Distal aortic arch replacement for aneurysmal disease: the value of preparatory carotid subclavian reconstruction

Repair of Distal Aortic Arch Aneurysms by Left Subclavian Artery Transposition with Stented Elephant Trunk Implantation

BACKGROUND

Repair of distal aortic arch aneurysms remains technically challenging using conventional open surgery due to its location. Several techniques, including a conventional prosthetic graft replacement and a hybrid technique, were introduced to manipulate this lesion. We retrospectively reviewed our experience with left subclavian artery (LSCA) transposition with stented elephant trunk implantation for repair of distal aortic arch aneurysms.

METHODS

From May 2009 to December 2014, 9 men (mean age 55 ± 16 years) with distal aortic arch aneurysms underwent LSCA transposition with stented elephant trunk implantation under hypothermic cardiopulmonary bypass with antegrade selective cerebral perfusion via a median sternotomy. One case had a history of endovascular abdominal aortic repair.

RESULTS

There was no in-hospital death. The mean time of mechanical ventilation and intensive care unit stay was 22 ± 9 and 53 ± 17 hr, respectively. No severe complications occurred in this group. All patients survived and were discharged. No patient died during the follow-up period. Postoperative computed tomography revealed good patency of the anastomotic site between the LSCA and the left common carotid artery.

CONCLUSIONS

Satisfactory surgical results and follow-up outcomes were achieved by simultaneous repair of proximal aortic lesions and complete seal of the lesion involving the distal aortic arch and proximal descending aorta using LSCA transposition with implantation of a stented elephant trunk. Encouraging outcomes favor this technique for distal aortic arch aneurysm.

Can the Left Subclavian Artery be Safely Covered during Endovascular Repair of the Descending Thoracic Aorta?

Objective

Routine preoperative carotid-subclavian bypass or transposition is frequently recommended in patients undergoing endovascular repair of the descending thoracic aorta (DTA). We reviewed our comprehensive thoracic endografting experience with regards to coverage of the left subclavian artery (LSA) to assess whether mandatory preoperative carotid-subclavian bypass or transposition is necessary.

Methods

Between February 2000 and November 2005, 255 patients were successfully treated with an endoluminal graft (ELG) to the DTA. Indications for intervention included atherosclerotic aneurysms (109/255, 42.7%), acute and chronic dissections (75/255, 29.4%), miscellaneous (41/255, 16.1%), and penetrating aortic ulcers (30/255, 11.8%). There were 151 males (151/255, 59.2%) and 104 females (104/255, 40.8%) with a mean age of 71 years (range, 23–91 years).

Results

The LSA was completely covered with an ELG in 71 patients (71/255, 27.8%) and partially covered in 47 patients (47/255, 18.4%). In patients who had complete coverage of the LSA, 30 patients (30/71, 42.3%) had acute or chronic Type B dissections, 26 patients (26/71, 36.6%) had aneurysms, 11 patients (11/71, 15.5%) had miscellaneous aortic pathologies, and 4 patients (4/71, 5.6%) had pseudoaneurysms associated with prior coarctation repair. Fifteen patients (15/255, 5.9%) underwent preoperative carotid-subclavian bypass or transposition and subsequently underwent complete coverage of the LSA with an ELG. One patient (1/56, 1.8%) with complete coverage of the LSA required elective postoperative carotid-subclavian bypass secondary to left arm claudication.

Conclusions

Routine preoperative carotid-subclavian bypass is not necessary, except in select patients with a patent left internal mammary artery to the left anterior descending artery bypass graft or contralateral vertebral artery disease.

Utility of left subclavian artery revascularization in association with endoluminal repair of acute and chronic thoracic aortic pathology

BACKGROUND

A rapidly increasing number of thoracic aortic lesions are now treated by endoluminal exclusion by using stent grafts. Many of these lesions abut the great vessels and limit the length of the proximal landing zone. Various methods have been used to address this issue. We report our experience with subclavian artery revascularization in association with endoluminal repair of acute and chronic thoracic aortic pathology.

METHODS

Thirty (43%) of 70 patients undergoing thoracic endovascular stent-graft placement from January 2001 to August 2005 had lesions adjacent to or involving the origin of the subclavian artery. The mean age was 62 years (range, 22-85 years; 63% were men, and 37% were women). This subgroup of 30 patients had indications for repair that included thoracic aortic aneurysm (n = 15), traumatic transection (n = 6), chronic dissection with pseudoaneurysm (n = 5), and acute dissection with intramural hematoma (n = 4). All 30 patients had the subclavian origin covered by the stent graft. In eight cases (27%), no effort was made to revascularize the subclavian artery before or during the endograft placement procedure. Twenty-three (77%) of 30 patients underwent subclavian to carotid artery transposition (n = 21) or bypass (n = 2) before (n = 12; average of 14 days before stent-graft placement), concomitant with (n = 10), or after (n = 1) the endovascular procedure. Physical examination and computed tomography scans were performed after surgery at 1, 6, and 12 months and annually thereafter. The mean follow-up was 18 months (range, 1-51 months).

RESULTS

Five acute complications occurred in the eight patients (63%) who had the subclavian artery covered without pre-endograft revascularization and included four patients who experienced stroke (accounting for the only death) and one patient who developed symptomatic subclavian-vertebral steal that necessitated transposition 7 months later. Two (9%) of the 23 patients who had subclavian revascularization experienced left-sided vocal cord palsies, and 1 patient (4%) developed lower extremity paraparesis secondary to spinal cord ischemia. No late endoleaks related to retrograde sac perfusion from the most distal great vessel have been identified in any patient.

CONCLUSIONS

Subclavian revascularization procedures can be performed with relatively low risk. Complications are rare, and patient recovery is rapid. Although this is not necessary in all cases, we advocate subclavian to carotid transposition when the aortic lesion is within 15 mm of the left subclavian orifice to prevent type II endoleak or perfusion of a dissected false lumen when the ipsilateral vertebral artery is patent and dominant or when coronary revascularization using an ipsilateral internal mammary artery is anticipated and in cases that necessitate extensive coverage of intercostals that contribute to spinal cord perfusion. Carotid to subclavian artery bypass should be reserved for patients with a patent internal mammary artery conduit perfusing a coronary vessel and should be combined with proximal subclavian ligation.