Addressing Persistent False Lumen Flow in Chronic Aortic Dissection: The Knickerbocker Technique

Staged hybrid approach for acute type A aortic dissection: zone 2 arch replacement and completion thoracic endovascular aortic repair upon indication

OBJECTIVES

This study evaluates a staged selective hybrid approach for acute type A aortic dissection. The approach involves a zone 2 aortic arch replacement with debranching of the brachiocephalic trunk and left common carotid artery to create a landing zone for thoracic endovascular aortic repair. This repair is performed either pre-emptively in the subacute phase to promote remodelling or electively in the chronic phase to manage aneurysm formation.

METHODS

Between January 2022 and December 2023, data from patients undergoing this approach were prospectively collected and retrospectively analyzed. The study included all patients treated with zone 2 arch replacement and debranching for acute type A aortic dissection. Preoperative characteristics, surgical outcomes and follow-up interventions, including thoracic endovascular aortic repair, were assessed.

RESULTS

Of the 91 patients treated for acute type A aortic dissection, 25 underwent zone 2 arch replacement. No perioperative stroke or mortality occurred in this group (mean age 62.7 years, 52% male). Eleven patients (44%) underwent thoracic endovascular aortic repair during follow-up (median interval 152 days, range 38-574). Seven repairs were performed within 6 months of the initial operation. All procedures were technically successful without complications. Early imaging showed stable or reduced aortic diameters in all thoracic endovascular aortic repair patients. In the 14 patients managed conservatively, no relevant aortic growth was observed.

CONCLUSIONS

Zone 2 aortic arch replacement with debranching in acute type A aortic dissection can be performed safely. Selective pre-emptive thoracic endovascular aortic repair promoted favourable remodelling, potentially reducing the need for complex, open surgical reinterventions.

Questions and Certainty in Diagnosis and Management of Acute Type B Aortic Dissection

Type B aortic dissection (TBAD) is a severe cardiovascular condition that requires timely diagnosis and intervention to prevent life-threatening complications. The aim of this review was to focus on the most crucial and controversial aspects of contemporary TBAD management. It is recognized that in the acute phase, computed tomography angiography (CTA) plays an essential role in evaluating the extent of the dissection and monitoring disease progression. CTA has significantly improved the management of TBAD by providing detailed assessments of aortic anatomy and dynamic flow changes, positioning it as the cornerstone imaging modality for identifying acute high-risk patients who may require early intervention. Recently, new advances in magnetic resonance imaging (MRI) and positron emission tomography (PET) technology have the potential to provide further information beyond imaging alone. However, such sophisticated techniques should be reserved for stable patients after the acute phase. After decades of medical therapy and high risk surgery, thoracic endovascular aortic repair (TEVAR) has emerged as a minimally invasive alternative to open surgery for complicated TBAD, offering lower perioperative morbidity and mortality. Nevertheless, its use in uncomplicated TBAD remains a topic of ongoing debate. While recent studies suggest that preemptive TEVAR combined with optimal medical therapy may reduce late adverse events and improve long-term outcomes, these findings remain controversial. This review critically analyzes the current literature on both diagnosis and TEVAR treatment, evaluating these controversies in the context of clinical practice.

Staged, hybrid approach by zone 2 arch replacement and completion thoracic endoprosthesis in retrograde acute type A aortic dissection

We describe a case of retrograde acute type A aortic dissection approached by a hybrid, staged approach consisting of a zone 2 arch replacement and completion thoracic endovascular aortic repair procedure combined with distal balloon-assisted stent graft dilatation to prevent retrograde false lumen flow. This technique may be an alternative and more complete when compared with a frozen elephant trunk procedure at onset. Additionally, favorable remodeling of the entire thoracic aorta is observed.

Midterm Results of the STABILISE Technique in the Treatment of Aortic Dissection

Background: Contemporary treatments of acute aortic dissection, including medical, surgical, and endovascular options, are remarkably effective at the management of malperfusion and rupture. Unfortunately, long-term studies indicate that 30%-50% of patients need secondary procedures to treat progressive aneurysmal enlargement of the untreated aorta. The Stent-assisted balloon-induced intimal disruption and relamination in aortic dissection repair (STABILISE) technique was introduced to improve long-term outcomes. Purpose: This study aims to investigate the results of the STABILISE technique in patients with aortic dissection. Methods: This is a single-center, retrospective review of all patients treated with the STABILISE technique. There were 12 de novo type B aortic dissection (TBAD) and 7 residual TBAD following type A aortic dissection (TAAD) repair. Results: There was disruption of the dissection membrane and relamination in all or part of the bare metal stent segment in 100% of cases. The average percent attainment of a uni-luminal aorta in comparison to the length with persistent false lumen was 91 ± 12%. Conclusion: Midterm results suggest that the STABILISE technique may improve aortic remodeling after endovascular treatment of acute dissection.

Emerging Trends in the Care of Type B Aortic Dissections

Aortic dissection is the most common of the acute aortic syndromes. Acute aortic dissection remains a highly morbid and potentially lethal condition despite contemporary advances in medical and surgical care. Type B aortic dissection (TBAD) is classified as uncomplicated, uncomplicated with high-risk features, and complicated. The role of thoracic endovascular aortic repair (TEVAR) in uncomplicated TBAD remains uncertain and is the topic of ongoing clinical trials. In most complicated cases, TEVAR is effective at restoring visceral and extremity blood flow. TEVAR has also been shown to arrest hemorrhage in the setting of thoracic aortic rupture. TEVAR has been demonstrated to induce satisfactory remodeling in the covered segment of the thoracic aorta, but progressive enlargement of the visceral aorta has led to a variety of techniques designed to promote remodeling in the uncovered aortic segment. There is a need to better define high-risk features so that treatment can be tailored to specific clinical conditions.

Urgent Candy-Plug technique for distal false lumen occlusion in chronic aortic dissection

OBJECTIVE

This study aimed to assess the impact of urgency on early and midterm outcomes of the Candy-Plug (CP) technique for distal false lumen (FL) occlusion in thoracic endovascular aortic repair for aortic dissection.

METHODS

The CP registry was reviewed, and patients were categorized into elective and urgent/emergent groups for analysis. End points included technical success, clinical success, early (30-day) computed tomography angiography findings, early (30-day) mortality, adverse events, and aortic remodeling in patients with available computed tomography angiography follow-up and reintervention.

RESULTS

A total of 155 patients received a custom-made CP, of whom 32 patients (44% male, mean age 61 ± 9 years) were treated urgently and 123 patients (63% male, mean age 62 ± 11 years) electively. The primary CP rate was higher in the urgent group (28/32, 88%, in the urgent group vs 96/123, 78%, in the elective group, P = .051). The mean contrast volume was higher in the urgent group (157 ± 56 mL in the urgent group vs 130 ± 71 mL in the elective group, P = .017). Technical success was achieved in all patients in both groups. Clinical success was achieved in 25 of 32 (78%) patients in the urgent group vs 113 and 123 (92%) in the elective group (P = .159). The early mortality rate was 13% (4 of 32 patients) in the urgent group vs 1% (1 of 123 patients) in the elective group (P = .120). There was no statistically significant difference regarding the early adverse events between the urgent and elective CP groups. Early aortic-related reinterventions were required in 6 of 32 (19%) patients in the urgent group vs 6 of 123 (5%) in the elective group (P = .094). Thoracic aortic aneurysm sac regression was lower in the urgent group (5/28, 18%, in the urgent group vs 63/114, 55%, in the elective group, P = .001). Stable thoracic aortic aneurysm sac was higher in the urgent group (22/28, 79%, in the urgent group vs 47/114, 41%, in the elective group, P = .000). An increase in thoracic aortic aneurysm sac occurred in 1 of 28 (4%) patients in the urgent group vs 4 of 114 (4%) patients in the elective group (P = .096).

CONCLUSIONS

The urgent use of the CP technique for distal FL occlusion in aortic dissection was feasible and effective. The decrease in aortic FL sac diameter may be affected by the urgent use of CP due to limited sizing availability. However, it achieved a high rate of aortic remodeling.

Long-Term Outcomes of PETTICOAT Technique-Assisted Thoracic Endovascular Aortic Repair for the Treatment of Acute and Subacute Complicated Type B Aortic Dissection

OBJECTIVE

To evaluate the long-term outcomes of the provisional extension to induce complete attachment technique (PETTICOAT) for the treatment of acute and subacute complicated type B aortic dissection (TBAD).

METHODS

We retrospectively collected and analyzed the clinical data of patients with acute and subacute TBAD who were treated using the PETTICOAT technique at our center between March 2014 and March 2023. The primary endpoint was all-cause mortality; secondary endpoints were a composite of complications, such as entry flow, stent-graft-induced new entry (SINE), and re-intervention.

RESULTS

The technical success was 92% (46/50). The perioperative mortality was 2% (1/50), and the procedure-related re-intervention was also 2% (1/50). The mean follow-up time was (74.9±33.9) months. The mortality was 4.1% (2/49). The incidence of aortic-related complications was 8.2% (4/49), including new entry flow, 2 retrograde type A aortic dissections, and 1 distal stent graft-induced new entry SINE. The procedure-related re-intervention rate was 4.1% (2/49). After 5 years of follow-up, the total aortic diameter at the renal artery level was reduced from that at the third year of follow-up but was still significantly larger than preoperatively (26.9±6.6 mm vs. 24.1±4.2 mm, p=0.013). While at the covered stent, bare stent, stentless, and celiac artery (CA) levels, the total aortic diameters did not change significantly compared with preoperative values, whereas true lumen (TL) diameters and TL ratios were maintained at obviously higher levels than preoperative. The rate of complete thrombosis of false lumen in the thoracic aortic segment was significantly higher than that in the abdominal aortic segment (79.6% vs 30.6%, p=0.0001).

CONCLUSIONS

The results indicated that the PETTICOAT technique is safe and effective and could promote positive remodeling of the aorta from the level of the covered stent to the CA. Remodeling of the distal abdominal aorta may fluctuate and requires close follow-up review.

CLINICAL IMPACT

The long-term results from our center suggest that the PETTICOAT technique promotes positive remodeling of the aorta from the level of the covered stent to the CA; whereas this advantage does not seem to be significant in the more distal segment of the abdominal aorta, mainly at the level of RA and distal. Therefore, further procedures may be required for aortic dissection of the abdominal segment. In addition, aortic remodeling may fluctuate to some extent during the follow-up period, especially in the abdominal visceral region, so close follow-up review is quite important, and prompt re-intervention is required if necessary.

Physician-modified funnel-shaped covered stent for selective false lumen exclusion in chronic type B aortic dissection

PURPOSE

To describe the technique of off-centering a balloon-expandable covered stent for selective occlusion of a distal entry tear (ET) in a patient, conservatively treated for chronic type B aortic dissection (cTBAD), presenting FL expansion.

TECHNIQUE

A 63-year-old male, with conservatively managed cTBAD, presented at follow-up with FL partial thrombosis and expansion (thoracic aorta FL from 21 mm to 27 mm and abdominal aorta FL from 11 mm to 15 mm in 6 months). No proximal ET was identifiable. Distal FL perfusion was caused by an ET in the abdominal aorta feeding a 2 mm accessory renal artery (ARA). As the aortic diameter was below the threshold for endovascular repair, a selective occlusion of the distal ET and ARA was planned. A balloon-expandable covered stent was modified by off-centering the covered stent proximally and resulting in a funnel-shape occluder after deployment across the ET into the ARA. To prevent type Ic endoleak due to possible FL expansion caused by an intra-operatively detected phrenic artery (PA), coils were deployed into the lumen of the modified stent and the ARA. The pre-discharge computed tomography angiography showed exclusion of both the ARA and ET and a type 2 endoleak from the PA.

CONCLUSION

A balloon-expandable covered stent can be modified by off-centering the covered stent resulting in a funnel shape to adapt to different diameter requirements.

Transcatheter electrosurgical aortic septostomy optimizes distal landing zone in chronic dissection

Objective

Efficacy of thoracic endovascular aortic repair (TEVAR) for chronic type B aortic dissection (CTBAD) is dependent on eliminating retrograde false lumen perfusion and remodeling the aorta. We describe the efficacy of a novel transcatheter electrosurgical technique to fenestrate the dissection flap and create a distal seal zone for TEVAR in CTBAD.

Methods

A retrospective review of the Emory Aortic Database from 2016 to 2023 identified 33 patients who underwent TEVAR with intentional endovascular rupture of the dissection flap (Knickerbocker; KNICK) for CTBAD. In 11 patients, we performed transcatheter electrosurgical aortic septostomy (TECSAS) before KNICK. The technical aspects of TECSAS + KNICK are described and results compared with TEVAR + KNICK alone.

Results

Dissection chronicity, aortic size, and preoperative demographics were similar between groups. Technical success was 100%, with zero stroke or paraplegia in both groups. Thirty-day mortality for TECSAS versus KNICK was 0% versus 13.6% (P = .199). Median follow-up was shorter after TECSAS versus KNICK, although not statistically significant (14.6 months vs 21.9 months; P = .065). Elimination of retrograde false lumen perfusion (TECSAS 100% vs KNICK 68.2%; P = .035) and complete false lumen thrombosis or obliteration (TECSAS 91.9% vs KNICK 54.6%; P = .037) were more frequent after the TECSAS procedure. Aortic reinterventions were less frequent after TECSAS versus KNICK (0% vs 13.6%, P = .199), although not statistically significant.

Conclusions

The addition of TECSAS to intentional endovascular rupture of the dissection flap in CTBAD improves distal seal, eliminating retrograde false lumen perfusion. This technique is a safe and precise method to fenestrate a dissection flap and optimize TEVAR in CTBAD.

Initial Single-Center Experience With the Knickerbocker Technique During Thoracic Endovascular Aortic Repair to Block Retrograde False Lumen Flow in Patients With Type B Aortic Dissection

OBJECTIVE

Effectiveness of thoracic endovascular aortic repair in type B aortic dissection is impaired by persistent retrograde false lumen flow via distal re-entry tears. Controlled, stentgraft-assisted balloon dilatation of the true lumen at its lower end, or Knickerbocker technique, may block retrograde false lumen flow and consequently improve effectiveness by inducing immediate thrombosis along the entire descending thoracic aorta.

MATERIALS AND METHODS

A single-center retrospective analysis was performed for all consecutive patients with aortic dissection treated with the Knickerbocker technique to block retrograde false lumen flow.

RESULTS

Eleven patients were included for analysis. Intraoperative control angiography showed successful occlusion of the false lumen at the level of balloon dilatation in 9 out of 11 patients (82%). There was one perioperative mortality (9%), due to stroke. There were 2 early reinterventions, due to retroperitoneal bleeding and due to chyle leakage in the neck after left subclavian artery bypass. Median clinical follow-up duration was 6 (interquartile range [IQR] 2-11] months. There were 2 deaths during follow-up, one at 2 months after TEVAR from unknown cause of death, and one after 11 months due to rupture of an ascending aortic pseudoaneurysm. The Knickerbocker technique led to positive aortic remodeling. At 3 months follow-up, 100% of patients showed complete false lumen thrombosis in the thoracic aorta proximal to the level of balloon dilatation, with decreasing false lumen diameters (100%) and stable (44%) or decreasing (56%) total aortic diameters. In most patients, the false lumen distal to the stentgraft (i.e. at visceral level) remained patent (11% false lumen thrombosis rate), leading to ≥2 mm dilatation at this level (78% of patients) and in the infrarenal abdominal aorta (56% of patients) at 3 months postoperatively. No distal stent-graft-induced new entry tears were noticed during follow-up.

CONCLUSION

The Knickerbocker technique is feasible and effective, leading to positive aortic remodeling of the aorta covered by stentgraft in all of a small cohort of patients.

CLINICAL IMPACT

Persistent, retrograde false lumen perfusion from distal re-entries following thoracic endovascular aortic repair (TEVAR) for Stanford type B aortic dissection, may lead to progressive, aneurysmal dilatation. Controlled, stent graft-assisted balloon dilatation of the true lumen in the distal descending aorta (i.e. Knickerbocker technique) during TEVAR effectively excludes the false lumen from persistent flow resulting in positive aortic remodeling in our small cohort of patients, and hence potentially eliminates the risk of late post-dissection aneurysm formation in the descending thoracic aorta.

Efficacy of intentional undersized thoracic endovascular repair for Stanford type B aortic dissection

OBJECTIVE

Thoracic endovascular aneurysm repair (TEVAR) is widely used for the treatment of aortic dissection. Endograft oversizing is a risk factor for stent graft-induced new entry tears and retrograde type A aortic dissection. However, there is no clear consensus on the optimal graft size selection for Stanford type B acute or subacute aortic dissection (TBAD). Herein, we examined the safety and efficacy of TEVAR using an intentionally undersized endograft to treat TBAD.

METHODS

This retrospective chart review study included 82 patients who underwent TEVAR for acute or subacute Stanford TBAD between 2015 and 2022. We measured the true lumen diameter just distal to the subclavian artery and opted for a stent graft of the same diameter. In instances where deformation resulting from false lumen pressure displacement was pronounced, we measured the diameter at the site just proximal to the subclavian artery. Patients' characteristics, procedural, in-hospital, and follow-up data, and aortic remodeling were analyzed. The aortic diameter was analyzed using one-way analysis of variance followed by Dunnett's test. Survival and freedom from reintervention were estimated using Kaplan-Meier curves.

RESULTS

The follow-up rate was 98.4%. The mean age was 58.3 ± 12.3 years, and 76 were men (92.7%). The mean diameters of the stent graft and native proximal landing zone were 30.9 ± 3.2 mm and 30.8 ± 3.0 mm, respectively. The oversize rate of the stent graft in relation to the native proximal aortic diameter was 0.3% ± 4.7%. In-hospital mortality was observed in one patient, retrograde type A aortic dissection in one patient, distal stent graft-induced new entry tear in zero patients, and type 1a endoleak in 22 patients (26.8%). Type 1a endoleaks, characterized by antegrade false lumen blood flow originating from the primary entry, in 12 patients spontaneously disappeared within 1 year of follow-up. According to aortic remodeling, 59 patients (86.8%) achieved complete aortic remodeling at the aortic arch level and 51 (75.0%) at the eighth thoracic vertebral level. The diameters of the aortic arch and descending aorta were significantly reduced compared with the postoperative measurements (P <.001). Survival rates were 97.5% and 93.6% at 1 and 3 years, respectively. Freedom from reintervention was 84.7% and 84.7% at 1 and 3 years, respectively.

CONCLUSIONS

Intentionally undersized TEVAR was safe and achieved acceptable aortic remodeling despite a high rate of type 1a endoleaks. A type 1a endoleak was acceptable as it primarily diminished during the mid-term follow-up.

Discussing on the Aortic Coverage in Type B Aortic Dissection Treatment: A Comprehensive Scoping Review

OBJECTIVE

The objective of this study is to investigate and address the question surrounding the determination of the optimal endograft length of coverage during TEVAR for type B aortic dissection (TBAD), with a particular emphasis on the distal landing zone (DLZ).

DATA SOURCES

MEDLINE, Scopus, and Web of Science databases were used.

METHODS

The PRISMA-ScR statement was followed.

RESULTS

Several variables can contribute to the length of coverage during TEVAR in TBAD patient. Baseline patient's characteristics, TBAD-related features, the type of endoprosthesis, and postoperative graft behaviour may contribute to the choice of coverage.

CONCLUSIONS

No robust data have been published regarding the optimal length of TEVAR. Therefore, reporting the percentage of covered aorta and improving computational studies should be valorised to improve postoperative outcomes.

Design, evolution, and experience with the candy plug device for endovascular false lumen occlusion of chronic aortic dissections

INTRODUCTION

The management of the false lumen (FL) when dealing with aortic dissection is a crucial aspect since inducing its thrombosis is necessary in order to achieve aortic remodeling. One of the pitfalls of endovascular treatment of aortic dissection (AD) is retrograde distal FL perfusion and pressurization, which prevents FL thrombosis and thus aortic remodeling, while being associated with aneurysmal degeneration of the FL and poor long-term outcomes.

AREAS COVERED

Currently, there is no CE/FDA approved device for FL closure, however different techniques and devices have been proposed to overcome this challenge, the most known of which is the Candy Plug (CP). This review aims to describe the CP device, its implantation technique, and the available data in the literature (PubMed, Cochrane, and EMBASE databases; last queried, December 31, 2023).

EXPERT OPINIONS

While the treatment of AD remains technically challenging, the use of the CP technique to close any distal FL reperfusion proved to be feasible and safe with excellent rates of both technical and clinical success. Furthermore, recent studies have shown a quick learning curve with this technique.

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.

Dissection flap fenestration can reduce re-apposition force of the false lumen in type-B aortic dissection: a computational and bench study

Thoracic endovascular aortic repair (TEVAR) has been widely adopted as a standard for treating complicated acute and high-risk uncomplicated Stanford Type-B aortic dissections. The treatment redirects the blood flow towards the true lumen by covering the proximal dissection tear which promotes sealing of the false lumen. Despite advances in TEVAR, over 30% of Type-B dissection patients require additional interventions. This is primarily due to the presence of a persistent patent false lumen post-TEVAR that could potentially enlarge over time. We propose a novel technique, called slit fenestration pattern creation, which reduces the forces for re-apposition of the dissection flap (i.e., increase the compliance of the flap). We compute the optimal slit fenestration design using a virtual design of experiment (DOE) and demonstrate its effectiveness in reducing the re-apposition forces through computational simulations and benchtop experiments using porcine aortas. The findings suggest this potential therapy can drastically reduce the radial loading required to re-appose a dissected flap against the aortic wall to ensure reconstitution of the aortic wall (remodeling).

Use of Iliac Branch Endoprosthesis to Rescue Inadvertent False Lumen Deployment of the Innominate Branch Stent During Physician-Modified Fenestrated-Branched Aortic Arch Repair

A 70-year-old male with a history of 3 prior median sternotomies and on anticoagulation presented with acute chest and back pain associated with a pseudoaneurysm of the ascending and aortic arch in the setting of residual dissection involving the innominate, proximal right carotid, and subclavian arteries. A physician-modified triple vessel fenestrated-branched arch endograft was deployed. The innominate branch stent was deployed from the right carotid cut down, while the left carotid and left subclavian branch stents were placed from a femoral approach. Postoperatively, the innominate branch was found to be deployed in the false lumen of the dissected native innominate artery, leading to continued pressurization of the pseudoaneurysm. This was rescued by placing a Gore Iliac Branch Endoprosthesis (IBE) into the innominate branch through a temporary conduit sewn to the right carotid artery with a right subclavian branch placed via a brachial artery cut down into the internal iliac gate. The use of IBE allowed branch stent extension past the dissected native vessels. The patient had an uneventful recovery without neurologic complications. At 3-month follow-up, the patient remains well with an excluded pseudoaneurysm, and patent bifurcated innominate, bilateral carotid, and subclavian artery branches. A Gore IBE can be utilized in a dissected innominate artery to create an innominate branch device during fenestrated-branched endovascular arch repair.

How to treat type 1b endoleakage-extension, fEVAR, bEVAR, or open repair

Thoracic endovascular aneurysm repair has been well described in the literature as a treatment for a wide range of thoracic aortic pathologies. As with any intervention, there remains a risk of an unfavorable outcome, including endoleak, a term used to describe unexpected blood flow between the stent-graft and the wall of the excluded aneurysm. Endoleaks cause pressurized enlargement of the aneurysmal sac and may lead to catastrophic outcomes such as rupture and death. Type 1b endoleak represents a distal landing zone that is compromised by retrograde blood flow. Moreover, there is a lack of data on type 1b endoleaks and its management options. With the increase in emerging endovascular techniques and technologies, endoleaks are more frequent. However, the management of endoleaks is not standardized among different centers. The purpose of this article is to provide an overview of type 1b endoleaks after thoracic endovascular aneurysm repair, current management options, and our experience.

Custom Made Candy Plug for Distal False Lumen Occlusion in Aortic Dissection: International Experience

OBJECTIVE

To evaluate early and midterm outcomes of the Candy Plug (CP) technique for distal false lumen (FL) occlusion in thoracic endovascular aortic repair for aortic dissection (AD) in a more real world cohort of patients from an international multicentre registry.

METHODS

A multicentre retrospective study was conducted of all consecutive patients from the contributing centres with subacute and chronic AD treated with the CP technique from October 2013 to April 2020 at 18 centres.

RESULTS

A custom made CP was used in 155 patients (92 males, mean age 62 ± 11 years). Fourteen (9%) presented with ruptured false lumen aneurysms. Technical success was achieved in all patients (100%). Clinical success was achieved in 138 patients (89%). The median hospital stay was 7 days (1 - 77). The 30 day mortality rate was 3% (n = 5). Stroke occurred in four patients (3%). Spinal cord ischaemia occurred in three patients (2%). The 30 day computed tomography angiogram (CTA) confirmed successful CP placement at the intended level in all patients. Early complete FL occlusion was achieved in 120 patients (77%). Early (30 day) CP related re-intervention was required in four patients (3%). The early (30 day) stent graft related re-intervention rate was 8% (n = 12). Follow up CTA was available in 142 patients (92%), with a median follow up of 23 months (6 - 87). Aneurysmal regression was achieved in 68 of 142 patients (47%); the aneurysm diameter remained stable in 69 of 142 patients (49%) and increased in five of 142 patients (4%). A higher rate of early FL occlusion was detected in the largest volume centre patients (50 [88%] vs. 70 [71%] from other centres; p = .019). No other differences in outcome were identified regarding volume of cases or learning curve.

CONCLUSION

This international CP technique experience confirmed its feasibility and low mortality and morbidity rates. Aortic remodelling and false lumen thrombosis rates were high and support the concept of distal FL occlusion in AD using the CP technique.

Type Ib endoleak repaired with a thoracic endovascular graft inside previous visceral debranching bypass in a patient with chronic type B aortic dissection

We present the case of a patient with chronic type B aortic dissection with a previous iliac to visceral debranching graft and thoracoabdominal endograft who, because of a type Ib endoleak and aortic diameter enlargement, required a complex solution involving placement of a thoracic endovascular graft inside a Dacron graft with a 180° curved shape in three-stage surgery. At 9 months of follow-up, he had no evidence of type I endoleaks, and the aortic diameter had decreased.

Mid-term results of distal anastomosis to the true lumen for chronic type B aortic dissection

We investigated whether distal anastomosis to the true lumen in open surgical repair of descending aorta for chronic type B aortic dissection improved the long-term outcomes with aortic remodeling. We retrospectively reviewed 71 patients with chronic type B aortic dissection, excluding those with connective tissue disorder, from October 2001 to June 2021. The patients who underwent distal true lumen anastomosis (group T, n = 36) were compared to those with both lumens' anastomosis (group B, n = 35), regarding survival, overall and distal aortic events. The growth rates of the distal aorta (maximum diameter in descending thoracic, suprarenal and infrarenal abdominal aorta) were also investigated. Median age was significantly higher in group T (T; 66 vs B; 60, P = .001). Group T had significantly higher rates of complete and partial thrombosis formation in the false lumen than group B postoperatively (26.9 vs 0%, P = .01 for complete, 65.4 vs 3.9%, P < .0001 for partial, respectively). At median follow-up for 6.8 years of 63 patients (88.7%), survival, overall and distal aortic event-free rates, and the growth rates of the distal aorta were not significantly different between the groups. Distal anastomosis to the true lumen did not improve mid-term survival, aortic event-free rates and the growth rates of the distal aorta compared with that of both lumens for chronic type B aortic dissection.

The Caged Knickerbocker: A Novel Modification to Targeted False Lumen Management in Complex Aortic Dissection

INTRODUCTION

Targeted false lumen management has been described for complex presentations of aortic dissection. The "Knickerbocker" technique is often referenced and includes dilating a focal portion of an oversized endograft in the true lumen to purposefully rupture the false lumen septum, but at the expense of increased risk for visceral propagation and malperfusion. This case series describes a novel modification of the Knickerbocker technique by caging the distal end of the endograft prior to focal dilation.

METHODS

A retrospective chart review was conducted at a tertiary academic center from 2018-2020. Patients were included if they had a history or current presentation of aortic dissection and underwent a Caged Knickerbocker (CKB) repair. Data were collected to include demographics, indications for repair, technical success, perioperative outcomes, hospital course, mortality, and further aortic interventions.

RESULTS

Five patients were included in our evaluation. Four patients (80%) presented with chronic Type B aortic dissection (cTBAD) and concomitant aneurysmal degeneration of the thoracic aorta; 1 patient (20%) presented with an acute rupture secondary to cTBAD. Three patients (60%) had previous aortic repairs, 2 of which were for Type A Aortic Dissection that additionally required redo sternotomy and total arch replacement prior to CKB. CKB was technically successful in all cases with no peri-operative complications. Two (40%) patients required further aortic intervention due to aneurysmal degeneration.

CONCLUSION

Achieving complete false lumen thrombosis is a considerable challenge when managing complex aortic dissections. Our data demonstrate the technical feasibly and early successful outcomes with the CKB approach. Importantly, CKB facilitates future distal extension into the para-visceral aorta in cases of complex thoracoabdominal aortic aneurysms. Further research should focus on discerning individual patients who will benefit from targeted false lumen management and compare outcomes between different approaches.

Intimal Tear Closure by False Lumen Stent Grafts placement for Post-dissection Thoracoabdominal Aortic Aneurysm

We report a false lumen (FL) stent graft technique to close the intimal tears at the visceral segment for a postdissection thoracoabdominal aneurysm after initial thoracic endovascular aortic repair. Following endovascular abdominal aortic repair, a stent graft was deployed in the FL, overlapping the main bodies from both previous repairs just after a bare metal stent was implanted in the FL proximal to the target lesion to prevent overdilation. A reentry tear at the iliac level was intentionally preserved to protect spinal cord perfusion and develop a collateral network and will be closed in the future staged procedure.

Managing False Lumen Patency in Chronic Thoracic Aortic Dissecting Aneurysms With Coil Embolization

Thoracic endovascular aortic repair has become the preferred modality of treatment of complicated type B aortic dissections. However, persistent pressurization of the false lumen can lead to negative aortic remodeling with aneurysmal dilation. Described herein is the coil embolization technique that can be used to manage this complication and a review of the literature on the recent development of management options.

Reverse Cheese-Wire Septotomy to Create a Distal Landing Zone for Thoracic Endovascular Aortic Repair

PURPOSE

The objective of this study is to describe a novel method for creating a distal landing zone for thoracic endovascular aortic repair (TEVAR) in chronic aortic dissection. The technique is described in a patient with prior total arch and descending aortic replacement, with false lumen expansion.

TECHNIQUE

A cheese-wire endovascular septotomy was desired to create a single lumen above the celiac axis. To avoid dividing the septum caudally across the visceral segment, we performed a modified septotomy in a cephalad direction. Stiff wires were passed into the prior surgical graft, through true lumen on the right and false lumen on the left. An additional wire was passed across an existing fenestration at the level of the celiac axis, and snared and externalized. 7F Ansel sheaths were advanced and positioned tip-to-tip at the fenestration. Using the stiff wires as tracks, the through-wire was pushed cephalad to endovascularly cut the septum. Angiogram demonstrated successful septotomy, and TEVAR was performed to just above the celiac with successful aneurysm exclusion and no endoleak or retrograde false lumen perfusion. Follow-up computed tomography angiogram (CTA) showed continued exclusion without false lumen perfusion.

CONCLUSIONS

This novel modification in a reverse direction provides an alternative method for endovascular septotomy, when traditional septotomy may threaten the visceral vessels.

Balloon Inducted Re-Lamination and False lUmen Thrombosis in Chronic Type B Aortic Dissection: Technique and Long-Term Results

BACKGROUND

To evaluate the safety, feasibility, and effectiveness of the BAlloon Inducted re-Lamination and false lUmen Thrombosis (BAILOUT) as a simple technique to address the retrograde false lumen (FL) perfusion and subsequent aneurysmatic degeneration of the thoracic aorta due to a stent-graft crimped in a small true lumen in chronic Type B dissections.

METHODS

An observational, retrospective, single-center study analyzing a nonconsecutive cohort of 8 patients affected by chronic type B aortic dissections already treated with thoracic endovascular repair and with an FL lumen backflow corrected with BAILOUT between 2006 and 2020. After a standard distal extension of the previously implanted graft, the distal end of the graft area was ballooned to completely rupture the dissection lamella to relaminate the aorta hindering the FL backflow. Computed tomography was routinely performed within the first postoperative week before discharge and then at 3 months, at 6 months, and yearly thereafter. The technical and clinical success rates were analyzed. Primary outcomes were safety and feasibility of the technique, secondary ones included FL thrombosis evaluation, and total aortic diameter analysis at the above-defined levels during the follow-up. Safety was defined if clinical success was reached. Feasibility was intended as technical success obtention.

RESULTS

The technical and clinical success achieved was 100% with the complete interruption of FL backflow stating the safety and feasibility of the BAILOUT technique. No early procedure reinterventions were recorded and during a median follow-up of 62.5 months [interquartile range 43.2-94.1], only 1 death unrelated to the procedure was recorded. Freedom from aortic-related adverse events at 1 month, 3 months, 1 year, 5, and 7 years was 87.5%, 62.5%, 62.5%, 62.5%, and 62.5%, respectively. During the follow-up, no one increment of the diameter of the thoracic aorta was documented and all the patients at 3 years of computed tomography angiography showed a complete FL thrombosis.

CONCLUSIONS

The BAILOUT technique demonstrates to be safe and feasible in this small cohort of patients as a simple and quick way to overcome the issue of FL backflow in chronic type B dissection. Small cohort and retrospective designs were limitations of the study.

Changing Management of Type B Aortic Dissections

The purpose of this manuscript is to review recent trends in the management of acute type B aortic dissection. Due to its efficacy and low morbidity, thoracic endografting has rapidly been adopted as the treatment of choice for most patients with malperfusion or rupture as a consequence of acute aortic dissection. This technology is increasingly applied to patients without rupture or malperfusion, so-called "uncomplicated" dissections, to reduce the incidence of late aneurysmal degeneration in the ungrafted segments of the thoracoabdominal aorta. A variety of techniques have been proposed, including intentional rupture of the dissection membrane to obliterate the false lumen as well as the candy-plug technique to eliminate retrograde flow in the false lumen.

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.

Transsternal and Transpericardial Approach to Descending Thoracic Aorta via Median Sternotomy-An Option for Extensive Aortic Surgery

We describe a technique for approaching the distal descending thoracic aorta via median sternotomy and posterior pericardiotomy, which enabled us to perform the extensive aortic repair. While this approach shared the lesser invasiveness of the frozen elephant trunk procedure with less confinement by anatomic features, the advantage was counterbalanced by the high incidence of spinal cord ischemia. This approach can be an option in highly selected patients who require extensive aortic repair but have factors prohibiting other conventional approaches.

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.

Fate and Consequences of the False Lumen after TEVAR in Type B Aortic Dissection

BACKGROUND

Type B aortic dissection (TBAD) occurs due to an entry tear in the intimal layer of the aorta distal to the origin of the left subclavian artery where blood enters the newly formed false lumen (FL) and extends distally or proximally to form a dissection over an indeterminate length of the aorta which, over time, may eventually rupture. Thoracic endovascular aortic repair (TEVAR) aims to seal off the entry tear proximally with the stent-graft, occluding the origin of the dissection and excluding the FL. Nevertheless, in some cases, the perfusion to the FL is maintained, hindering the aortic remodelling process and increasing the risk of aneurysmal degeneration and rupture, particularly in the abdominal aorta where evidence suggest that remodelling is slower. This review examines the long-term effects of a patent or partially thrombosed FL on clinical outcomes following TEVAR in TBAD, also highlighting the pathological processes behind negative aortic remodelling. Another aim of this review is to provide an overview and appraisal of the currently available techniques for managing a patent or partially thrombosed FL to prevent long-term morbidity occurring.

METHODS

A comprehensive literature search was performed using several search engines including PubMed, Ovid, Google Scholar, Scopus, and Embase to identify and extract relevant studies.

RESULTS

Evidence in the literature show that a partially thrombosed FL is more dangerous than a patent FL due to the occlusion of the distal re-entry tears, impeding outflow and increasing mean arterial and diastolic pressures, whereas the latter is decompressed via distal re-entry sites. FL thrombosis and satisfactory remodelling is sometimes achieved in as few as 40% of patients after TEVAR due to the maintained perfusion of the FL either at the level of the thoracic or abdominal aorta. However, although the thoracic aorta is predominantly covered by the TEVAR stent-graft, poorer remodelling and more dilation is seen in the abdominal aorta. Several techniques are available to embolize the FL, including the Provisional Extension to Induce Complete Attachment, Stent Assisted Balloon Induced Intimal Disruption and Relamination in Aortic Dissection Repair, candy-plug, and Knickerbocker techniques.

CONCLUSIONS

The management of TBAD is invariably TEVAR to seal off the proximal entry tear while extending the repair distally to completely exclude the FL. A risk of aortic wall dilatation distal to TEVAR stent-graft remains; hence, regular monitoring and accurate imaging are essential. At present, a patent FL can be treated using a range of different endovascular techniques.

Chronic Thoracic Aortic Dissection: How to Treat, When to Intervene

Thoracic aortic dissection (AD) is associated with increased morbidity and mortality. Acute aortic syndrome is the first presentation of the disease in most cases. While acute AD management follows concrete guidelines because of its urgent and life-threatening nature, chronic AD is usually overlooked, although it concerns a wide spectrum of patients surviving an acute event. Acute AD survivors ultimately enter a chronic aortic disease course. Patients with chronic thoracic AD (CTAD) require lifelong surveillance and a proportion of them may present with symptoms and late complications demanding further surgical or endovascular treatment. However, the available data concerning the management of CTAD is sparse in the literature. The management of patients with CTAD is challenging as far as determining the best medical therapy and deciding on intervention are concerned. Until recently, there were no guidelines or recommendations for imaging surveillance in patients with chronic AD. The diagnostic methods for imaging aortic diseases have been improved, while the data on new endovascular and surgical approaches has increased significantly. In this review, we summarize the current evidence in the diagnosis and management of CTAD and the latest recommendations for the surgical/endovascular aortic repair of CTAD.

Procedure and Aortic Remodeling Effects of Entry Closure with Stentgraft for Type B Aortic Dissection: Comparison between the Patients with Narrow True Lumen and Those with Aneurysmal Dilated False Lumen

Objectives: Appropriateness of device selection, procedure protocol and aortic remodeling effects of entry closure (TEVAR) with stent-graft (SG) for patent false lumen type B aortic dissection (TBAD) were compared between the patients with narrow true lumen (narrow group) and those with aneurysmal dilated false lumen (aneurysmal group).

Methods: Twenty-six patients with narrow true lumen (narrow group) and 20 patients with aneurysmal false lumen (aneurysmal group) were included in this study. In narrow group, straight SG was implanted from Zone 3 regardless the distance between the left subclavian artery and entry. In aneurysmal group, straight or taped SG was implanted with proximal landing zone length 20 mm or more. Thoracic aortic anatomy was evaluated by CT and aortic remodeling was defined as true lumen diameter ≥50% of the aortic diameter and occlusion of false lumen. Aorta related death, retrograde type A aortic dissection (RTAD), stentgraft induced new entry (SINE) and aortic maximum diameter enlargement 5 mm or more (aortic expansion) were included in the aortic event.

Results: There was no procedure related complication in narrow group and 1 patient died due to aortic rupture in aneurysmal group, Type Ia endoleak by enhanced CT 7 days after TEVAR was detected in one patient in each group. Achievement of aortic remodeling was significantly better in narrow group. Aortic event occurred in only one patient in narrow group, in whom aortic expansion was observed. In aneurysmal group, aortic event occurred 12 patients (60%) and 2 RTAD, 5 SINE, and 8 aorta expansion were observed. Aortic event free rate was significantly better in narrow group.

Conclusion: TEVAR procedure for the TBAD patients with narrow true lumen seemed to be appropriate, however, different TEVAR procedure or additional procedures would be required for those with aneurysmal dilated false lumen to obtain favorable outcomes. (This is secondary publication from Jpn J Vasc Surg 2021; 30: 347–357.)

TEVAR and EVAR, the unknown knowns of the cardiovascular hemodynamics; and the immediate and long-term consequences of fabric material on major adverse clinical outcome

This review discusses the impact of endovascular aneurysm repair on cardiovascular (CV) hemodynamics and the role of stent-graft material, i.e., polytetrafluoroethylene (PTFE) vs. polyester in post-procedural outcomes. Endovascular aneurysm repair has been widely employed in the last decades for thoracic and abdominal aneurysm repair. However, aortic endografts are stiff and alter the native flow hemodynamics. This failure to simulate the native aorta could lead to added strain on the heart, manifesting as increased left ventricular strain, higher pulse pressure, and congestive heart failure later. This could result in adverse CV outcomes. Also, evidence is mounting to support the implication of stent-graft materials, i.e., PTFE vs. polyester, in adverse post-procedural outcomes. However, there is an absence of level one evidence. Therefore, the only way forward is to plan and perform a randomised controlled trial to demonstrate the alterations in the CV hemodynamics in the short and long run and compare the available stent-graft materials regarding procedural and clinical outcomes. We believe the best solution, for now, would be to reduce the stented length of the aorta. At the same time, in the longer term, encourage continuous improvement in stent-graft materials and design.

Beta-blocker Use After Thoracic Endovascular Aortic Repair in Patients with Type B Aortic Dissection Is Associated with Improved Early Aortic Remodeling

OBJECTIVE

Beta-blockers are first-line anti-impulse therapy in patients presenting with acute type B aortic dissection (TBAD). However, little is understood about their impact after aortic repair. The aim of this study was to evaluate the role of postoperative beta-blocker use on outcomes of thoracic endovascular aortic repair (TEVAR) in TBAD.

METHODS

The Vascular Quality Initiative database was queried for all patients undergoing TEVAR for TBAD from 2012 to 2020. Aortic-related reintervention, all-cause mortality and effect of TEVAR on false lumen thrombosis of the treated aortic segment were assessed and compared between patients treated with and without beta-blocker postoperatively. Cox proportional hazards models were used to estimate the effect of beta-blocker therapies on outcomes.

RESULTS

1,114 patients undergoing TEVAR for TBAD were identified with a mean follow-up of 18±12 months. The mean age was 61.1±11.9 years, and 791 (71%) were male. 935 (84%) patients were maintained on beta-blocker at discharge and follow-up. Patients on beta-blocker were more likely to have an entry tear originating in zones 1-2 (22% vs 13%; P=.022). The prevalence of acute, elective and symptomatic AD, concurrent aneurysm, number of endografts used, distribution of the proximal and distal zones of dissection and operative time were comparable between the two cohorts. At 18-months, significantly more complete false lumen thrombosis (58 vs 47%; log-rank P=.018) was observed in patients on beta-blocker while the rates of aortic-related reinterventions (13% vs 9%; log-rank P=.396) and mortality (0.2% vs 0.7%; log-rank P=.401) were similar in patients with and without beta-blocker, respectively. Even after adjusting for clinical and anatomic factors, postoperative beta-blocker use was associated with increased complete false lumen thrombosis (HR 1.56; 95% CI: 1.10-2.21; P=.012) but did not affect mortality or aortic-related reintervention. A secondary analysis of beta-blocker use in acute versus chronic TBAD showed a higher rate of complete false lumen thrombosis in patients on beta-blocker in chronic TBAD (59% vs 38%; log-rank P=.038). In contrast, there was no difference in the rate of complete false lumen thrombosis in acute TBAD between the two cohorts (58% vs 51%; log-rank P=.158). When analyzed separately, postoperative ACE inhibitor use did not affect the rates of complete false lumen thrombosis, mortality and aortic-related reintervention.

CONCLUSIONS

Beta-blocker use was associated with promotion of complete false lumen in patients undergoing TEVAR for TBAD. In addition to its role in acute setting, anti-impulse control with beta-blocker appears to confer favorable aortic remodeling and may improve outcomes after TEVAR, particularly for chronic TBAD.

[Chronic type B aortic dissection-what to do?]

BACKGROUND

Chronic type B aortic dissection requires optimal medical therapy. However, secondary complications like organ or extremity malperfusion or development of aneurysmal dilatation require interventional therapy.

OBJECTIVES

Presentation of different endovascular treatment options for complications of chronic type B aortic dissection.

MATERIALS AND METHODS

Analysis of current literature with regard to indications, techniques, results, and differential indications of interventional techniques for the treatment of chronic type B aortic dissection complications.

RESULTS

Endovascular implantation of an aortic stent graft is interventional standard therapy for treatment of aneurysmal dilatation of the aorta following type B dissection. Technical problems are the proximal and distal landing zones and the treatment of persistent flow in the false lumen.

CONCLUSION

Endovascular treatment of chronic complicated type B aortic dissection is increasingly used compared to open surgical treatment because not only are more complex stent grafts (fenestrated and branched devices) available but also because of newly developed techniques for effective occlusion of flow in the false lumen (e.g., candy plug).

Aortic remodeling after endovascular aortic repair and tailored distal entry tears exclusion in Crawford type III or IV dissection aneurysm

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) can only promote 55-80% false lumen (FL) thrombosis when only the proximal primary tear is covered during the repair of type B aortic dissection (TBAD). This study evaluated the effectiveness and clinical outcome of tailored exclusion of the primary entry tear with TEVAR and distal fenestrations with ancillary devices in patients with subacute or chronic Crawford type III and IV aortic dissection aneurysm.

METHODS

All patients underwent either TEVAR for primary entry tear; subsequently, various ancillary devices were applied on each distal fenestration. These techniques included covered stent occlusion of detached visceral artery entry tears, TL stenting and FL occlusion with vascular plugs in the common iliac artery dissection, or TEVAR coverage for multiple fenestrations from segmental arteries. This case series included nine patients (seven men and two women; mean age: 63.4 years) during January 2013 to May 2019. Outcome analysis included the rates of technical success and procedure-related complications, completeness of FL occlusion, aortic remodeling, and midterm mortality at 2 years.

RESULTS

The mean follow-up duration was 37.7 months without in-hospital mortality. One patient was lost to follow-up at the second month, the rest of patients were all alive during the follow-up period. All patients achieved complete FL thrombosis, and six patients exhibited aneurysm diameter shrinkage.

CONCLUSION

Tailored exclusion of visceral and iliac distal fenestrations with proximal primary tear coverage can promote FL thrombosis and aortic remodeling in the visceral aortic segment in patients with Crawford type III or IV aortic dissection aneurysm.

Successful Aortic Remodeling Through the Candy-Plug Technique for Chronic Type B Aortic Dissection

PURPOSE

To describe the efficiency of the candy-plug technique using an Excluder aortic extender and obtain optimal aortic remodeling.

CASE

A 46-year-old male patient had a history of acute type B aortic dissection and progressive dilation of the descending aorta (53 mm diameter) with a patent false lumen. He was treated with the candy-plug technique, using an Excluder aortic extender of 32-45 mm was placed and a 16-mm Amplatzer Vascular Plug II. No technical complications were observed in the patient. Good aortic remodeling was observed after 6 months, CT showed complete thrombosis of the false lumen and reduction of the maximum perpendicular diameter of the descending aorta from 53 to 47 mm. The diameter of the other proximal zones of the descending aorta was 45-47 mm, and the Excluder aortic extender changed into an elliptical shape. This is the first report of good aortic remodeling with an elliptical shape by performing the candy-plug technique.

DISCUSSION

The candy-plug technique using an Excluder aortic extender is an improved method for occluding the false lumen as it provides improved aortic remodeling. The 2 indications for this surgery are limited. A large entry point in the descending abdominal aorta that is more peripheral than the candy-plug position must be visible on contrast-enhanced CT and the false lumen is not too large. We consider candy-plug placement in the true lumen central to the TEVAR to avoid occluding the artery of Adamkiewicz, since we have to avoid the thrombosis of the peripheral false lumen where a candy-plug was placed. Since it is unclear whether long-term results are satisfactory, we must continue to study chronic aortic type B dissection.

The Knickerbocker Technique: Technical Aspects and Single-Center Results of a New Endovascular Method for False Lumen Occlusion in Chronic Aortic Dissection

PURPOSE

To describe the technical aspects and early results of a new endovascular fenestration method for false lumen occlusion in chronic aortic dissection: the Knickerbocker Technique.

METHODS

A retrospective observational study including all consecutively treated patients between November 1, 2012, through May 31, 2016, who underwent thoracic endovascular aortic repair with false lumen occlusion using the Knickerbocker Technique for thoracic false lumen aneurysm in chronic aortic dissection in a tertiary care center. Primary endpoints consisted of technical (correct deployment of the stent-graft) and clinical (false lumen occlusion) success. Secondary endpoints included overall survival and morbidity after 30 days. In 12 patients, follow-up computed tomography angiogram (CTA) was available and aortic remodeling was evaluated.

RESULTS

We identified 16 eligible patients (75% men, mean age: 69 years, range: 52-80 years). Technical success was 94%. Overall survival after 30 days was 100%; there was 1 aortic reintervention (additional false lumen embolization due to endoleak type 1a in 1 patient). Median total follow-up was 31.5 months (range: 3-66 months). Four (25%) of 16 patients died during follow-up, in 3 of those patients the cause of death is unknown, and 1 patient developed cardiac tamponade after being treated by fenestrated thoracic endovascular aortic repair. Imaging follow-up with CTA was available in 12 patients (median imaging follow-up: 27.5 months, range: 1-57 months). Nine (75%) of 12 patients showed thoracic aortic remodeling, and in 3 patients aneurysm size was stable. No patient showed aneurysm growth.

CONCLUSION

The Knickerbocker Technique is a feasible endovascular fenestration method to achieve false lumen occlusion and aortic remodeling in chronic aortic dissection with low invasiveness.

The STABILISE technique to address malperfusion on acute-subacute type B aortic dissections

Endovascular treatment is the current standard of care for complicated acute and subacute type B aortic dissection. Closure of the primary entry tear with thoracic endovascular aneurysm repair (TEVAR) is often insufficient to induce complete false lumen thrombosis and a positive aortic remodeling. Moreover, TEVAR does not solve all the cases of malperfusion. The Provisional ExTension to Induce COmplete ATtachment (PETTICOAT) technique (deploying self-expandable bare metal stents in the true lumen in addition to TEVAR) can re-expand the true lumen, stabilize the lamella and promote aortic remodeling, but it does not recreate a single-lumen aorta and long-term aneurysmal degeneration of the aorta is frequent. Endovascular treatment by means of TEVAR + PETTICOAT does not recreate a single-lumen aorta so long-term aneurysmal degeneration of the aorta is frequent. The stent-assisted, balloon-induced intimal disruption and relamination of aortic dissection (STABILISE) technique may help to this purpose disrupting the intimal lamella and creating a relaminated uni-luminal aorta.

Methods and outcomes of endovascular false lumen embolization for thoracic aortic dissection

PURPOSE

To provide a contemporary review on endovascular false lumen (FL) embolization for thoracic aortic dissection (AD) and evaluate its early outcome.

METHODS

A systematic literature review on FL embolization for thoracic AD from January 2003 to December 2020 was performed under the instruction of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement. Each article was analyzed using a standardized protocol including predefined demographic characteristics, perioperative mortality and major complications.

RESULTS

A total of 29 papers with 229 patients were included into the analysis. The methods of FL occlusion used were: the Candy-Plug technique, the knickerbocker technique, the "cork in the bottleneck" technique and direct FL embolization with combination of stent-grafts, coils, onyx, plugs and glue. FL embolization procedure was performed in 79 patients (34.5%) with type A AD and 150 (65.5%) with type B AD. FL direct embolization was the most frequently used technique, and it was applied in 198 (86.5%) patients. Candy-plug, knickerbocker and "cork in the bottleneck" techniques were used in 26 (11.4%), 3 (1.3%) and 2 (0.9%) patients, respectively. Technical success was achieved in all patients except one (228/229, 99.6%) in which implantation of a stent to celiac trunk was not possible. There were four hospital deaths (1.7%). Neurological complications occurred in 6 patients (2.6%), including 4 (1.7%) spinal cord ischemia and 2 (0.9%) ischemic stroke. There were 1 (0.4%) iatrogenic retrograde dissection and 2 (0.9%) renal failure reported. The mean duration of follow-up was 16.5 months. There were 21 deaths (9.3%) during follow-up, and 8 (3.6%) were aorta-related. Thirty-three (14.7%) secondary intervention were performed. Five patients (2.2%) required open completion thoracoabdominal procedure incorporating the stent-graft into the repair. Complete FL thrombosis was observed in 181 (80.4%) patients, 34 (15.1%) had partial thrombosis, and 10 (4.4%) had FL progression.

CONCLUSIONS

FL embolization of the distal thoracic aorta is a promising technique in a group of patients to promote FL thrombosis and aortic remodeling in thoracic aorta.

Imaging and Surveillance of Chronic Aortic Dissection: A Scientific Statement From the American Heart Association

All patients surviving an acute aortic dissection require continued lifelong surveillance of their diseased aorta. Late complications, driven predominantly by chronic false lumen degeneration and aneurysm formation, often require surgical, endovascular, or hybrid interventions to treat or prevent aortic rupture. Imaging plays a central role in the medical decision-making of patients with chronic aortic dissection. Accurate aortic diameter measurements and rigorous, systematic documentation of diameter changes over time with different imaging equipment and modalities pose a range of practical challenges in these complex patients. Currently, no guidelines or recommendations for imaging surveillance in patients with chronic aortic dissection exist. In this document, we present state-of-the-art imaging and measurement techniques for patients with chronic aortic dissection and clarify the need for standardized measurements and reporting for lifelong surveillance. We also examine the emerging role of imaging and computer simulations to predict aortic false lumen degeneration, remodeling, and biomechanical failure from morphological and hemodynamic features. These insights may improve risk stratification, individualize contemporary treatment options, and potentially aid in the conception of novel treatment strategies in the future.

Chronic thoracoabdominal aortic dissection: endovascular options to obliterate the false lumen

Background

Persistent false lumen patency in chronic thoracoabdominal aortic dissections after thoracic endovascular aortic repair (TEVAR) contributes to negative aortic remodeling. We have previously described the evolution of various endovascular techniques to treat persistent false lumen perfusion including false lumen embolization. Objectives of this study are to describe endovascular techniques to obliterate the false lumen and present updated outcomes in a recent series of patients undergoing false lumen embolization for chronic aortic dissection.

Methods

From January 2018 to May 2021, 17 patients with chronic dissection underwent false lumen embolization with coils, iliac plugs, and nitinol plugs. This was often in conjunction with or following TEVAR and balloon fracture fenestration. Mean follow-up 354±324 days.

Results

After false lumen embolization there was no mortality, stroke, spinal cord ischemia, or visceral and limb ischemia. No patients required dialysis, though 1 (5.9%) did experience acute kidney injury. There was 1 (5.9%) patient that required endovascular re-intervention on the thoracoabdominal aorta. No patients underwent subsequent open surgical repair.

Conclusions

TEVAR with adjunctive false lumen embolization and balloon fracture fenestration are techniques to obliterate retrograde flow into the false lumen of chronic thoracoabdominal aortic dissections in appropriately selected patients.

Non-Standard Management of Target Vessels With the Inner Branch Arch Endograft: A Single-Center Retrospective Study

PURPOSE

The purpose of this study was to evaluate early and mid-term results of non-standard management of the supraaortic target vessels with the use of the inner branch arch endograft in a single high-volume center.

MATERIAL AND METHODS

A single-center retrospective study including all patients undergoing implantation of an inner branch arch endograft from December 2012 to March 2021, who presented a non-standard management of the supraaortic target vessels (any bypass other than a left carotid-subclavian or landing in a dissected target vessel). Technical success, mortality, reinterventions, endoleak (EL), and aortic remodeling at follow-up were analyzed.

RESULTS

Twenty-four patients were included. In 17 (71%) cases, the non-standard management was related to innominate artery (IA) compromise (12 with IA dissection, 2 with short IA, 2 with short proximal aortic landing zone that required occlusion of IA, 1 with occluded IA after open arch repair). Two (8%) cases were related to an aberrant right subclavian artery (RSA), 1 patient (4%) due to the concomitant presence of a left vertebral artery (LVA) arising from the arch and an occluded left subclavian artery (LSA), and another patient presented with an occluded LSA distal to a dominant vertebral artery. Three (13%) cases were exclusively related to management in patients with genetic aortic syndromes. Twenty (83%) patients had a previous type A aortic dissection. Ten (42%) patients presented a thoracic or thoracoabdominal aortic aneurysm and 8 (33%) patients an arch aneurysm, 6 of them associated to false lumen (FL) perfusion. There were 2 (8%) perioperative minor strokes, and 1 patient with perioperative mortality. Seven patients presented an early type I endoleak, all resolved at follow-up. Seven patients required reinterventions during follow-up (7 reinterventions related to continuous false lumen perfusion, 3 related to Type Ia endoleak, 2 related to surgical bypass). All patients who presented with FL perfusion had complete FL thrombosis at follow-up. No patient presented aneurysm growth at follow-up.

CONCLUSIONS

The use of the inner branch arch endograft with a non-standard management of the supraaortic target vessels is a possible option. Despite a high reintervention rate, regression or stability of the aneurysmal diameter was achieved in all the patients with follow-up.