False lumen embolization as a rescue technique in the setting of acute and chronic dissecting aneurysms as adjunct to thoracic endovascular aortic repair

Treatment of Uncomplicated Type B Aortic Dissection: Optimal Medical Therapy vs TEVAR + Optimal Medical Therapy

Optimal Medical Therapy (OMT) has been the accepted mode of treatment for uncomplicated Type B Aortic Dissection (uTBAD). There is growing evidence that despite the short-term benefits of OMT, patients suffer deleterious consequences in the long-term with OMT alone. Thoracic Endovascular Aortic Repair (TEVAR) along with OMT has emerged as an alternative option for patients with uTBAD. This study evaluates the available literature for TEVAR + OMT as an alternative to OMT for treatment of uTBAD. In addition, issues related to TEVAR as a treatment for uTBAD are discussed.

Staged surgically created type B aortic dissection model with endovascular reintervention for different morphological features

OBJECTIVES

Understanding morphology and how this relates to treatment strategy is critical for achieving remodelling in aortic dissection. A controllable and reproducible large animal model is required for investigating new therapeutic devices and interventions.

METHODS

Our experimental protocol involved the development of surgically created type B aortic dissection (TBAD) and endovascular reintervention-induced TBAD porcine models. The sample was randomly divided into 2 groups: 1 underwent a secondary tear creation (STC) procedure and the other underwent a false lumen extension (FLE) procedure. Anatomical features were observed at 1 and 3 months, and 2 animals in each group were euthanized at 3 months after the procedures. The aorta and main branches were harvested en bloc, cross-sectioned and prepared for histological examination.

RESULTS

All surgically created TBAD models were successfully generated, and no unintended complications occurred. The endovascular reintervention-induced TBAD model was successfully created in 11 of 12 animals, with 6 in the STC group and 5 in the FLE group. In the STC group, the intraoperative mean diameter of the new secondary tear was 7.23 mm, and a slight increase was observed at first 30 days (P = 0.0026). In the FLE group, the intraoperative new propagation length was (235.80 ± 84.94) mm. The FL propagation length at the 1-month follow-up was significantly longer than that measured intraoperatively (P = 0.0362). Histological evaluation demonstrated that the elastic fibres in the media layer of the aortic wall were disrupted and appeared to be significantly stretched on the adventitial side of the false lumen.

CONCLUSIONS

Our endovascular reintervention is a reliable, minimally invasive approach for producing specific TBAD models with different morphologies.

Factors affecting distal false lumen enlargement after thoracic endovascular aortic repair for type B aortic dissection

Objective

To investigate the factors influencing distal false lumen enlargement after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection.

Materials and methods

Data were collected on patients with type B aortic dissection who underwent TEVAR from January 2008 to August 2022. Patients were divided into a distal aortic segmental enlargement (DSAE) group and a non-DSAE group based on whether the distal false lumen was dilated more than 5 mm on computed tomographic angiography (CTA) images. To analyze the independent influences on distal false lumen dilatation after TEVAR, the variables with a P value < 0.05 during univariate analysis were included in the binary logistic regression analysis model.

Results

A total of 335 patients were included in this study, with 85 in the DSAE group and 250 in the non-DSAE group. The mean age was 52.40 ± 11.34 years, 289 (86.27%) were male patients, and the median follow-up time was 6.41 (11.99-29.99) months. There were significant differences in Marfan syndrome, chronic obstructive pulmonary disease (COPD), and follow-up time between the two groups. In terms of morphology, there were statistically significant differences in the number of tears, the size of the primary tear, and the length of dissection between the two groups. Binary logistic regression analysis indicated that Marfan syndrome, COPD, and the primary tear size were associated with distal false lumen dilatation.

Conclusions

Marfan syndrome, COPD, and the primary tear size influence distal aortic segmental enlargement after TEVAR in type B aortic dissection patients.

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.

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.

Comparative Outcome Analysis of N-Butyl Cyanoacrylate Embolization of the False Lumen Versus Thoracic Endovascular Aortic Repair in Aortic Dissection

PURPOSE

To evaluate the feasibility, safety, and effectiveness of N-butyl cyanoacrylate (NBCA) embolization for the treatment of aortic dissection.

MATERIALS AND METHODS

In this single-center retrospective study conducted from February 2003 to June 2019, NBCA embolization of an aortic false lumen was attempted in 12 patients (median age, 59 y; range, 41-68 y) and thoracic endovascular aortic repair (TEVAR) was performed in 53 patients (median age, 59 y; range, 37-70 y) for aortic dissection with one or more indications of persisting pain, malperfusion, rupture or impending rupture, maximal aortic diameter ≥ 55 mm, and/or rapid aortic enlargement. The main exclusion criterion for embolization was the presence of fast blood flow in the aortic false lumen on aortography. The efficacy of NBCA embolization and TEVAR was compared by evaluating technical and clinical outcomes, repeat intervention-free survival (RFS), and overall survival (OS).

RESULTS

Technical success was achieved in 11 of the 12 patients treated with NBCA embolization (91.7%), and clinical success was achieved in 9 of these 11 (81.8%). No significant difference was found between embolization and TEVAR in clinical success rates (embolization, 81.8%; TEVAR, 84.9%; P = .409) or procedure-related complications (embolization, 1 patient [8.3%]; TEVAR, 4 patients [7.5%]; P = .701). In addition, embolization showed comparable 5-y RFS (embolization, 82.5% ± 9.3; TEVAR, 85.5% ± 4.8; P = .641) and 5-y OS (embolization, 100%; TEVAR, 95.4% ± 3.2; P = .744) rates to TEVAR.

CONCLUSIONS

NBCA embolization of the false lumen in aortic dissection seems to be a safe and effective treatment modality for the closure of false lumen in selected patients.