Transcatheter Electrosurgical Aortic Septotomy Across the Spectrum of Type B Aortic Dissection: Feasibility, Technical Lessons, and Bailout Strategies

Abstract

Introduction

Transcatheter electrosurgical aortic septotomy (TEAS) has been introduced to optimise luminal geometry during endovascular repair of complex type B aortic dissection (TBAD), but data across dissection phases and on complication management remain limited. This study reports early outcomes, quantitative common lumen creation, and bailout strategies from a consecutive single centre experience.

Method

Eight consecutive patients underwent TEAS, between December 2024 and January 2026, as an adjunct to thoracic endovascular aortic repair or physician modified fenestrated endograft for acute, subacute, or chronic TBAD, including post-type A repair and genetic aortopathy. Pre-procedural and follow up computed tomography angiography (CTA) quantified true lumen and common lumen cross sectional area. Septotomy technical success, peri-operative outcomes, complications, and early follow up were assessed.

Results

The mean age was 51.1 ± 17 years; five were men. Two patients were acute, two subacute, and four chronic; two had Marfan syndrome, both redo cases after previous open repair. Septotomy technical success was 100%. The median cross sectional area increased from 174.5 mm² (pre-procedural true lumen) to 1 007 mm² (follow up CTA common lumen) after TEAS (5.3 fold increase). There were no 30 day, in hospital, or aortic related deaths. Three major procedure related complications (38%) occurred, all in non-acute cases and all managed endovascularly: one iliac lamellar dislodgement requiring kissing stents, one external iliac rupture treated with stent grafting, and one delayed superior mesenteric artery occlusion managed with stenting. All acute cases were uneventful. Median clinical follow up was 32 days (range 22 – 308) and median imaging follow up was 20 days (range 2 – 265), with no late deaths, no aortic re-interventions, and no aneurysmal dilatation of the non-stented TEAS treated segment.

Conclusion

TEAS may be considered across acute, subacute, and chronic TBAD, including redo and connective tissue disease cases, enabling reproducible common lumen creation and landing zone optimisation. All complications were recognised and managed endovascularly and were observed only in non-acute dissections, although the sample size precluded meaningful assessment of any relationship between dissection phase and technical risk. These findings support TEAS as a feasible adjunct in carefully selected complex dissections, offer practical principles for safe adoption, and reflect an early experience that may be influenced by the learning curve of this technically demanding procedure.

HIGHLIGHTS

• •Transcatheter electrosurgical aortic septotomy was feasible across dissection phases
• •Technical success was achieved in all cases, with substantial true lumen gain
• •Complications related more to technical factors than dissection phase
• •Pre-emptive wiring and rescue access enabled effective complication bailout
• •All complications could be managed endovascularly without permanent sequelae

INTRODUCTION

Management of complex type B aortic dissection (TBAD) remains technically challenging, particularly with a severely compressed true lumen, visceral malperfusion, dissecting aneurysmal degeneration, or previous proximal aortic repair. Thoracic endovascular aortic repair (TEVAR) has become first line treatment for complicated TBAD;¹ however, successful stent graft deployment requires adequate proximal and distal landing zones and sufficient true lumen expansion to ensure device stability and branch vessel perfusion. In selected cases, persistent septal rigidity, unfavourable intimal flap orientation, or a previous frozen elephant trunk stent graft deployed into the false lumen (FL) may compromise definitive endovascular reconstruction.

Adjunctive strategies aimed at modifying the dissection septum have therefore been developed to improve luminal geometry and facilitate durable repair. Conventional wire based septotomy and balloon mediated intimal disruption techniques have been described,² yet these approaches may rely heavily on mechanical traction and can be difficult to control, particularly in acute dissections with fragile lamellae. Transcatheter electrosurgical aortic septotomy (TEAS) introduces controlled energy mediated division of the intimal flap, enabling creation of a common lumen while potentially reducing uncontrolled tearing.2, 3, 4, 5

Although TEAS has been reported in limited series,2, 3, 4, 5 its application across heterogeneous dissection phases, including acute, subacute, chronic, post-type A repair, and genetic aortopathy, remains incompletely characterised. Moreover, systematic descriptions of complication recognition and structured salvage strategies are sparse. Given the potential risks of lamellar dislodgement, branch vessel compromise, and access related rupture, detailed reporting of procedural safeguards is essential.

This retrospective study describes early single centre experience with TEAS as an adjunct to complex endovascular aortic repair across different phases of TBAD. It focuses on technical strategy, common lumen creation, and, importantly, intra-operative complication recognition and bailout management.

Study design

This retrospective study was conducted at a single tertiary referral centre using a prospectively maintained institutional database. All consecutive patients with complex type B aortic dissection, de novo TBAD, or residual or new type B dissection after previous type A repair, who underwent TEVAR or physician modified fenestrated endograft (PMEG) repair with adjunctive TEAS because conventional techniques were insufficient, between December 2024 and January 2026, were included. Demographic, procedure, and outcome data were collected retrospectively. The study was approved by the Institutional Review Board of National Taiwan University Hospital (IRB No. 202307217RNA), and written informed consent was obtained from all patients.

METHODS

Indications and contraindications

TEAS was performed as an adjunctive technique to optimise the aortic lumen and facilitate definitive endovascular repair, and was never used as a standalone procedure. Eligibility required at least one of the following indications: severe true lumen compression preventing adequate catheter manipulation or device deployment; creation of suitable landing zones when the dissection flap extended into planned sealing zones; target vessel incorporation when branch vessels originated from the FL, facilitating fenestrated endovascular repair; organ or limb malperfusion due to true lumen collapse. Malperfusion was defined by clinical symptoms and signs with supportive laboratory data, confirmed radiographically on concurrent computed tomography angiography (CTA).

Because TEAS is technically demanding, the following contraindications took precedence over the indications, and the procedure was not performed whenever any was present or suspected: haemodynamic instability; impending rupture; a thrombosed FL or extensive mural thrombus, often without a prominent distal fenestration; extensive calcification of the dissection flap; and unfavourable anatomy for endovascular access.

The decision to perform TEAS rather than TEVAR alone was made before the procedure on the CTA findings: a severely compressed true lumen producing a suboptimal endograft landing zone, typically in chronic dissection, or malperfusion, typically in acute dissection, prompted TEAS. Accordingly, most cases were chronic or subacute, and in acute complicated TBAD, TEAS was reserved for highly selected patients with clear malperfusion. Septotomy was followed by planned TEVAR or PMEG repair depending on anatomic requirements.

Endpoints

The primary endpoint was septotomy technical success, defined at the procedural level as successful electrosurgical division of the intimal flap to create a common lumen (common trunk) with deployment of all intended endograft components, thereby achieving the intended landing zone optimisation. Septotomy technical success was assessed independently of peri-procedural adverse events, which are reported separately as safety endpoints and were not classified as technical failures. Secondary endpoints included quantitative true lumen expansion, proximal and distal sealing integrity, and early and late clinical outcomes including overall and aortic related death. Major adverse events comprised lamellar dislodgement, visceral or lower extremity malperfusion, distal embolisation, and aortic or iliac rupture.

Statistical analysis

Given the small, single arm cohort, analyses were descriptive. Continuous variables are presented as median (interquartile range) or mean ± standard deviation, and categorical variables as counts and percentages. No formal hypothesis testing or comparative analysis was performed, given the sample size. Analyses were performed using IBM SPSS Statistics version 31 (IBM Corp., Armonk, NY, USA).

Transcatheter electrosurgical aortic septotomy technique and pre-procedure evaluation

Pre-operative thin slice CTA was analysed on a three dimensional workstation (3mensio, Pie Medical Imaging, Maastricht, the Netherlands) to define flap morphology and orientation, fenestration locations, true and FL dimensions, aneurysmal degeneration, the relationship between target vessels and the two lumens, and centreline lengths for access planning; these findings guided access side and the intended septotomy level. Procedures were performed in a hybrid operating room through bilateral common femoral access. Septotomy used a manually modified 0.014 inch Astato XS20 guidewire (Fig. 1), insulated with microcatheters and long sheaths and connected to an electrocautery generator in cutting mode at 70 W, with dual safety wires placed pre-emptively. Septotomy was extended from the most proximal available fenestration to the distal extent of the dissected segment, with the infrarenal abdominal aorta (zone 9) as the distal limit; it was confined to the aorta and was not extended into the iliac segment in any patient. Definitive repair used TEVAR or a PMEG, modified on the sterile back table immediately before implantation. Intravascular ultrasound was used before septotomy for fenestration creation and visceral ostium assessment, and routinely after septotomy before endograft deployment; completion angiography confirmed luminal expansion and branch patency. True and common lumen cross sectional areas were measured on the pre-operative and the latest available follow up CTA. The full technique is detailed in Supplementary Methods S1.

Figure 1.

Transcatheter electrosurgical aortic septotomy (TEAS) technique and device configuration. A 0.014 inch Astato XS20 guidewire with a denuded polygonal midportion was positioned across the intimal flap and insulated with CXI microcatheters and long sheaths, with additional safety and target vessel guidewires placed pre-emptively. Electrosurgical septotomy was performed by connecting the wire to an electrocautery generator and applying controlled traction under fluoroscopic guidance with dextrose insulation to create a common lumen.

RESULTS

Eight consecutive patients underwent TEAS assisted endovascular aortic repair (Table 1). The mean age was 51.1 ± 17.0 years (median 59 years; range 26 – 71), and five were men. Two presented in the acute phase with malperfusion (< 2 weeks), two in the subacute phase (two weeks to three months), and four in the chronic phase (> 3 months). Underlying pathology comprised de novo type B dissection and residual or new type B dissection after previous open repair of the ascending aorta and arch; two had Marfan syndrome, both redo cases after previous open repair.

Table 1.

Baseline characteristics and aortic anatomy (n = 8).

Variables
Demographics
Age – y	59 (34, 64)
Men	5 (63)
Hypertension	7 (88)
Dyslipidaemia	2 (25)
Diabetes mellitus	1 (13)
Active smoker	0 (0)
Coronary artery disease	1 (13)
Cerebrovascular disease	0 (0)
Chronic obstructive pulmonary disease	0 (0)
Genetic aortic disease	2 (25)
End stage renal disease on dialysis	0 (0)
Pre-operative creatinine – mg/dL	0.96 (0.81, 1.10)
ASA class III	6 (75)
ASA class IV	2 (25)
Aortic status
Acute type B dissection	2 (25)
Residual or new type B after previous type A repair	4 (50)
Chronic dissecting aneurysmal degeneration	2 (25)
Branch malperfusion at presentation	3 (38)
Primary entry location – TEM
E3	7 (88)
E0	1 (13)
Proximal dissection zone – Ishimaru
Zone 3	6 (75)
Zone 4	2 (25)
Distal dissection zone – Ishimaru
Zone 5	1 (13)
Zone 9	2 (25)
Zone 10	1 (13)
Zone 11	4 (50)

Data are presented as median (interquartile range) or n (%). ASA = American Society of Anesthesiologists; TEM = type, entry, malperfusion.

TEAS was successfully performed in all eight patients and was followed by definitive TEVAR or PMEG repair according to anatomic requirements. Septotomy technical success was achieved in all eight cases (100%); the three major adverse events (38%), each recognised and salvaged endovascularly, are reported separately below. Completion angiography demonstrated immediate establishment of a common lumen configuration with restoration of antegrade flow in all treated segments. Mean pre-procedure true lumen CSA was 269.0 ± 294.5 mm² (median 174.5 mm²), increasing to 1 020.8 ± 292.6 mm² (median 1 007.0 mm²) on follow up CTA after TEAS and deployment of the definitive endograft (TEVAR or PMEG; The Valiant Captivia thoracic stent graft system, Medtronic, Santa Rosa, CA, USA), selected according to the proximal sealing zone) (median 5.26 fold increase; IQR 3.65, 9.42) (Table 2).

Table 2.

Procedure characteristics and common lumen creation.

Variable
Operating time – min	258.5 (224, 298)
Septotomy technical success	8 (100)
Proximal TEVAR landing zone
Zone 2	2 (25)
Zone 3	4 (50)
Zone 4	2 (25)
Physician modified fenestrated endograft	3 (38)
Visceral target vessel cannulation
Cannulation performed	3 (38)
Successful cannulation∗	3 (100)
Common lumen creation after septotomy
Pre-TEAS true lumen diameter – mm	8.25 (5.18, 12.75)
Post-TEAS common trunk diameter – mm	35.3 (30.03, 38.20)
Diameter fold increase	4.06 (2.51, 6.96)
Pre-TEAS true lumen CSA, mm2	174.5 (98.3, 276.8)
Post-TEAS common lumen CSA, mm2	1 007.0 (888.3, 1169.3)
CSA fold increase	5.26 (3.65, 9.42)

Values are median (interquartile range) or n (%). TEAS = transcatheter electrosurgical aortic septotomy; TEVAR = thoracic endovascular aortic repair; CSA = cross sectional area.

^∗Percentage calculated among cases in which cannulation was attempted.

There was no 30 day or in hospital death, no cerebrovascular event, myocardial infarction, and no post-operative respiratory failure. Three major procedure related complications were recorded, all in non-acute cases, and each was recognised and managed endovascularly. In one patient with chronic type B dissection, lamellar dislodgement with intimal invagination caused left common iliac artery occlusion and was treated with bilateral kissing iliac stent grafts. In one patient with chronic type A related residual dissection and Marfan syndrome, rupture of the left external iliac artery occurred during septotomy with transient haemodynamic collapse and was managed by emergency stent graft placement, with uneventful recovery. In one patient with subacute type B dissection, delayed superior mesenteric artery occlusion due to intimal flap invagination was identified on post-operative day one and was successfully treated by endovascular stenting (Table 3). Both acute cases, each presenting with branch malperfusion, were completed without a major complication. All three patients with malperfusion had static malperfusion, classified according to the 2024 ESC guidelines.⁶ None of the three major complications occurred in these patients, and pre-operative malperfusion type was therefore not associated with the observed complications in this series.

Table 3.

Early and follow up outcomes.

Variable
30 day death	0 (0)
In hospital death	0 (0)
TEAS related major adverse events∗	3 (38)
Stroke	0 (0)
Myocardial infarction	0 (0)
Respiratory failure	0 (0)
Acute kidney injury	0 (0)
Temporary paraplegia	0 (0)
Permanent paraplegia	0 (0)
Endoleak	0 (0)
ICU stay – d	1.5 (1.0, 5.25)
Hospital length of stay – d	8 (3.75, 11.75)
Follow up duration – d	32 (23, 104)
Survival at last follow up	8 (100)
Late aortic re-intervention	0 (0)

Values are presented as median (interquartile range) or n (%). TEAS = transcatheter electrosurgical aortic septotomy. ICU = intensive care unit.

^∗Defined as transcatheter electrosurgical aortic septotomy related procedure complications, including intimal lamellar dislodgment, visceral artery compromise, distal embolisation, and aortic or iliac artery rupture.

Clinical follow up was available in all eight patients (median 32 days, range 22 – 308 days). Imaging follow up, defined as the interval from the procedure to the latest available CTA, was a median of 20 days (range 2 – 265 days); per patient intervals are given in Supplementary Table S1. There were no late deaths, no aortic related deaths, and no aortic re-interventions during this interval. All remained alive with preserved branch patency and satisfactory early aortic remodelling on follow up imaging (Table 3). The change in total aortic cross sectional area at four levels (descending thoracic aorta, diaphragm, renal artery level, and infrarenal aorta) is provided in Supplementary Table S1. No aneurysmal dilatation of the non-stented TEAS treated segment was observed. This interval reflects early post-procedural imaging only and is insufficient to establish mid- or long term stability of the unstented septotomised segment; CTA surveillance is ongoing and longer follow up will be required before any durability claim can be made. The FL within the endograft covered segment was completely (100%) thrombosed in all patients.

DISCUSSION

It is believed that this study represents an early Asian experience with TEAS and one of the few reports to describe complication recognition and bailout management in a mechanism based way. Optimisation of landing zones has previously been described using conventional wire based septotomy techniques.⁷ TEAS, which employs high energy electrocautery to vaporise the intimal flap, may offer a more controlled and reproducible method of septal division. Consistent with previous reports,2, 3, 4, 5 the resulting common lumen enhances landing zone quality for endograft deployment. It has also been used as a rescue strategy when the distal portion of a frozen elephant trunk graft is inadvertently deployed into the FL.

In chronic TBAD aneurysm with FL degeneration, TEVAR by proximal tear coverage alone achieves complete FL thrombosis in 55 – 88% of patients,⁸ with persistent distal fenestrations causing ongoing FL perfusion and progressive aneurysmal dilatation.⁹ Adjunctive strategies such as embolisation, and the candy plug and Knickerbocker techniques have been used, but TEAS recreates a unified lumen before stent grafting, potentially reducing persistent FL perfusion and endoleaks.⁹ Rapid FL thrombosis was observed within 48 hours after TEAS with TEVAR; larger studies are needed to determine durability.

The rationale for this standardised common trunk strategy is that equalisation of true and false lumen pressures after septotomy may promote positive aortic remodelling. This concept is supported by Fukuhara et al.,¹⁰ who reported that landing zone optimisation using aortic septotomy produced a markedly higher rate of positive aortic remodelling and may improve long term outcomes and expand TEVAR candidacy in chronic type B dissection, and it is conceptually analogous to open distal fenestration during elephant trunk repair, which promotes positive remodelling with aneurysm sac regression and eliminates retrograde FL flow.¹¹ Because the TEAS treated aortic segment distal to the endograft is left without stent coverage, the current authors routinely follow this segment for aneurysmal dilatation and would undertake aortic re-intervention if indicated; on current early follow up of all eight patients, there has been no such dilatation. These early findings, complete (100%) FL thrombosis within the endograft covered segment and stability of the non-stented common trunk segment, are consistent with this concept, although longer follow up is needed.

Common lumen creation may reduce excessive distal oversizing in acute TBAD with a severely compressed true lumen, potentially lowering the risk of distal stent graft induced new entry.¹ Although TEVAR remains first line for acute TBAD, it may not adequately resolve dynamic visceral malperfusion in selected patients. Adjunctive strategies, including fenestration, PETTICOAT, and STABILISE, have been introduced, but their long term durability remains under investigation. The PETTICOAT technique deploys a distal bare metal stent to scaffold and expand the true lumen while leaving the dissection septum intact; it can relieve dynamic malperfusion but does not obliterate the septum, and branches arising from the FL remain difficult to incorporate. The STABILISE modification adds balloon assisted rupture of the septum to approximate a single lumen but relies on uncontrolled mechanical tearing. From the current authors’ view, the principal advantages of TEAS are twofold: it creates a true common trunk permitting incorporation of all aortic branches, including those originating from the FL — a capability that PETTICOAT and STABILISE do not reliably provide; and electrocautery enables more precise and controllable flap division than mechanical tearing of a traditional cheese wire or balloon rupture technique. In the absence of a comparative cohort, eight patients cannot support conclusions about comparative safety or long term durability, and therefore these distinctions are presented as conceptual; comparative studies are needed to define the relative roles of these techniques. A primary concern with TEAS in the acute phase is flap fragility, as excessive traction may cause uncontrolled lamellar disruption.⁹ In the current two acute cases, strict adherence to energy controlled septotomy under gentle traction enabled successful septotomy without complication (Video 1).¹⁰ While two patients cannot establish safety, this experience suggests that the acute phase need not preclude TEAS.

Supplementary video related to this article can be found at https://doi.org/10.1016/j.ejvsvf.2026.09.003

The following is/are the supplementary data related to this article:

Video 1

Transcatheter electrosurgical aortic septotomy (TEAS) in acute type B aortic dissection with malperfusion, demonstrating through and through wire creation, controlled electrosurgical septotomy, and subsequent thoracic endograft deployment with restoration of visceral perfusion.

On review, the determinants of the complications appeared to relate more to controllable technical and anatomic factors, energy transfer, wire management, and pre-identifiable flap anatomy, than to the dissection phase: all three occurred in non-acute cases (two chronic, one subacute), while both acute cases were uneventful. This observation should be interpreted with caution given the small sample size, which included only two acute cases, and is offered to inform safer technique rather than as a definitive association.

Firstly, lamellar dislodgement remains a significant risk. In one patient with a chronic type B dissection, lamellar dislodgement after TEAS led to left common iliac artery occlusion (Fig. 2A–C). Retrospective fluoroscopic review suggested suboptimal contact between the exposed conductive surface of the wire and the intimal flap, resulting in insufficient energy mediated vaporisation and increased reliance on mechanical traction. Bilateral common iliac kissing stent grafts were successfully deployed to restore limb perfusion. This case strengthens the idea that inadequate energy transfer, rather than flap fragility, may precipitate lamellar displacement. Proper insulation, controlled power delivery, and meticulous wire–flap alignment are therefore essential.¹⁰

Figure 2.

Endovascular salvage of three transcatheter electrosurgical aortic septotomy (TEAS) complications. Row 1 lamellar dislodgment after TEAS requiring iliac kissing stent grafts: (A) poor contact between exposed wire and intimal flap (arrow); (B) infrarenal aortic occlusion (arrowheads); (C) post-operative computed tomography angiography (CTA) showing restored bilateral iliac perfusion after kissing stent grafts. Row 2 left external iliac artery rupture during TEAS with endovascular salvage: (D) contralateral pigtail catheter (arrowheads) entangled with the TEAS wire; (E) iliac rupture (arrow); (F) emergency stent graft placement. Row 3 delayed superior mesenteric artery (SMA) compromise from flap invagination after TEAS: (G) pre-procedural CTA showing flap hinge point at the SMA ostium; (H) delayed flap invagination with luminal compromise on POD1; (I) angiography confirming SMA ostial obstruction (arrow); (J) restored SMA patency after stenting.

Secondly, aortic or iliac rupture represents the most catastrophic potential complication. In one patient with chronic, type A related residual dissection and Marfan syndrome, rupture of the left external iliac artery occurred during septotomy via left femoral access. Wire entanglement between the contralateral pigtail catheter and the through and through Astato wire probably generated torsion, resulting in unintended contact between the energised denuded segment and the vessel wall (Fig. 2D–F). The patient developed peri-procedural haemorrhagic shock; emergency stent graft deployment in the external iliac artery successfully achieved haemostasis, and the patient was ultimately discharged without neurological deficit. This event is fundamentally a wire management problem, independent of dissection phase, and underscores the critical importance of meticulous wire management and strict control of energy delivery.

Thirdly, delayed intimal flap invagination into visceral branches represents a particularly insidious complication, as it may not be immediately evident intra-operatively. In one patient with a subacute type B dissection, visceral perfusion appeared satisfactory following TEAS and TEVAR; however, on post-operative day one, the patient developed abdominal discomfort. Imaging revealed superior mesenteric artery (SMA) ostial occlusion due to flap invagination (Fig. 2G–J). Emergency endovascular SMA intervention with bare metal stent placement successfully restored flow. In this case, the flap hinge lay at the SMA ostium, an anatomic feature identifiable on pre-procedural imaging, and this case illustrates that post-septotomy flap dynamics may evolve and are not always predictable at the time of intervention.

No reliable predictive model exists for post-TEAS intimal flap orientation relative to visceral branch ostia. The authors considered target vessels at high risk when the flap hinge lay at or adjacent to the branch ostium. A 0.018 inch guidewire was then advanced prophylactically before septotomy, with bare metal stenting where intravascular ultrasound suggested substantial invagination risk.

In this early learning experience, three of eight patients (38%) sustained a major procedure related complications. All were recognised and salvaged endovascularly, with no peri-operative or aortic related death. This rate is numerically higher than in the largest electrosurgical septotomy series: Ruiter Kanamori et al.³ (n = 36) reported 92% technical success and an 8% 30 day major adverse event rate, and Figueroa et al.² (n = 20) reported 100% septotomy technical success with a single (5%) septotomy related event, a difference that partly reflects the small denominator, in which each single event represents 12.5%. On retrospective review, all three complications were considered to have been avoidable through technical refinement.

Finally, the application of TEAS in genetic aortopathy remains controversial. Endograft use in connective tissue disorders is generally discouraged due to concerns about long term durability, and open repair remains preferred in suitable candidates.¹ Nevertheless, endovascular intervention may be justified in high risk patients, life threatening acute presentations, or redo scenarios. Both Marfan syndrome patients in this series had undergone previous open aortic repair, and one presented acutely with visceral and limb malperfusion. The authors regard TEAS in this context as a salvage or bridging adjunct for highly selected patients under lifelong surveillance. A long term study is planned to further evaluate the durability, safety, and clinical impact of TEAS in this patient population.

Limitations

These findings should be interpreted within the scope of an early clinical experience. The cohort was small and spanned diverse dissection phases and aetiologies, and the absence of a comparator reflects the novelty of the technique; the results are therefore evidence of feasibility rather than comparative superiority and require validation in larger cohorts. The limited sample size, including only two acute cases, precluded meaningful assessment of the relationship between dissection phase and technical risk, and this observation is hypothesis generating rather than evidence of causality. Follow up remained early, and the durability of these results—particularly in connective tissue disease, requires continued surveillance. Imaging follow up was short (median 20 days, range 2 – 265 days), so these data reflect early post-procedural imaging only and cannot establish mid- or long term stability of the unstented septotomised segment; CTA surveillance of that segment is ongoing.

Conclusion

In this early single centre experience, TEAS was completed in all eight patients across acute, subacute, and chronic type B aortic dissection, achieving consistent septotomy technical success and substantial common lumen creation in complex endovascular repair. Three major complications (38%) occurred, all in non-acute cases; each was recognised and managed endovascularly, with no peri-operative or aortic related death and no aortic re-intervention on early follow up. On review, these events appeared to relate more to technical execution, energy transfer and wire management, and to pre-identifiable flap anatomy than to dissection acuity, and were mitigated by pre-defined safety measures including pre-emptive visceral wiring and rescue access preparation. This experience supports TEAS as a feasible adjunct in carefully selected complex dissections, potentially including acute presentations and highly selected redo or high risk connective tissue disease patients, when conventional strategies are insufficient and a structured bailout plan is in place. These findings reflect an early clinical experience with TEAS, and procedural outcomes may be influenced by the learning curve associated with this technically demanding procedure. Long term durability, particularly in connective tissue disease, remains the principal unanswered question and will require validation in larger studies with longer follow up.

DECLARATION OF GENERATIVE AI AND AI ASSISTED TECHNOLOGIES IN THE MANUSCRIPT PREPARATION PROCESS

During the preparation of this work, the authors used Claude solely to correct grammar and spelling. The authors then reviewed and edited the content as needed and take full responsibility for the published article.

CONFLICTS OF INTEREST AND FUNDING

None.

Appendix A. Supplementary data

The following is/are the supplementary data to this article: