Early results of transcatheter electrosurgical aortic septotomy for endovascular repair of chronic dissecting aortoiliac aneurysms.

Objective: Endovascular repair of chronic dissecting aortoiliac aneurysms is challenging given the rigid septum, compressed true lumen (TL), and target vessels frequently originating in the false lumen. We have used transcatheter electrosurgical aortic septotomy (TEAS) before stent graft implantation under intravascular ultrasound (IVUS) and fusion guidance. The purpose of this study is to assess the outcomes of TEAS during complex endovascular repair of dissecting aneurysms. Methods: From 2021 to 2023, 17 patients underwent TEAS. The primary end point was technical success, with secondary end points of proximal and distal seals, target vessel instability, aortic and iliac TL and cross-sectional area (CSA) expansion, and aortic-related death. During the procedure, the aortic septum is crossed through a pre-existing entry or via electrocautery-activated 0.018-in. Astato XS20 wire (Asahi-Intecc) under IVUS and fusion guidance. The penetrated wire is then snared in the false lumen and pulled through the ipsilateral femoral access. A 1-cm length of the middle of the Astato wire coating is kinked in a three-sided polygonal configuration, denuded the inner surface of the wire using a no. 15 blade, and positioned at the apex of the septum. Both ends of the Astato wire are insulated with 0.018-in. microcatheters, and the back end of the wire is denuded and connected to cautery. Gentle traction is applied to the wire, and short bursts of electrocautery cutting are applied at 60 to 80 W. Results: The technical success of the septotomy was 100%. No incidence of visceral or lower extremity malperfusion, vascular injury, or distal embolization occurred. Of the 17 patients, 4 underwent thoracic endovascular aneurysm repair, 2 underwent endovascular aortic repair, and 11 underwent fenestrated/branched endovascular aneurysm repair after septotomy. All target vessels were successfully stented. A distal landing zone seal with exclusion of the false lumen was achieved in 16 of the 17 patients (94.1%). One patient required embolization of the false lumen of the celiac artery after septotomy. The TL mean diameter and CSA of the descending thoracic aorta after septotomy was expanded by 7.01 ± 1.9 mm (relative mean diameter expansion, 42.3%; P < .0001) and 2.71 ± 0.4 cm2 (relative mean CSA expansion, 57.3%, P<.0001). For patients who required septotomy through the common iliac arteries, the mean TL was expanded by 8.1 ± 3.7 mm (relative mean diameter expansion, 76%; P < .0001) and 1.76 ± 0.91 cm2 (relative mean CSA expansion, 209%; P < .0001). The 1-year freedom from target vessel instability was 91%. Conclusions: The use of IVUS and fusion-guided TEAS offers a promising technique to facilitate TL expansion and false lumen exclusion in chronic dissecting aortic aneurysms before repair. The durability and long-term outcomes of this technique in a larger cohort remain to be elucidated.

Aortic septotomy to optimize landing zones during thoracic endovascular aortic repair for chronic type B aortic dissection.

OBJECTIVE: The role of thoracic endovascular aortic repair for chronic type B aortic dissection remains controversial. Clinical outcomes of thoracic endovascular aortic repair with recently implemented aortic septotomy strategy were compared with stand-alone thoracic endovascular aortic repair. METHODS: Between 2008 and 2020, 88 patients with chronic type B aortic dissection and degenerative aortic aneurysm underwent a thoracic endovascular aortic repair with or without adjunctive aortic septotomy, consisting of 36 (41%) with de novo chronic type B aortic dissection and 52 (59%) with residual chronic type B aortic dissection after type A aortic dissection repair. RESULTS: Aortic septotomy was performed in 31 patients (35%) to optimize the proximal (3/31;10%) and distal (31/31;100%) landing zones. The aortic septotomy techniques comprised laser aortic septotomy in 16 patients (52%) and cheese wire septotomy in 15 patients (48%) with a 97% overall technical success rate. The median time interval between aortic dissection occurrence and thoracic endovascular aortic repair was 1.2 years. During follow-up, there were 12 (21%) sudden deaths and 17 (30%) combined aorta-related and sudden deaths in the nonaortic septotomy group, whereas there were no deaths in the septotomy group (P < .001). Patients without aortic septotomy required aortic reinterventions more frequently than those with aortic septotomy (30% vs 7%; P = .014), and 77% of these procedures were related to residual retrograde false lumen flow. Positive aortic remodeling was confirmed in 90% and 37% in the aortic septotomy and nonseptotomy groups, respectively (P < .001). CONCLUSIONS: Stand-alone thoracic endovascular aortic repair outcomes without adjunctive procedures for chronic type B aortic dissection remain unfavorable. In contrast, landing zone optimization using aortic septotomy resulted in a remarkably higher positive aortic remodeling rate. Routine aortic septotomy strategy may positively affect long-term chronic type B aortic dissection survival and expand thoracic endovascular aortic repair candidacy.

Laser aortic septotomy during thoracic endovascular aortic repair for chronic type B aortic dissection.

OBJECTIVE: Persistent false lumen perfusion due to the presence of a thick aortic septum is a significant obstacle to successful thoracic endovascular aortic repair for chronic type B aortic dissection (cTBAD). We describe our new approach of laser aortic septotomy to optimize the landing zone. METHODS: Between 2019 and 2020, 11 patients with cTBAD with degenerative aneurysm underwent laser aortic septotomy during thoracic endovascular aortic repair. A prospectively maintained database was retrospectively reviewed. RESULTS: The median age was 70.0 years, and 10 (91%) were men. Six (55%) were de novo type B aortic dissection and 5 (45%) were residual type B aortic dissection. The age of aortic dissection was 2.9 years (interquartile range, 1.1-12.1). Technical success was achieved in 91% (10/11). In 1 case (9%), laser aortic septotomy was not feasible due to extremely tortuous aorta. Among successful cases, the median extents of proximal and distal laser fenestrations were Th7.5 and Th11.0, respectively and distal landing zones included zone 4 (40%) and zone 5 (60%). Two (18%) underwent a continuous longitudinal laser fenestration, and 8 (73%) had longitudinal spot laser fenestrations with immediate balloon dilatations. Apposition of the stent-graft to the outer aortic wall of the newly created common aortic lumen with elimination of retrograde false lumen flow was achieved in all cases. CONCLUSIONS: This is the first description using the laser technology to optimize the distal landing zone for cTBAD. This new technique is safe and reproducible, with excellent controllability to achieve aortic septotomy at the desired target aorta segment.