine patients (33%). Two of these patients underwent successful repeated embolization with NBCA. Aneurysm size remained unchanged in four patients (44%), decreased in four patients (44%), and increased in one patient (11%). No complications occurred. Initial results with the use of NBCA for endoleak embolization are encouraging.

Endoleak: Treatment Options

Endoleak, also called leakage, leak, and Perigraft leak, is a major complication and its persistence represents a failure of endovascular aortic aneurysm repair (EVAR). Its detection and treatment is therefore of primary importance since endoleak is associated with pressurization (increases pressure) of the sac, resulting in expansion and rupture of the aneurysm. The aim of this article was to discuss the different options to treat endoleak.

What is the significance of endoleaks and endotension

Endovascular repair has been used over a decade as a treatment of abdominal aortic aneurysm, and has become a widely accepted treatment method with a low rate of perioperative complications. Endoleak, perigraft blood flow outside endograft but within aneurysmsac, has been intensively studied during the last 10 years of endovascular aneurysm repair (EVR). The natural history of aneurysms with endoleak and the true clinical significance of various types of endoleaks remains unclear. Type I/III endoleak has been found to be associated with aneurysm rupture, while the risk of rupture of aneurysms with type II endoleak and endotension appears very small. In endotension, the aneurysm sac remains pressurized, even if there is no evidence of an endoleak. Currently,it is accepted that type I/III endoleaks should be corrected, preferably by endovascular means, due to the risk of rupture. If endovascular repair is not possible, then open conversion should be considered. The risk of conversion should be weighed against the risk of aneurysm rupture. Treatment of type II endoleaks and endotension is more controversial. In those with aneurysm enlargement,secondary interventions are often performed.

Endovascular repair of an aortopulmonary artery fistula with use of controlled-release coils

Aortopulmonary artery fistula is traditionally treated surgically. The present case report describes endovascular repair of an aortopulmonary artery fistula in a patient in whom two thoracotomies had been performed. The fistula occurred at the site of a pseudoaneurysm from the proximal anastomosis of a graft placed to treat a type B aortic dissection. Two controlled-release endovascular coils were positioned across the fistula, resulting in immediate closure. The fistula remains closed with resolution of the pseudoaneurysm after more than 3 years of follow-up.

Inferior vena cava traversal for translumbar endoleak embolization after endovascular abdominal aortic aneurysm repair

When embolization of a collateral (type II) endoleak after endovascular repair of an abdominal aortic aneurysm is indicated, endoleak embolization with a translumbar approach is often the procedure of choice. Because of the position of the endoleak, it is sometimes necessary to use a right-sided translumbar approach and traverse the inferior vena cava when accessing the endoleak. Twelve type II endoleaks in nine patients were treated with transcaval translumbar embolization during a 34-month period. No clinically significant hemorrhage occurred. Embolizing type II endoleaks with a right translumbar approach is feasible. Long-term follow-up with more patients is necessary to fully evaluate the durability of this procedure.

Outcomes of secondary interventions after abdominal aortic aneurysm endovascular repair

PURPOSE

We assessed the distribution of secondary interventions after aortic stent grafting (EVAR) performed to treat infrarenal abdominal aortic aneurysm (AAA), and evaluated clinical success and survival in patients who underwent a secondary procedure (group 2) compared with patients who did not undergo a secondary procedure (group 1).

METHODS

Two hundred fifty patients (mean age, 71.3 years) with asymptomatic AAAs (mean aneurysm diameter, 54.5 mm) underwent treatment with commercially available stent grafts. Mean follow-up was 28 months (median, 25 months). Secondary procedures were defined as any additional procedures performed after initial graft placement to treat endoleak, migration, kinking, stenosis, or occlusion. Overall clinical success was defined according to reporting standards of the Society for Vascular Surgery/American Association for Vascular Surgery.

RESULTS

Sixty-eight patients (27%) required 112 secondary procedures, with a mean time from initial graft placement of 18.2 months. Patients who received grafts since removed from the market required more secondary procedures (59%, procedure:patient ratio) compared with patients who received devices still on the market (21%; P =.001). Thirty-six patients (53%) required a single secondary procedure, 24 patients (35%) required two procedures, 5 patients (10%) required three procedures, 2 patients (3%) required four procedures, and 1 patient required five secondary procedures. Ninety-eight procedures (87%) were performed with endovascular methods, including placement of 42 additional covered stent grafts (36 iliac, 6 aortic), with a success rate of 85%; 35 embolization procedures (21 lumbar, 9 internal iliac artery, 5 mesenteric), with only 23 (65%) successful; 14 angioplasty procedures, with 85% successful; 4 thrombolysis procedures, 2 of them successful (50%); and 3 successfully placed new endografts within a previous endovascular graft. Surgical secondary operations included nine femorofemoral bypass procedures and three femoral thromboendarterectomies, all of which remain patent; one cerclage of an external iliac limb; and one laparoscopic repair of a type II endoleak, which was successful. Overall clinical success rate for EVAR was 84% (211 of 250) in this series. Clinical success rate in groups 1 and 2 was 91% (166 of 182) versus 66% (45 of 68; P =.001) if all endoleaks on the most recent computed tomography scans are taken into account, and 94% (171 of 182) versus 76% (52 of 68; P =.001) if type II endoleak without aneurysm growth is not considered failure. The survival rate and rupture-free survival in groups 1 and 2 were, respectively, 97.7% +/- 1.0% and 98.5% +/- 1.4% at 1 month, 95.9% +/- 1.5% and 96.9% +/- 2.1% at 6 months, 94.4% +/- 2.0% and 93.2% +/- 3.4% at 1 year, and 80.8% +/- 5.2% and 88.5% +/- 5.0% at 3 years (P =.273, log-rank test).

CONCLUSION

With close follow-up and a significant number of secondary operations, this 8-year experience has not included any aneurysm ruptures to date. Secondary operations did not lead to increased mortality, but were associated with more surgical conversions and with a higher clinical failure rate.

Initial successful management of type I endoleak after endovascular aortic aneurysm repair with n-butyl cyanoacrylate adhesive

OBJECTIVE

Transcatheter embolization with coils and other agents has been described as a treatment method for type II endoleak after endovascular aortic aneurysm repair (EVAR). Type I endoleak has not been treated commonly with such therapies, although most investigators believe they warrant definitive intervention. The liquid adhesive n-butyl 2-cyanoacrylate (n-BCA) is often used to treat congenital arteriovenous malformations. The objective of this study is to report our initial experience in treating type I endoleak with n-BCA and with a variety of other interventions.

METHODS

A retrospective review was performed of 270 patients who underwent EVAR at our institution between January 1994 and December 2002. Of these, 24 patients had type I endoleak (8.9%), diagnosed either intraoperatively (n = 13, 52%) or during follow-up (n = 12, 48%). Among these 24 patients, 17 had proximal leaks and the remaining 8 patients had distal leaks. These cases form the focus of this study.

RESULTS

Twenty-two leaks required endovascular intervention, with the following success rate: n-BCA, 12 of 13 cases (92.3%); extender cuffs, 4 of 5 cases (80%); coils with or without thrombin, 3 of 4 cases (75%). In one patient with persistent endoleak despite attempted endovascular intervention the device ultimately was surgically explanted, and the patient did well. Of six patients with endoleak initially managed expectantly, two eventually underwent attempts at definitive intervention, both with n-BCA. Three sealed spontaneously before definitive intervention could be performed; and in one 97-year-old patient who refused intervention, the aneurysm subsequently ruptured and the patient died. In total, 13 patients with type I endoleak underwent n-BCA transcatheter embolotherapy. No serious complications were directly related to this therapy. Colon ischemia developed in one patient, and was believed to be a result of thromboembolism during wire and catheter manipulation rather than n-BCA treatment. Twelve of these 13 leaks remain sealed at mean follow-up of 5.9 months (range, 0-19 months).

CONCLUSION

Our initial use of n-BCA occlusion suggests that it may be an effective and safe method of treatment of type I endoleak after EVAR. In particular, n-BCA embolotherapy may be especially useful in treating type I endoleak not amenable to placement of extender cuffs. Larger case series and longer follow-up are needed before this treatment is more broadly recommended. Type I endoleak after EVAR can be treated successfully with a variety of endovascular methods, and surgical explantation is rarely required.

Technique and results of transfemoral superselective coil embolization of type II lumbar endoleak

OBJECTIVE

This study was undertaken to describe the technique of transfemoral superselective coil embolization of type II endoleak and its influence on abdominal aortic aneurysm diameter.

METHODS

Over 23 months, 104 aortic stent grafts were deployed to exclude abdominal aortic aneurysms, at an academic medical center. Increase in aneurysm diameter and perigraft findings on contrast material-enhanced computed tomography scans prompted arteriography. Procedures were performed solely by vascular surgeons in a surgical angiography suite. In 7 patients aneurysm access was via the iliolumbar branches of the internal iliac artery, and in 1 patient aneurysm access was via the inferior mesenteric artery through the arc of Riolan from the superior mesenteric artery. Coaxial catheters were placed to gain access to the aneurysm (8F to 5F to 3F, or 5F to 3F). A 3F Tracker18 was the most distal catheter through which an assortment of 0.018 microcoils were deployed within the aneurysm, and the origin of the feeding vessels when possible.

RESULTS

Aneurysm diameter increased 0.48 +/- 0.2 cm over 10.8 +/- 5 months before superselective coil embolization. In 6 of 8 patients superselective coil embolization embolization resulted in a mean decrease in aneurysm diameter of 1.3 +/- 1.2 cm over 9 +/- 3.2 months. Failure was presumed due to inability to reach the aneurysm sac in 1 patient and was associated with oral anticoagulation in 1 other patient.

CONCLUSION

Proper identification of the source of type II endoleak and its complete occlusion, combined with aneurysm sac coiling, may result in prompt decrease in aneurysm size.

Does endograft support alter the rate of aneurysm sac shrinkage after endovascular repair?

PURPOSE

To test the hypothesis that stent-graft support influences sac shrinkage independent of endoleak rates after endovascular repair of abdominal aortic aneurysms (AAA).

METHODS

Ninety AAA patients underwent treatment with bifurcated endoluminal devices at our institution between October 1996 and February 1999. Fifty-two patients were treated using a nonsupported (NS) Ancure endograft and 38 using a fully supported (FS) Excluder endograft. Computed tomographic (CT) scans were obtained during the first postoperative month and at 6, 12, and 24-month intervals. Aneurysm diameter was measured as the minor axis of the largest AAA axial slice on the CT scan. Six, 12, and 24-month sac sizes were compared to the first postoperative evaluation.

RESULTS

Successful endoluminal graft placement was accomplished in all patients. The two groups were matched for age, anatomical criteria, and comorbidities except for baseline AAA size: the mean diameter was 5.4 cm in the NS group and 5.0 cm for the FS group (p<0.01). Endoleak rates were 25% (13/52) in the NS group and 18% (7/38) in the FS group (p<0.05) at 1 month. All endoleaks that did not resolve spontaneously at 6 months were treated. Initial endoleak status did not affect the sac shrinkage rates at the 12 and 24-month evaluations. At 2 years, the NS group had greater shrinkage of the sac (1.2 cm) versus the FS cohort (0.3 cm, p<0.05). In addition, more patients in the NS group had sac shrinkage >or =5 mm (83% versus 18%, p<0.05).

CONCLUSIONS

Despite a higher endoleak rate, the nonsupported Dacron Ancure endografts were associated with greater sac shrinkage at up to 24 months following implantation.

Preoperative embolization of collateral side branches: a valid means to reduce type II endoleaks after endovascular AAA repair

PURPOSE

To report the results of preprocedural embolization of collateral branches arising from abdominal aortic aneurysms (AAA) scheduled for endovascular repair.

METHODS

Twenty-three consecutive AAA patients (all men; mean age 73 years, range 56-82) had coil embolization of patent lumbar and inferior mesenteric arteries (IMA) in a staged procedure prior to endovascular repair. Embolization with microcoils was attempted in 37 of the 52 identified lumbar arteries and 14 of 15 inferior mesenteric arteries. Follow-up included biplanar abdominal radiography, spiral computed tomography, and duplex ultrasonography at 1, 30, 90, and 180 days after the stent-graft procedure and at 6-month intervals thereafter.

RESULTS

Successful embolization was obtained in 24 (65%) of lumbar arteries, while all 14 (100%) IMAs were occluded with coils. No complication was associated with embolotherapy. Over a mean 17-month follow-up of 22 patients (1 intraoperative death), there was only 1 (4.5%) type II endoleak from a patent lumbar artery, with no sac expansion after 2 years. There were 4 (18%) type I and 1 (4.5%) type III endoleaks.

CONCLUSIONS

The embolization of side branches arising from an infrarenal aortic aneurysm before endovascular repair is feasible, with a high success rate; this maneuver may play a relevant role in reducing the rate of type II endoleak, improving long-term outcome.

Aortoenteric fistula due to endoleak coil embolization after endovascular AAA repair

PURPOSE

To report a late complication associated with embolization coils used to treat an endoleak after endovascular abdominal aortic aneurysm (AAA) repair.

CASE REPORT

A 79-year-old man with a 5.8-cm AAA underwent endovascular repair with an Ancure graft in 1997. A persistent type I endoleak was identified on serial postoperative computed tomographic scans. Three transarterial coil embolization procedures were performed to treat an endoleak from the proximal and right distal attachment sites with outflow by the inferior mesenteric and lumbar arteries. Coil embolization was ultimately successful in sealing the endoleak, and the AAA decreased in size. Four years later, the patient developed an aortoenteric fistula due to erosion of the metallic embolization coils into the duodenum. The endograft was explanted and an extra-anatomical bypass inserted.

CONCLUSIONS

Coil embolization to treat endoleaks can, on rare occasions, be the cause of aortoenteric fistula. Lifelong follow-up of stent-graft patients is required.

Transcatheter embolization of an aortobronchial fistula with N-butyl cyanoacrylate

Aortobronchial fistula is a fatal complication after thoracic aortic surgery. So far, treatment options for aortobronchial fistula have included surgical and endovascular stent-graft methods. Herein, a case of an aortobronchial fistula with life-threatening hemoptysis managed with transcatheter embolization of the fistula with N-butyl cyanoacrylate is reported. For the patient with an aortobronchial fistula who cannot be treated by surgical or endovascular stent-graft methods, transcatheter embolization of the fistula may be the only available life-saving method.

Treatment of abdominal aortic anastomotic pseudoaneurysm with percutaneous coil embolization

Intraabdominal anastomotic pseudoaneurysms continue to be a late complication of aortic reconstructive procedures. Early surgical repair is critical but is associated with high operative mortality rates. We present a patient who was diagnosed with a distal anastomotic pseudoaneurysm 13 months after transabdominal repair of a symptomatic abdominal aortic aneurysm. Because of the poor operative risk, the patient was considered for a less invasive approach and underwent coil embolization of the abdominal aortic anastomotic pseudoaneurysm. The patient remains without recurrence of pseudoaneurysm 3.5 years later.

Durability of benefits of endovascular versus conventional abdominal aortic aneurysm repair

PURPOSE

Endovascular abdominal aortic aneurysm (AAA) repair is reported to result in less initial patient morbidity and a shorter hospital length of stay (LOS) when compared with conventional AAA repair. We sought to examine the durability of this result during the intermediate follow-up interval.

METHODS

The records of all admissions for all patients who underwent AAA repair during a 26-month interval were reviewed.

RESULTS

Three hundred thirty-seven (337) patients underwent procedures to repair AAAs (163 open and 174 endovascular). Endovascular procedures were performed with a variety of devices (Talent, 108; Ancure, 36; AneuRx, 26; Zenith, 2; and Cordis, 2) and configurations (141 bifurcated and 33 aortomonoiliac). The mean follow-up period was 10.6 months (endovascular repair) and 12.3 months (open repair). LOS did not significantly vary by device (P =.24 to P =.92) or configuration (P =.24). The initial median LOS for procedures was significantly shorter (P =.009) for endovascular repairs (5 days) than for open procedures (8 days). However, the patients who underwent endovascular repair were more likely to be readmitted during the follow-up interval when compared with patients who underwent open procedure. The readmission-free survival rate after AAA repair at 12 months was 95% for patients for open AAA repair versus 71% for patients for endovascular repair (P <.001). If the total hospital days were compared, including the initial and all subsequent AAA-related admissions, there was no significant difference for mean LOS for patients who underwent endovascular versus open AAA procedures (11 days versus 13.6 days; P =.21). The patients for endovascular AAA repair most commonly needed readmission for treatment of endoleak (n = 31), wound infection (n = 12), and graft limb thrombosis (n = 9). Although women had similar LOS to men for endovascular repair (P =.44), they had longer initial LOS for open AAA repair (15 versus 10 days; P =.03). After endovascular repair, women were more likely than men to be readmitted by 12 months (51% versus 71% readmission-free survival rate; P =.03) and they had longer LOS on readmission (13.2 versus 5.2 days; P =.006). No gender differences were identified for patients after open AAA repair regarding readmission-free survival rate (P =.09) or LOS on readmission (P =.98).

CONCLUSION

Although initial LOS was shorter for the patients who underwent endovascular as compared with conventional AAA repair, this advantage was lost during the follow-up interval because of frequent readmission for the treatment of procedure-related complications, chiefly endoleak. These readmissions frequently involved the performance of additional invasive procedures. Gender differences existed regarding LOS and the likelihood of complications after open and endovascular AAA repair.

Treatment of type 2 endoleaks after endovascular repair of abdominal aortic aneurysms: comparison of transarterial and translumbar techniques

OBJECTIVE

The exact significance of collateral endoleaks is unknown and a topic of great debate. Because of this uncertainty, some physicians choose to watch and wait while others aggressively treat these leaks. The purpose of this investigation was the evaluation of the efficacy of the two techniques used in the treatment of collateral endoleaks that occur after endovascular aneurysm repair.

METHODS

Patients with 33 angiographically proven type 2 endoleaks underwent treatment with either transarterial inferior mesenteric artery embolization (n = 20) or direct translumbar embolization (n = 13) during an 18-month period. Embolization success was defined as resolution of endoleak on all subsequent computed tomography angiogram results. The likelihood of embolization failure between the two treatments was expressed as a risk ratio and was compared with Fisher exact test.

RESULTS

Sixteen of 20 transarterial inferior mesenteric artery embolizations (80%) failed with recanalization of the original endoleak cavity over time. A single failure (8%) in the direct translumbar embolization group occurred in a patient in whom a new attachment site leak developed. The remaining 12 translumbar endoleak embolizations (92%) were successful and durable, with a median follow-up period of 254 days. The patients who underwent transarterial inferior mesenteric artery embolization were significantly more likely to have persistent endoleak than were the patients who underwent treatment with direct translumbar embolization (risk ratio, 4.6; 95% confidence interval, 1.9 to 11.2; P =.0001).

CONCLUSION

The transarterial embolization of inferior mesenteric arteries for the repair of type 2 endoleaks is ineffective and should not be performed. Direct translumbar embolization of the endoleak is effective in the elimination of type 2 leaks and should be the therapy of choice when aggressive endoleak management is indicated.

Intraoperative proximal endoleaks during AAA stent-graft repair: evaluation of risk factors and treatment with Palmaz stents

PURPOSE

To study factors that might contribute to intraoperative proximal type I endoleak and to evaluate the placement of giant Palmaz stents as a therapeutic option.

METHODS

Thirty-three patients (30 men; median age 72 years, range 50-85) with abdominal aortic aneurysms underwent implantation of fully supported Gianturco Z-stent-based endografts (12 custom-made aortomonoiliac and 21 bifurcated Zenith devices). Ten (30%) patients were treated for intraoperative proximal endoleaks. Stent-graft oversizing and neck angulation, length, and shape were compared between patients with and without leaks.

RESULTS

In 9 cases, the endoleaks were successfully treated with intraoperative placement of Palmaz stents without complications. In 1 patient, a leak that was resolved intraoperatively with balloon dilation reappeared 1 month later; a Palmaz stent was deployed successfully. Stent-graft oversizing did not differ significantly between patients who developed proximal endoleaks and those who did not (median 4.0 mm in both groups, p = 0.47). Median neck length was 21.0 mm in patients with endoleak and 28.0 mm in those without (p > 0.99). Median neck angulation was 30 degrees in both groups (p = 0.33), and the presence of a conical aneurysm neck was not significantly different (2/10 versus 6/23, p > 0.99). All aneurysms remained excluded at a median follow-up of 13 months (range 6-24).

CONCLUSIONS

Stent-graft oversizing and neck morphology (length, angulation, and conical shape) do not seem to correlate with the incidence of proximal type I endoleaks. Palmaz stent placement appears to be a feasible and safe treatment option for this complication.

Displacement of coils into the lung during embolotherapy: clinical importance and follow-up with helical CT

RATIONALE AND OBJECTIVES

The authors performed this study to evaluate the clinical importance and computed tomographic (CT) appearance of coils displaced into the lung during embolotherapy.

MATERIALS AND METHODS

The authors retrospectively studied clinical charts and serial chest images from 25 consecutive patients after coil embolization. Chest radiography was performed in all patients, whereas helical chest CT was performed only in patients in whom dislocated coils were visible on chest radiographs. Coils were applied for the treatment of peripheral arteriovenous (AV) malformations and fistulas (n = 9), renal AV malformations or fistulas (n = 8), and primary or secondary tumors (n = 8). Clinical charts were analyzed for short- and long-term symptoms; chest radiographs and CT scans were reviewed for signs indicative of pulmonary infarction.

RESULTS

None of the patients had clinical symptoms suggestive of pulmonary infarction. In two of the 25 patients (8%), displaced coils were seen in the pulmonary vasculature at chest radiography; these patients had been treated for renal AV fistula and peripheral AV fistula, respectively. One patient had two coils in the left hemithorax (upper and lower lobe), and the other patient had two coils in the right hemithorax (middle lobe). Neither of the patients had abnormalities suggestive of pulmonary infarction at helical CT.

CONCLUSION

Chest radiography can help confirm the presence of coils displaced to the pulmonary vasculature during embolotherapy. Helical CT can also help rule out the presence of coil-associated pulmonary infarction.

Endovascular stent-graft in abdominal aortic aneurysms: the relationship between patent vessels that arise from the aneurysmal sac and early endoleak

PURPOSE

To determine the association of patent sac branch vessels (lumbar and inferior mesenteric arteries [IMAs]) with early endoleak rate after stent-graft repair of abdominal aortic aneurysm (AAA).

MATERIALS AND METHODS

Pre- and postoperative computed tomographic (CT) angiograms in 158 patients who underwent stent-graft AAA repair were retrospectively reviewed to determine the preoperative patency of IMAs and other sac branch vessels (feeders) and presence or absence of immediate postoperative endoleak. Relationships of early endoleak rate with total branch vessel, IMA, and lumbar artery patency and graft type were evaluated.

RESULTS

There was a significant association between patency of sac feeders and rate of early endoleak, especially type 2. As total patent feeders increased from zero to three to four to six, total endoleak rate increased from 6% (one of 17) to 35% (30 of 86); type 2 endoleak rate, from 0% to 25%. IMA patency was significantly associated with total early endoleak rate. Increasing lumbar artery patency also was associated with significantly higher total and type 2 endoleak rates: With zero to three lumbar arteries, the total endoleak rate was 17% and type 2 endoleak rate was 13%, as compared with 60% and 50%, respectively, with more than six patent lumbar arteries.

CONCLUSION

Sac branch vessel patency is associated with significantly higher early total and type 2 endoleak rates after stent-graft repair of AAAs; thus, patent sac branches play an important role in the pathogenesis of endoleaks.

Long-term fate of the aneurysmal sac after endoluminal exclusion of abdominal aortic aneurysms

PURPOSE

Shrinkage of an abdominal aortic aneurysm (AAA) is the hallmark of successful endoluminal treatment. Our goal was to prospectively assess the midterm to long-term shrinkage of the AAA sac after endovascular repair.

METHODS

A total of 123 patients with AAA underwent endoluminal treatment with the Ancure device at our institution between February 1996 and February 2000. At least a 1-year follow-up was available for 70 of the 123 patients. AAA sac size, presence of endoleaks, calcifications, and outcome data were collected on these patients at 6, 12, 24, and 36 months after repair and compared with the preoperative AAA size and characteristics. All endoleaks found at the 6-month follow-up visit were treated aggressively with embolotherapy. An AAA sac regression of 0.5 cm or more was considered the minimum measurable decrease. Regression of the sac diameter to 3.5 cm or less was considered a complete collapse of the sac.

RESULTS

Successful endoluminal repair was accomplished in 119 of 123 patients. The mortality rate was 0.8% (1/123). There was a steady decrease in AAA sac size from baseline (5.56 +/- 0.1 cm), to 6 months (5.0 +/- 0.14 cm, P =.0006), to 12 months (4.65 +/- 0.13 cm, P =.04), and to 24 months (4.26 +/- 0.16 cm, P =.03). At 24 months, 74% (29/39) had a decrease in sac size of 0.5 cm or more, with 28% (11/39) complete collapse. Patients with initial endoleaks had the same likelihood of regression of sac size (> or = 0.5 cm) when compared with the group of patients with no endoleaks at the 24-month evaluation (64% vs 76%, P =.09).

CONCLUSION

Endoluminal AAA repair resulted in a significant reduction in sac size that continues up to 2 years. Significant shrinkage occurs as early as 6 months after placement. The initial presence of endoleaks does not predict the lack of sac regression.

Endovascular repair of the abdominal aortic aneurysm with the ancure endograft: CT follow-up of perigraft flow and aneurysm size at 6 months

PURPOSE

Perigraft flow--flow outside the graft lumen but contained within the abdominal aortic aneurysm (AAA)--is a potential complication after endovascular repair of AAA. Such flow may permit AAA growth and rupture. The purpose of this study is to evaluate with computed tomography (CT) the rate of spontaneous closure of perigraft flow and the effect of persistent flow on AAA diameter.

MATERIALS AND METHODS

During a 30-month period, the authors evaluated all CT scans in 50 patients who underwent AAA repair using the Ancure endograft system. CT was performed at discharge, 6, 12, and 24 months, and at 3 months if there was perigraft flow at discharge. Scans were reviewed for the presence, size, and location of perigraft flow, and measurement of AAA diameter. Transcatheter embolization was performed on those patients with persistent leak at 6 months.

RESULTS

Sixteen (32%) of 50 patients demonstrated perigraft flow on CT performed within 72 hours of placement. Resolution of perigraft flow by 6 months was found in nine (56%) of the 16 patients, in whom AAA size had decreased in five, had increased in none, and was unchanged in four. Seven patients had persistent leaks at 6-month CT; AAA size had decreased in one, had increased in one, and was unchanged in five. In 34 patients without leaks, AAA size had decreased in nine, had increased in one, and was unchanged on 24. There was no statistically significant difference for the relationship between resolution or persistence of perigraft flow and subsequent course of AAA diameter (P = .16).

CONCLUSIONS

Although perigraft flow is frequently seen (32%) early after repair of AAA with the Ancure system, spontaneous resolution by 6 months occurs in 56% of cases. AAA size decreased in a larger percentage of patients in whom perigraft leak was absent or resolved by 6 months compared with those in whom perigraft leak persisted at 6 months.