Aortic Arch and Descending Thoracic Aortic Aneurysms: Experience with Stent Grafting for Second-Stage “Elephant Trunk” Repair

Snare-assisted thoracic endovascular aortic repair for redirection of a false lumen elephant trunk

In recent years, a hybrid approach to the classic two-stage elephant trunk technique has come into favor for treatment of thoracic aortic dissection. During the first stage, inadvertent intraoperative placement of the elephant trunk into the false lumen can occur on rare occasions, resulting in untoward difficulties during the second stage of the procedure. We describe here a snare-assisted technique for endovascular salvage of an elephant trunk that had inadvertently been placed in the false lumen of a chronic aortic dissection.

Elephant trunk technique for hybrid aortic arch repair

The original elephant trunk technique was developed by Borst in 1983 for the treatment of aortic arch aneurysms. This technique reduced operative risks, but was associated with cumulative mortality rates of 6.9 % for the first stage and 7.5 % for the second stage. Patients also waited a long time between two major surgical procedures. Only 50.4 % of patients underwent the second-stage surgery, and there was a significant interval mortality rate of 10.7 %. With the advent of stent-graft techniques, two different hybrid elephant trunk techniques were developed. One technique is first-stage elephant trunk graft placement followed by second-stage endovascular completion. The conventional elephant trunk graft provides a good landing zone for the stent-graft, and endovascular completion is a useful alternative to conventional second-stage surgery. This method has few major complications, and a postoperative paraplegia rate of 1.1 %. The other technique is the frozen elephant trunk technique. This technique eliminates the need for subsequent endovascular completion, and is particularly useful for the treatment of acute type A dissection because it can achieve a secure seal. However, it is associated with a higher rate of spinal cord ischemia than other methods such as the original elephant trunk technique. The left subclavian artery (LSA) is often lost when performing a hybrid elephant trunk procedure. Revascularization of the LSA should be performed to prevent arm ischemia and neurological complications such as paraplegia or stroke, although the level of evidence for this recommendation is low.

Results with an algorithmic approach to hybrid repair of the aortic arch

OBJECTIVE

Hybrid repair of the transverse aortic arch may allow for aortic arch repair with reduced morbidity in patients who are suboptimal candidates for conventional open surgery. We present our results with an algorithmic approach to hybrid arch repair, based on the extent of aortic disease and patient comorbidities.

METHODS

Between August 2005 and January 2012, 87 patients underwent hybrid arch repair by three principal procedures: zone 1 endograft coverage with extra-anatomic left carotid revascularization (zone 1; n = 19), zone 0 endograft coverage with aortic arch debranching (zone 0; n = 48), or total arch replacement with staged stented elephant trunk completion (stented elephant trunk; n = 20).

RESULTS

The mean patient age was 64 years, and the mean expected in-hospital mortality rate was 16.3% as calculated by the EuroSCORE II. Of operations, 22% (n = 19) were nonelective. Sternotomy, cardiopulmonary bypass, and deep hypothermic circulatory arrest were required in 78% (n = 68), 45% (n = 39), and 31% (n = 27) of patients to allow for total arch replacement, arch debranching, or other concomitant cardiac procedures, including ascending with or without hemiarch replacement in 17% (n = 8) of patients undergoing zone 0 repair. All stented elephant trunk procedures (n = 20) and 19% (n = 9) of zone 0 procedures were staged, with 41% (n = 12) of patients undergoing staged repair during a single hospitalization. The 30-day/in-hospital rates of stroke and permanent paraplegia or paraparesis were 4.6% (n = 4) and 1.2% (n = 1). Of 27 patients with native ascending aorta zone 0 proximal landing zone, three (11.1%) experienced retrograde type A dissection after endograft placement. The overall in-hospital mortality rate was 5.7% (n = 5); however, 30-day/in-hospital mortality increased to 14.9% (n = 13) owing to eight 30-day out-of-hospital deaths. Native ascending aorta zone 0 endograft placement was found to be the only univariate predictor of 30-day in-hospital mortality (odds ratio, 4.63; 95% confidence interval, 1.35-15.89; P = .02). Over a mean follow-up period of 28.5 ± 22.2 months, 13% (n = 11) of patients required reintervention for type 1A (n = 4), type 2 (n = 6), or type 3 (n = 1) endoleak. Kaplan-Meier estimates of survival at 1 year, 3 years, and 5 years were 73%, 60%, and 51%.

CONCLUSIONS

Hybrid aortic arch repair can be tailored to patient anatomy and comorbid status to allow complete repair of aortic pathology, frequently in a single stage, with acceptable outcomes. However, endograft placement in the native ascending aorta is associated with high rates of retrograde type A dissection and 30-day/in-hospital mortality and should be approached with caution.

Aortic arch replacement and elephant trunk procedure: an interdisciplinary approach to surgical reconstruction, perfusion strategies and blood management

Surgical treatment of patients who present with large aneurysms of the ascending aorta, transverse arch and descending aorta, including the thoracic and abdominal aorta typically consists of a two-staged elephant trunk procedure. Typically, these operations are lengthy, requiring long cardiopulmonary bypass times, deep hypothermic circulatory arrest and multiple anastamotic suture lines, which increases the risks for coagulopathic bleeding and the need for massive transfusions. The purpose of this report is to describe our approach, involving advanced surgical techniques and the innovative perfusion considerations as well as modified blood management strategies to minimize perioperative blood loss and the need for transfusions. All of the above will highlight critical cardiac team communications. An ever-evolving case requires forward thinking, revised judgments, open discussion and the continued involvement of all team members. In turn, this ensures evidence-based medical and perfusion practices that lead to achieving a positive peri-operative course, with optimal blood conservation.

Erosion of elephant trunk Dacron graft limb by thoracic endograft causing acute aneurysm expansion

We recently treated a patient in whom a Gore TAG thoracic endograft (W.L. Gore and Assoc, Flagstaff, Arix) had been used to repair a descending thoracic aneurysm as the second stage of a hybrid procedure. This patient had previously undergone repair of ascending and aortic arch aneurysms, with an elephant trunk graft limb placed in the descending thoracic aorta for subsequent repair of the descending thoracic aneurysm. Eight months after placement of the thoracic endograft, the patient presented with an acutely expanding and symptomatic thoracic aneurysm. The patient was operated on urgently. The proximal portion of the endograft had eroded into the previously placed Dacron elephant trunk limb. The proximal portion of the endograft was removed and was replaced with a Dacron graft. The management of this patient forms the basis of this report.

Endovascular repair of a ruptured descending thoracic aortic aneurysm in a patient with an ascending aortic aneurysm: hybrid open arch reconstruction with simultaneous thoracic stent-graft deployment within elephant trunk

Endovascular repair of the thoracic aorta is now widely practiced. The extension of this technique to emergent settings is in evolution. Pathology of the ascending and transverse aortic arch may preclude thoracic aortic stent grafting due to the lack of a proximal seal zone. Several hybrid open/endovascular approaches have been described. We recently encountered the difficult case of a contained rupture of a 6.8 cm descending thoracic aortic aneurysm in a 60-year-old patient with aneurysmal degeneration of the ascending and transverse aortic arch. This patient was treated with a hybrid approach of open ascending and transverse arch reconstruction along with simultaneous stent-graft repair of the descending thoracic aorta. The open repair established an excellent proximal landing zone by use of the "elephant trunk" technique. This technique also allowed direct suture fixation of the stent graft to the arch graft to prevent stent-graft migration. This hybrid surgical approach was successful and avoided the cumulative morbidity that a left thoracoabdominal approach would have added to the sternotomy. Further creative uses of these hybrid techniques will undoubtedly serve a larger role in the treatment of thoracic aortic pathology.

The hybrid elephant trunk procedure: A single-stage repair of an ascending, arch, and descending thoracic aortic aneurysm

Surgical repair of extensive aortic aneurysms requires a two-stage approach. We present the case of a single-stage repair using a hybrid procedure. This case demonstrates the technical feasibility of repairing properly selected extensive aortic aneurysms in a single procedure.

The Elephant Trunk Technique for Staged Repair of Complex Aneurysms of the Entire Thoracic Aorta

BACKGROUND

Extensive thoracic aortic aneurysms that involve the ascending, arch, and descending segments require challenging repairs associated with substantial morbidity and mortality. The purpose of this report is to evaluate contemporary outcomes after surgical repair of extensive thoracic aortic aneurysms using a two-stage approach with the elephant trunk technique.

METHODS

During a 15 1/2-year period, 148 consecutive patients underwent total aortic arch replacement using the elephant trunk technique. Seventy-six of these patients (51%, 76/148) returned for second-stage repair of the descending thoracic or thoracoabdominal aorta 4.9 +/- 7.5 months after the first stage.

RESULTS

Operative mortality after the proximal aortic stage was 12% (18/148). Seven patients (5%) had strokes. Among the patients who subsequently underwent distal aortic repair, operative mortality was 4% (3/76). Two patients (3%) developed paraplegia. Long-term survival after completing the second stage of repair was 70 +/- 6% at 5 years and 59 +/- 7% at 8 years.

CONCLUSIONS

Contemporary management of extensive thoracic aortic aneurysms using the two-stage elephant trunk technique yields acceptable short-term and long-term outcomes. This technique remains an important component of the surgical armamentarium.

Percutaneous Repair of Abdominal Aortic Pseudoaneurysm by Catheter-Based Delivery of Thrombin

PURPOSE

To present a case in which thrombin was injected percutaneously to treat an aortic pseudoaneurysm.

CASE REPORT

A 63-year-old man developed a large pseudoaneurysm in the abdominal aorta after surgical fenestration and patch aortoplasty for acute type B aortic dissection with malperfusion syndrome. Transcatheter delivery of 1500 units of thrombin resulted in complete thrombosis of the pseudoaneurysm sac. No complications occurred. Twelve months after the procedure, the pseudoaneurysm was completely resolved on computed tomography.

CONCLUSION

Thrombin continues to prove its safety and efficacy for the treatment of pseudoaneurysms at numerous anatomical sites, including the abdominal aorta.