Endovascular Stent-Graft Repair of Failed Endovascular Abdominal Aortic Aneurysm Repair

Elective endovascular aortic repair conversion for type Ia endoleak is not associated with increased morbidity or mortality compared with primary juxtarenal aneurysm repair

OBJECTIVE

Type Ia endoleak after endovascular aortic repair (EVAR) can be a challenging complication to manage, and due to concerns regarding morbidity and mortality of open surgical conversion (OSC), reports of complex endoluminal salvage techniques are increasing. Despite development of these endovascular remedial strategies, many patients ultimately require OSC. The purpose of this analysis was to outcomes of elective OSC for type Ia endoleak and compare them with elective primary open juxtarenal aneurysm repair (OJAR) to determine if these concerns are warranted.

METHODS

From 2000 to 2012, 54 patients underwent EVAR OSC at median time of 27 months (interquartile range, 9-55 months). Indications included endograft thrombosis in 2 (4%), intraoperative EVAR failure in 3 (6%), rupture in 5 (9%), graft infection in 6 (11%), and type Ia endoleak in 25 (all: 38 [70%]). Because many OSCs are performed for emergency indications without endovascular options, we chose elective type Ia endoleak patients as our study group. These 25 patients were compared with an elective OJAR cohort matched by anatomy and comorbidities. Primary end points were 30-day and 1-year mortality. Secondary end points included early complications, cross-clamp time, procedure time, blood loss, and length of stay.

RESULTS

Demographic and comorbidity data in the OSC and OJAR groups did not differ, with the exception that OJAR patients presented with smaller aneurysm diameter and a higher rate of chronic obstructive pulmonary disease (P = .03). OSC patients more frequently underwent a nontube graft repair (OSC, n = 20 [80%] vs OJAR, n = 6 [24%]; P = .0002), required longer procedure times (P = .03), and received more plasma transfusions (P = .03). The 30-day mortality was 4% in both groups (observed difference in rates, 0%; 95% confidence interval for difference in mortality rates, -14.0% to 14.0%; P = 1). A similar rate of major complications occurred (OSC, n = 9 [36%] vs OJAR, n = 8 [32%]; P = 1). One-year survival was 83% in OSC and 91% in OJAR (observed difference, 7%; 95% confidence interval, -15% to 29%; P = .65).

CONCLUSIONS

Despite many advances in EVAR technology, the need for OSC persists and will likely become more common as older-generation devices fail or providers attempt EVAR in more anatomically complex patients. Elective OSC for type Ia endoleak can be technically challenging but is not associated with increased morbidity or mortality compared with OJAR in appropriately selected patients. These results should be considered before pursuing complex endovascular remediation of EVAR failures.

Endovascular repositioning of a migrated stent graft using "endoanchor capture"

Endovascular aneurysm repair is increasingly used to treat patients harboring abdominal aortic aneurysms with severe comorbidities that make them unfavorable candidates for open repair. Graft-related complications in these patients also require unique solutions. We report the novel technique of "endoanchor capture" for successful repositioning of a migrated stent graft.

Secondary modification into aortouniiliac configuration to salvage failed endovascular aneurysm repair is safe and effective but not associated with higher intervention rates during long-term follow-up

BACKGROUND

Reports of secondary modifications into aortouniiliac configuration to salvage-failed endovascular aneurysm repair (EVAR) are limited. We evaluated long-term results after these procedures and compared them with those after primary aortouniiliac endografting (AUE).

METHODS

A retrospective review of all EVAR performed from March 1995 until July 2011 was conducted. Patients were included when primary AUE (group I) or modification into aortouniiliac configuration (group II) was done.

RESULTS

Data analysis obtained 27 group I and 23 group II patients. Salvage of failed EVAR could be achieved in 96% of group II patients, and mortality was zero. Frequency of adverse events and amount of interventions to maintain aneurysm exclusion were not increased after secondary AUE. Kaplan-Meier estimates for long-term survival between groups were comparable (P = .36).

CONCLUSIONS

Secondary AUE allows correction of graft-related endoleaks potentially leading to late aneurysm rupture. Complications and adverse events throughout long-term follow-up were not necessarily increased when compared with primary AUE.

Endovascular aneurysm repair in emergent ruptured abdominal aortic aneurysm with a 'real' hostile neck and severely tortuous iliac artery of an elderly patient

Background

Endovascular aneurysm repair (EVAR) has been a revolutionary development in the treatment of abdominal aortic aneurysms (AAAs). Meanwhile, unfavorable anatomy of the aneurysm has always been a challenge to vascular surgeons, and the application of EVAR in emergent and elderly patients are still in dispute.

Case presentation

A 79-year-old woman presented as an emergency of abdominal pain with acute hypotension, heart rate elevation and a rapid decrease of hemoglobin. Emergent computed tomographic angiography (CTA) showed a ruptured AAA (rAAA) extending from below the opening of bilateral renal arteries down to the celiac artery and elongated to both common iliac arteries. The hostile neck and severely tortuous iliac artery made the following procedure a great challenge. An emergent endovascular approach was performed in which an excluder aortic main body was deployed below the origin of the bilateral renal arteries covering the ruptured aortic segment. Two iliac legs were placed superior to the opening of the right hypogastric respectively. In order to avoid the type Ib endoleak, we tried to deploy another cuff above the bifurcation of the iliac artery. However, the severely tortuous right iliac artery made this procedure extremely difficult, and a balloon-assisted technique was used in order to keep the stiff wire stable. Another iliac leg was placed above the bifurcation of the left iliac artery. The following angiography showed a severe Ia endoleak in the proximal neck and therefore, a cuff was deployed distal to opening of the left renal artery with off-the-shelf solution. The patient had an uneventful recovery with a resolution of the rAAA. She is well and symptom-free 6 months later.

Conclusion

Endovascular aneurysm repair (EVAR) in emergent elderly rAAA with hostile neck and severe tortuous iliac artery is extremely challenging, and endovascular management with integrated technique is feasible and may achieve a satisfactory early result.

Use of a bifurcated endovascular graft for treatment of endograft migration with major endoleak

The purpose of this study was to describe the use of a bifurcated endovascular graft to treat endograft migration with major endoleaks. We present four patients who presented at a mean of 72.0 months after their initial endovascular abdominal aortic aneurysm repair. Three patients had type I endoleaks resulting from proximal attachment failure and graft migration. A fourth patient had separation of a proximal aortic cuff from a migrated main body device resulting in a type III endoleak. All were treated with a bifurcated Zenith (Cook Medical Incorporated, Bloomington, IN, USA) endovascular graft. There was 100% technical success with no perioperative complications. On follow-up, one patient died of unrelated causes at five months. The mean survival for the remaining three patients was 37 months. In conclusion, treatment with a bifurcated Zenith endograft has advantages over the use of an aortic cuff or aortouniiliac reconstruction. To perform this technique, there must be a sufficient distance between the proximal landing zone and the flow divider of the migrated endograft to allow for deployment of the Zenith device. While there remain limitations in its applicability, the use of a bifurcated endovascular graft is a viable alternative for endovascular salvage in treatment of endograft migration with major endoleaks.

Endovascular abdominal aortic aneurysm repair: nonenhanced volumetric CT for follow-up

PURPOSE

To evaluate the clinical usefulness of volumetric analysis at nonenhanced computed tomography (CT) as the sole method with which to follow up endovascular abdominal aortic aneurysm repair (EVAR) and to identify endoleaks causing more than 2% volumetric increase from the previous volume determination.

MATERIALS AND METHODS

The study had institutional review board approval. Images were reviewed retrospectively in a HIPAA-compliant manner for 230 CT studies in 70 patients (11 women, 59 men; mean age, 74 years) who underwent EVAR. The scannning protocol consisted of three steps: (a) contrast material-enhanced CT angiography before endovascular stent placement, (b) contrast-enhanced CT angiography 0-3 months after repair to depict immediate complications, and (c) nonenhanced CT at 3, 6, and 12 months after repair. At each follow-up visit, immediate aortic volume analysis was performed. If the interval volumetric change was 2% or less, no further imaging was performed. If the volume increased by more than 2% on the nonenhanced CT image, contrast-enhanced CT angiography was performed immediately to identify the suspected endoleak. Confidence intervals (CIs) were obtained by using bootstrapping to account for repeated measurements in the same patients.

RESULTS

Mean volume decrease was -3.2% (95% CI: -4.7%, -1.9%) in intervals without occurrence of a clinically relevant endoleak (n = 183). Types I and III high-pressure endoleaks (n = 10) showed a 10.0% (95% CI: 5.0%, 18.2%) interval volumetric increase. Type II low-pressure endoleaks (n = 37) showed a 5.4% (95% CI: 4.6%, 6.2%) interval volumetric increase. Endoleaks associated with minimal aortic volume increase of less than 2% did not require any intervention. This protocol reduced radiation exposure by approximately 57%-82% in an average-sized patient.

CONCLUSION

Serial volumetric analysis of aortic aneurysm with nonenhanced CT serves as an adequate screening test for endoleak, causing volumetric increase of more than 2% from the volume seen at the previous examination.