Distal landing zone optimization before endovascular repair of aortic dissection

Visceral Aorta Electrocautery Septotomy to Allow Branched Endovascular Aortic Repair in Ruptured Chronic Post-Dissection Thoraco-Abdominal Aneurysm

PURPOSE

Endovascular repair of chronic post-dissection thoraco-abdominal aortic aneurysms (PD-TAAA) presents specific technical challenges due to the presence of chronic septum. Small true lumen diameter and false lumen visceral vessel origin can make branched endograft prohibitive. Septotomy may allow to overcome these challenges in cases of high complex anatomy.

TECHNIQUE

We describe the application of electrocautery septotomy to the visceral aorta segment to deploy an off-the-shelf branched endograft in a chronic PD-TAAA rupture with true lumen collapse.

CONCLUSIONS

Electrocautery septotomy can be an effective adjunctive technique to facilitate branched endograft, overcoming technical challenges associated with the endovascular treatment of chronic PD-TAAA.

CLINICAL IMPACT

Electrocautery septotomy is an adjunctive technique that can facilitate endovascular treatment of post-dissection thoraco-abdominal aneurysm. By creating a common lumen, this technique might reduce the number of re-interventions associated with PD-TAAA endovascular exclusion.

Novel Technique to Fenestrate an Aortic Dissection Flap using Electrocautery

Chronic distal thoracic dissections treated with thoracic endovascular repair are prone to type Ib false lumen perfusion. When the supraceliac aorta is of normal caliber, fenestration of the dissection flap proximal to the visceral vessels creates a seal zone for the thoracic stent graft and eliminates the type Ib false lumen perfusion. We describe a novel way of crossing the septum using electrocautery delivered through a wire tip then fenestrating the septum using electrocautery delivered over a 1-mm area of uninsulated wire to cut the septum. We believe the use of electrocautery creates a controlled and deliberate aortic fenestration during endovascular repair of a distal thoracic dissections.

Distal aortic replacement followed by endovascular repair for the management of severe intra-pleural adhesions accidentally detected during open surgery for chronic type B aortic dissection: a report of two cases

BACKGROUND

Open repair is the most promising curative treatment option for patients with chronic type B aortic dissection. However, based on our experience, following the accidental detection of intra-pleural adhesions during open surgery for chronic type B aortic dissection, complete replacement of the diseased aorta cannot be accomplished. To overcome this problem, we switched the procedure to create a distal landing zone for subsequent endovascular repair by replacing the distal aorta with a vascular graft.

CASE PRESENTATION

We report two cases in which open repair was attempted; however, the proximal descending thoracic aorta could not be exposed due to the presence of severe adhesion in the pleural cavity. In these patients, we accessed the lower descending thoracic aorta or thoracoabdominal aorta and created a distal landing zone for subsequent endovascular repair by replacing the aorta with a vascular graft. Thereafter, endovascular repair was performed with good outcomes.

CONCLUSIONS

Replacement of the distal aorta, which is typically easy to access despite the presence of intra-pleural adhesions, with a vascular graft serves as a reliable distal landing zone for subsequent endovascular repair. This method may be a viable option for the management of severe adhesions accidentally detected in the pleural cavity during open repair for chronic type B aortic dissection.

Thoracic Endovascular Aortic Repair for Chronic Type B Aortic Dissection: Pre- and Postprocedural Imaging

Aortic dissection is a chronic disease that requires lifelong clinical and imaging surveillance, long after the acute event. Imaging has an important role in prognosis, timing of repair, device sizing, and monitoring for complications, especially in the endovascular therapy era. Important anatomic features at preprocedural imaging include the location of the primary intimal tear and aortic zonal and branch vessel involvement, which influence the treatment strategy. Challenges of repair in the chronic phase include a small true lumen in conjunction with a stiff intimal flap, complex anatomy, and retrograde perfusion from distal reentry tears. The role of thoracic endovascular aortic repair (TEVAR) remains controversial for treatment of chronic aortic dissection. Standard TEVAR is aimed at excluding the primary intimal tear to decrease false lumen perfusion, induce false lumen thrombosis, promote aortic remodeling, and prevent aortic growth. In addition to covering the primary intimal tear with an endograft, several adjunctive techniques have been developed to mitigate retrograde false lumen perfusion. These techniques are broadly categorized into false lumen obliteration and landing zone optimization strategies, such as the provisional extension to induce complete attachment (PETTICOAT), false lumen embolization, cheese-wire fenestration, and knickerbocker techniques. Familiarity with these techniques is important to recognize expected changes and complications at postintervention imaging. The authors detail imaging options, provide examples of simple and complex endovascular repairs of aortic dissections, and highlight complications that can be associated with various techniques. Online supplemental material is available for this article. ^©RSNA, 2022.

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.

Staged Hybrid Single Lumen Reconstruction (TIGER) in Management of Chronic Symptomatic Complex Type B Aortic Dissection, Techniques, and Literature Review

BACKGROUND

Endovascular intervention for chronic symptomatic type B aortic dissection (CS-TBAD) induces aortic wall stress with negative hemodynamic cardiovascular consequences. CS-TBAD risks increased morbidity and mortality due to septum maturation with significant impact on false lumen modulation, and partial lumen thrombosis conveying the worst outcome. The aim of the TIGER technique is total aortic remodeling with true lumen expansion, false lumen regression and complete thrombosis, and stabilization of overall aortic diameter.

METHODS

We report 5 cases of aortic dissection with a mean follow-up of 16 months (6-28 months). All had aneurysmal dilation, with 3 having acute pan aortic dissection and 2 having CS-TBAD. All were managed by sTaged HybrId sinGle lumEn Reconstruction (TIGER). Our first approach was to create one single lumen from the supraceliac, infradiaphragmatic aorta to both common iliac arteries with open surgical patching of the visceral arteries; then, we performed a TEVAR 3 months later.

RESULTS

Three patients required a left subclavian artery chimney graft and one required bilateral subclavian to carotid artery transposition. No spinal drainage was required, and all patients had intraoperative transesophageal echo for wire guidance. We had no aortic rupture or retrograde type A dissection, and we experienced no renal, visceral, cardiac, pulmonary, or spinal complications. All patients, but one, went off their antihypertensive medication. All patients had normal estimated glomerular filtration rate postoperatively, and they all demonstrated accelerated aortic modulation.

CONCLUSIONS

TIGER was not only effective at the semiacute stage to initiate remodeling and prevent malperfusion, it also facilitated a straightforward TEVAR at stage 2, which was made easier by avoiding visceral branch stenting. Moreover, it decreased the length of aortic segment, which was stented, thereby avoiding critical shattering, branch dislodgment, and visceral compromise; spinal ischemia; and negative cardiovascular consequences.

Surgical Outcomes And Postoperative Descending Aorta Morphologic Remodeling After Thoracic Endovascular Aortic Repair For Acute And Chronic Type B Aortic Dissection

Background

This study aims to investigate the descending aortic morphological alterations caused by pathological changes in acute and chronic Type B aortic dissection (TBAD) and morphological remodeling after thoracic endovascular aortic repair (TEVAR).

Patients and methods

From February 2012 to January 2016, 86 TBAD patients undergoing TEVAR were divided into an acute group (n=63) and a chronic group (n=23). The areas of the true, false and maximal lumen and descending aorta morphological parameters, including the taper ratio (TR), oversizing ratio (OR), mismatch ratio (MR), radius of curvature (RoC) and tortuosity index (TI), were evaluated. Follow-ups were performed postoperatively before discharge, at 1 and 6 months, and yearly thereafter.

Results

Before TEVAR, the TR (0.57 (0.49) vs 0.74 (0.60); P < 0.05), OR (2.75 ± 1.89 vs 3.96 ± 2.27; P < 0.05) and TI (1.22 (1.19) vs 1.41 ± 0.17; P < 0.05) were significantly higher in the chronic group than in the acute group. The TEVAR technical success rate was 100%. No differences were found in 30-day and >30-day mortality between the two groups. Pathology-specific devices, such as tapered stent grafts and distal bare stents, were used more frequently in the chronic group than in the acute group (47.8% vs 23.8%, P = 0.03; 43.5% vs 12.7%, P = 0.002, respectively). The OR and TI changes that occurred after TEVAR were significantly higher in the chronic group than in the acute group (1.80 ± 0.86 vs 2.98 ± 1.85, P = 0.028; 0.00 ± 0.09 vs 0.09 ± 0.10, P < 0.001, respectively).

Conclusion

TEVAR is a safe and effective therapy for acute and chronic TBAD. Compared to acute TBAD, chronic TBAD resulted in an adverse preoperative descending aorta morphology. Pathology-specific devices may be a feasible treatment option for endovascular repair of chronic TBAD. A larger series of cases with longer follow-up are needed to draw definitive conclusions.

Proposed classification of endoleaks after endovascular treatment of Stanford type-B aortic dissections

Objectives

Despite two decades of experience, no dedicated classification system exists to document and prognosticate patterns of endoleak encountered after endovascular therapy of type-B aortic dissection. This nomenclature gap has led to inconsistent management and underreporting of significant findings associated with adverse outcomes after endovascular treatment of type-B aortic dissection. Our goal was to propose a reproducible and prognostically relevant classification.

Methods

A multidisciplinary team of seven experienced open and endovascular aortic surgeons was assembled to provide consensus opinion. Extensive literature review was conducted. Deficiencies in the current classification approach of the various patterns of persistent filling of false lumen after endovascular therapy were identified.

Results

Our focus was to categorize high-risk and low-risk subgroups within endoleaks after endovascular treatment of type-B aortic dissection. In this classification, type-Ia endoleak refers to persistent filling of the false lumen in an antegrade manner. Causes include failure to cover the primary entry tear and sizing or technical related proximal seal failure. False lumen filling via distal entry tears is classified as type Ib endoleak, which is further sub-classified into b1 (major branch-related tears), and b2 (multiple small branches related tears). Retrograde ascending aortic dissection and stent graft-induced new entry were classified as type-I endoleaks (type-Ir and type-Is, respectively). Another focus was reclassification type-II endoleaks, with type-IIa endoleak referring to conventional retroleak from one or more posterior branches and type-IIx referring to retroleak from major branches (visceral or left subclavian arteries).

Conclusions

The majority of endoleaks after endovascular treatment of type-B aortic dissection are related to persistent or new filling of the false lumen. We propose a new false lumen-based classification schema for endoleaks occurring after endovascular therapy of type-B aortic dissection.