In Situ Laser Fenestration Is a Feasible Method for Revascularization of Aortic Arch During Thoracic Endovascular Aortic Repair

Abstract

Background: Reconstruction of the aortic major branches during thoracic endovascular aortic repair is complicated because of the complex anatomic configuration and variation of the aortic arch. In situ laser fenestration has shown great potential for the revascularization of aortic branches. This study aims to evaluate the feasibility, effectiveness, and safety of in situ laser fenestration on the three branches of the aortic arch during thoracic endovascular aortic repair.

Methods and results: Before clinical application, the polytetrafluoroethylene and Dacron grafts were fenestrated by an 810-nm laser system ex vivo, which did not damage the bare metal portion of the endografts and created a clean fenestration while maintaining the integrity of the endografts. In vivo, 6 anesthetized female swine survived after this operation, including stent-graft implantation in the aortic arches, laser fenestration, and conduit implantation through the innominate arteries and the left carotid arteries. Based on the animal experiments, in situ laser fenestration during thoracic endovascular aortic repair was successively performed on 24 patients (aged 33-86 years) with aortic artery diseases (dissection type A: n=4, type B: n=7, aneurysm: n=2, mural thrombus: n=7). Fenestration of 3 aortic branches was performed in 2 (8.3%) patients. Both the left carotid artery and the left subclavian artery were fenestrated in 6 (25%) patients. Only left subclavian artery fenestration surgery was done in 16 (66.7%) patients. Among these patients, 1 fenestration was abandoned secondary to an acute takeoff of the innominate artery in a type III aortic arch. The average operative time was 137±15 minutes. The technical success rate was 95.8% (n=23). No fenestration-related complications or neurological morbidity occurred after this operation. During a mean postoperative 10-month follow-up (range: 2-17 months), 1 patient died of severe pneumonia, and all the left subclavian artery and carotid artery stents were patent with no fenestration-related endoleaks upon computed tomography angiography images.

Conclusions: In situ laser fenestration is a feasible, effective, rapid, repeatable, and safe option for the reconstruction of aortic arch during thoracic endovascular aortic repair, which might be available to revascularize the 3 branches. However, follow-up periods should be extended to evaluate the robustness of this technique.

Keywords: aortic arch; aortic disease; aortic dissection; branch artery; covered stent; in situ laser fenestration; thoracic endovascular aortic repair.

Figure 1

Ex vitro laser fenestration on stent grafts of aortic arches. A, The laser catheter directly contacts the fabric of the stent graft; (B) the laser system was calibrated to excite the wavelength of 810 nm with 14 to 18 W of energy; (C) a proximal fenestration was produced and a balloon catheter, which was used as a landmark for entry into the lumen; (D) dilated with a balloon catheter; (E) general observation of the shape of the fenestration from the side; (F) general observation of the shape of the fenestration from the front.

Figure 2

In vivo laser fenestration on aortic arches during TEVAR in pigs. A, aortic angiography in AP view; (B) aortic angiography in left‐anterior oblique view; (C) 1 stent was implanted in the aortic arch and in situ laser fenestration; (D) balloon dilatation was performed to enlarge the fenestration; (E) a 0.035‐inch Stiff guidewire was exchanged; (F) position of the stent; (G) placement of a stent; (H) pigtail catheter was advanced to the ascending aorta; (I) aortic angiography showed the patency of the aortic arch branches; (J) after sacrificing the animals, the cohort of animals presented possible access sites of fenestration and stent placement. AP indicates anterior‐posterior; TEVAR, thoracic endovascular aortic repair.

Figure 3

In situ laser fenestration of LSA during TEVAR. A, CTA showed 1 patient had mural thrombus and ulcer; (B) aortic angiography in left‐anterior oblique view; (C) 1 stent was implanted in the aortic arch and in situ laser fenestration; (D) balloon dilatation was performed to enlarge the fenestration and a 0.035‐inch Stiff guidewire was exchanged; (E) placement of a stent and aortic angiography showed the patency of the aortic arch branches; (F and G) postoperative CTA presented possible access sites of fenestration and stent placement; (H) cross section of CTA showed that the in situ laser fenestrated LSA were patent. CTA indicates computed tomography angiography; LSA, left subclavian artery; TEVAR, thoracic endovascular aortic repair.

Figure 4

In situ laser fenestration of LCA and LSA during TEVAR. A, CTA showed that 1 patient had aortic dissection involved the LCA and LSA; (B) CTA images in back‐anterior oblique view; (C) cross section of CTA showed that the tear involved the LCA and LSA; (D) cross section of CTA showed aortic dissection involved the bilateral iliac artery; (E) aortic angiography in left‐anterior oblique view; (F) 1 stent was implanted in the aortic arch and in situ laser fenestration of LCA; (G) LCA stent placement and balloon dilatation was performed to enlarge the fenestration and a 0.035‐inch Stiff guidewire was exchanged in LSA; (H) aortic angiography showed the patency of the aortic arch branches. CTA indicates computed tomography angiography; LCA, left carotid artery; LSA, the left subclavian artery; TEVAR, thoracic endovascular aortic repair.

Figure 5

In situ laser fenestration of the innominate artery, LCA, and LSA during TEVAR. A, CTA showed that 1 patient had aortic dissection that involved the innominate artery, LCA, and LSA; (B and C) cross section of CTA showed that the tear involved the innominate artery, LCA, and LSA; (D) postoperative CTA presented possible access sites of 3 branches of fenestration and stent placement; (E and F) cross section of postoperative CTA showed that the in situ laser fenestrations of the 3 branches were patent. CTA indicates computed tomography angiography; LCA, left carotid artery; LSA, left subclavian artery; TEVAR, thoracic endovascular aortic repair.