"Powered Cheese Wire Technique" for Septal Fenestration in Complex Endovascular Repair for Chronic Thoracoabdominal Aortic Dissection

Indications, safety, and effectiveness of transcatheter electrosurgical septotomy during endovascular repair of aortic dissections

OBJECTIVE

Endovascular repair of aortic dissections may be complicated by inadequate sealing zones, persistent false lumen perfusion, and limited space for catheter manipulation and target artery incorporation. The aim of this study was to describe the indications, technical success, and early outcomes of transcatheter electrosurgical septotomy (TES) during endovascular repair of aortic dissections.

METHODS

We reviewed the clinical data of consecutive patients treated by endovascular repair of aortic dissections with adjunctive TES in two centers between 2021 and 2023. End points were technical success, defined by successful septotomy without dislodgment of the lamella or target artery occlusion, and 30-day rates of major adverse events (MAEs).

RESULTS

Among 197 patients treated by endovascular repair for aortic dissections, 36 patients (18%) (median age, 61.5 years (interquartile range, 55.0-72.5 years; 83% male) underwent adjunctive TES for acute (n = 3 [8%]), subacute (n = 1 [3%]), or chronic postdissection aneurysms (n = 32 [89%]). Indications for TES were severe true lumen (TL) compression (≤16 mm) in 28 patients (78%), target vessel origin from false lumen in 19 (53%), creation of suitable landing zone in 12 (33%), and organ/limb malperfusion in four (11%). Endovascular repair included fenestrated-branched endovascular aortic repair (EVAR) in 18 patients (50%), thoracic EVAR/EVAR/PETTICOAT in 11 (31%), and arch branch repair in 7 (19%). All patients had dissections extending through zones 5 to 7, and 28 patients (78%) underwent TES across the renal-mesenteric segment. Technical success of TES was 92% (33/36) for all patients and 97% (32/33) among those with subacute or chronic postdissection aneurysms. There were three technical failures, including two patients with acute dissections with inadvertent superior mesenteric artery dissection in one patient and distal dislodgement of the dissection lamella in two patients. There were no arterial disruptions. The mean postseptotomy aortic lumen increased from 13.2 ± 4.8 mm to 28.4 ± 6.8 mm (P < .001). All 18 patients treated by fenestrated-branched EVAR had successful incorporation of 78 target arteries. There was one early death (3%) from stroke, and three patients (8%) had major adverse events. After a median follow-up of 8 months (interquartile range, 4.5-13.5 months), 13 patients (36%) had secondary interventions, and two (6%) died from non-aortic-related events. There were no other complications associated with TES.

CONCLUSIONS

TES is an adjunctive technique that may optimize sealing zones and luminal aortic diameter during endovascular repair of subacute and chronic postdissection. Although no arterial disruptions or target vessel loss occurred, patients with acute dissections are prone to technical failures related to dislodgement of the lamella.

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.

The Electrified Wire Technique in Complex Aortic Interventions: A Case Series

OBJECTIVES

Electrosurgery has been long used in endovascular procedures, with only case reports in the aortic field. Our aim is to present a case series with the use of an electrified wire to perform catheter-based electrosurgery by applying external current through an electrocautery pen.

METHODS

Single-center retrospective case series of all patients undergoing complex aortic surgery from October 2020 to August 2023, in whom the electrified wire technique was used: (1) Perforation of a dissection flap or left subclavian artery (LSA) in situ endograft fenestration-a 0.014" polytetrafluoroethylene (PTFE) insulated guidewire is detached from the insulation with a scalpel at the end and a cautery pen is here attached with a clamp. A curved tip catheter or sheath is positioned against the aortic flap or the endograft (through a left brachial access in this case) and the wire pushed, crossing the flap by activating the electrocautery pen and (2) slicing a dissection flap ("powered cheese-wire technique")-after same preparation as above, the middle section of the 0.014 guidewire is removed from the PTFE and bent into a V-shape. Once in the aorta, the guidewire crosses from the true lumen (TL) to the false lumen (FL) and a through-and-through access is obtained. Sheaths are positioned against the flap from both sides and moved up or down while the electricity is activated, slicing the flap and communicating both lumens. Technical success and technical-related complications were evaluated.

RESULTS

Eleven cases concerning aortic dissections and 1 case of aortic atresia were treated. Four patients presented urgently, whereas the rest were planned procedures. Seven cases underwent perforation of a dissection flap, 2 cases underwent the powered cheese-wire technique, in 2 cases for an LSA in situ fenestration, and in 1 case to cross an aortic atresia at the aortic isthmus. The technique was in all cases successfully applied. No complications related to the technique occurred.

CONCLUSIONS

The "electrified wire" technique is a feasible and ready-available tool that can be safely used in complex aortic interventions, especially to perforate aortic tissue like dissection flaps or to perform in situ fenestrated repairs by perforation of the endograft fabric.

CLINICAL IMPACT

The electrified wire technique described herein is a straightforward technique that uses readily available tools to perform electrosurgery. We present its use in complex aortic procedures. However, it could be envisioned for any vascular procedure that requires crossing of the vessel or even prosthetic material. As we have described in this series, when used along with an adequate properative planning, it can be a safe tool of great utility, as has already been demonstarted in the field of the interventional cardiology.

Transcatheter electrosurgical septotomy technique for chronic postdissection aortic aneurysms

Aortic dissection often results in chronic aneurysmal degeneration due to progressive false lumen expansion. Thoracic endovascular aortic repair and other techniques of vessel incorporation such as fenestrated-branched or parallel grafts have been increasingly used to treat chronic postdissection aneurysms. True lumen compression or a vessel origin from the false lumen can present considerable technical challenges. In these cases, the limited true lumen space can result in inadequate stent graft expansion or restrict the ability to reposition the device or manipulate catheters. Reentrance techniques can be used selectively to assist with target vessel catheterization. Transcatheter electrosurgical septotomy is a novel technique that has evolved from the cardiology experience with transseptal or transcatheter aortic valve procedures. This technique has been applied in select patients with chronic dissection to create a proximal or distal landing zone, disrupt the septum in patients with an excessively compressed true lumen, or connect the true and false lumen in patients with vessels that have separate origins. In the present report, we summarize the indications and technical pitfalls of transcatheter electrosurgical septotomy in patients treated by endovascular repair for chronic postdissection aortic aneurysms.