Anatomic suitability for “off-the-shelf” thoracic single side-branched endograft in patients with type B aortic dissection

Treatment of Type B Aortic Dissections

Treatment of patients with Type B aortic dissections (TBADs) remains challenging due to both anatomic and medical complexities. This article outlines the current management considerations for patients with TBAD.

Endovascular Treatment Options for Chronic Dissections

Aortic dissections are classified based on the location of the entry tear. A major concern in chronic aortic dissections is aneurysmal degeneration. Aneurysmal degeneration can lead to aortic expansion and potentially death. False lumen patency is a predictor of outcomes in type B aortic dissections. Thoracic endovascular aortic repair (TEVAR) can be used to treat chronic aortic dissections. TEVAR aims to occlude the false lumen to promote thrombosis and favorable aortic remodeling. However, its benefit may be limited in chronic dissection. Several techniques have been developed to treat chronic dissections with TEVAR.

Double thoracic branch endoprosthesis to repair type IA endoleak after zone 2 thoracic branch endoprosthesis

Thoracic endovascular aortic repair has become the first-line treatment modality for descending thoracic aortic diseases. Coverage of the aortic arch branches is often required to extend the proximal seal zones during thoracic endovascular aortic repair. The thoracic branch endoprosthesis (TBE) is the first US Food and Drug Administration-approved branched device for thoracic endovascular repair allowing for incorporation of the left subclavian artery. Type IA endoleak after zone 2 TBE as well as its rescue options have not been well-described. In this report, we describe two cases of failed zone 2 TBE with a type IA endoleak, rescued with proximal extension zone 0 TBE to create a sandwiched double TBE configuration. Technical considerations as well as the limitations of this technique are discussed.

How I do it: Established and novel methods for left subclavian revascularization with thoracic endovascular aortic repair

Left subclavian artery revascularization at the time of thoracic endovascular aortic repair has been the subject of discussion for over a decade. Contemporary viewpoints suggest that revascularization should be performed where possible to decrease the risk of perioperative stroke, spinal cord ischemia, and, to a lesser degree, loss of upper extremity function. In this article, we present traditional methods as well as descriptions of newer options and technology for preservation of left subclavian artery flow during thoracic endovascular aortic repair.

Sandwich thoracic branch endoprosthesis technique for endovascular repair of thoracic aortic aneurysm with aberrant right subclavian artery

Subclavian artery coverage is frequently required to achieve an adequate proximal seal during thoracic endovascular aortic repair. The thoracic branch endoprosthesis (TBE; W.L. Gore & Associates) is the first U.S. Food and Drug Administration-approved branched device for thoracic endovascular aortic repair, designed for left subclavian artery incorporation. However, anatomic suitability of the TBE has been shown to be limited. In the present report, we describe a novel technique using the TBE in a sandwich periscope configuration to allow for emergent repair of a ruptured thoracic aortic aneurysm with a highly angulated proximal seal zone and aberrant right subclavian artery.

Risk of Stroke with Thoracic Endovascular Aortic Repair of the Aortic Arch

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) involving the aortic arch is increasingly being performed and novel endografts have been developed for this procedure, but the association of stroke and relative risk of procedural techniques remains unclear. This study evaluates the procedural risk factors for stroke and mortality with zone 0-2 TEVAR.

METHODS

The Society for Vascular Surgery Vascular Quality Initiative registry was queried for patients who underwent TEVAR with proximal landing in zone 0-2 from 2013 to 2022. Emergent and ruptured cases were excluded. Primary exposure variables included proximal seal zone (0-2) and branch vessel revascularization technique: open debranching/bypass, total endovascular incorporation, or combination (at least 1 branch open and 1 branch endovascular). The primary outcome was perioperative inhospital stroke and the secondary outcome was inhospital mortality. Univariable and multivariable regression analyses were performed.

RESULTS

In total, 4,355 cases were analyzed with 350 in zone 0 (8%), 513 in zone 1 (12%), and 3,492 in zone 2 (80%). For zone 0, 1, and 2, the stroke rates were 11.1%, 5.3% and 4.7% (P < 0.0001) and inhospital mortality rates were 6.9%, 5.3% and 3.5% (P = 0.002), respectively. Branch vessel revascularization technique was associated with stroke in zone 0 with a 3-fold higher stroke rate for total endovascular incorporation of branches compared to combination and open techniques (P = 0.002). On multivariable analysis, zone 0 was independently associated with a greater than 2-fold increased odds of stroke compared to zone 2 (95% CI 1.4-3.2, P = 0.0008).

CONCLUSIONS

Stroke rate was 2-3 times higher for zone 0 TEVAR compared to zones 1 and 2. Within zone 0, total endovascular branch incorporation was associated with a 3-fold higher stroke rate than open and combination techniques. Future device design modifications and novel endovascular strategies for stroke prevention are required to make total endovascular repair of the aortic arch an acceptable alternative to combination and open debranching/bypass techniques.

Zone 2 arch repair for acute type A dissection: Evolution from arch-first to proximal-first repair

Objective

With growing experience of acute type A aortic dissection repair, Zone 2 arch repair has been advocated. The aim of this study is to compare the outcome between "proximal-first" and "arch-first" Zone 2 repair.

Methods

From January 2015 to March 2023, 45 patients underwent Zone 2 arch repair out of 208 acute type A aortic dissection repairs: arch-first, N = 19, and proximal-first technique, N = 26, since January 2021. Indications were aortic arch or descending tear, complex dissection in neck vessels, cerebral malperfusion, or aneurysm of the aortic arch.

Results

The lowest bladder temperature was higher in the proximal-first technique (24.9 °C vs 19.7 °C, P < .001). Cardiopulmonary bypass (230 vs 177.5 minutes, P < .001), myocardial ischemic (124 vs 91 minutes, P < .001), and lower-body circulatory arrest (87 vs 28 minutes, P < .001) times were shorter in the proximal-first technique. The arch-first group required more packed red blood cells (arch-first, 2 units vs proximal-first, 0 units, P = .048), platelets (arch-first, 4 units vs proximal-first, 2 units, P = .003), and cryoprecipitates (arch-first, 2 units vs proximal-first, 1 unit, P = .024). Operative mortality and major morbidities were higher in the arch-first group (57.9% vs 11.5%, P = .001). One-year survival was comparable (arch-first, 89.5% ± 7.0% vs proximal-first, 92.0% ± 5.5%, P = .739). Distal intervention was successfully performed in 5 patients (endovascular, N = 3, and open repair, N = 2).

Conclusions

Zone 2 arch repair using the proximal-first technique for acute type A aortic dissection repair yields shorter lower-body ischemic time with a warmer core temperature, resulting in shorter cardiopulmonary bypass time, less blood product use, and fewer morbidities when compared with the arch-first technique.

Anatomic Utility of Single Branched Thoracic Endograft During Thoracic Endovascular Aortic Repair

INTRODUCTION

Single branched thoracic endografts (SBTEs) have been designed for pathology requiring zone 2 seal during thoracic endovascular aortic repair (TEVAR). Numerous criteria must be met to allow for their implantation. Our aim was to analyze anatomic suitability for a next generation SBTE.

METHODS

We reviewed 150 TEVAR procedures between 2015 and 2019. Proximal seal was: zone 0 in 21 (16%), zone 1 in 4 (3%), zone 2 in 52 (40%), zone 3 in 45 (35%), and zone 4 or distal in 7 (5%). We analyzed the Zone 2 patient's angiograms and CT angiograms using centerline software to measure arterial diameters and length in relation to the left common carotid artery (LCCA), left subclavian artery (LSA) and proximal extent of aortic disease to determine if patients met anatomic criteria of a novel SBTE.

RESULTS

Zone 2 average age was 64.4 ± 16.3 years; 34 patients were male (65%). Indications for repair were aneurysm (N = 9, 17%), acute dissection (N = 14, 27%), chronic dissection with aneurysmal degeneration (N = 7, 13%), intramural hematoma (N = 9, 17%), penetrating aortic ulcer (N = 5, 10%), and blunt traumatic aortic injury (BTAI, N = 8, 15%). LSA revascularization occurred in 27 patients (52%). Overall, 20 (38.5%) of the zone 2 patients met anatomic criteria. Patients with dissection met anatomic criteria less frequently than aneurysm (33% [10 of 30] vs 64% [9 of 14]). Patients treated for BTAI rarely met the anatomic criteria (1 of 8, 13%). The main anatomic constraints were an inadequate distance from the LCCA to the LSA takeoff and from the LCCA to the start of the aortic disease process.

CONCLUSION

Less than half of patients who require seal in zone 2 met criteria for this SBTE. Patients with aneurysms met anatomic criteria more often than those with dissection. The device would have little applicability in treating patients with BTAI.

Physician-Modified Endovascular Graft for Left Subclavian Artery Fenestration during Thoracic Endovascular Aortic Repair

BACKGROUND

This study aimed to evaluate the safety and efficacy of physician-modified endovascular graft for preservation of left subclavian artery during thoracic endovascular aortic repair.

METHODS

From June 2019 to October 2022, 66 patients with a variety of thoracic aortic pathologies were treated with thoracic endovascular aortic repair using physician-modified endovascular graft left subclavian artery fenestration to achieve adequate proximal landing zone. The details of surgical techniques were described. The perioperative morbidity, mortality, and the outcomes of mid-term follow-up were analyzed.

RESULTS

Of the 66 patients (men: women, 53:13; age, 55.18 [55.18 ± 10.62] years), 53 (80.30%) presented with type B aortic dissection, 10 (15.15%) with thoracic penetrating aortic ulcer, 2 (3.03%) with thoracic aortic aneurysm, and 1 (1.52%) with left subclavian artery aneurysm. All of them underwent thoracic endovascular aortic repair using physician-modified endovascular graft left subclavian artery fenestration on the sterile back table. The technique success rate was 96.97% (n = 64). Total operation time was 92 min (interquartile range, 86-118), graft modification time was 19 min (interquartile range, 17-21), fluoroscopy time was 49 min (interquartile range, 41-62), and contrast agent dosage was 165 mL (interquartile range, 155-185). 30-day perioperative morbidities were 3 (4.55%) strokes, 1 (1.52%) retrograde type A aortic dissection, 1 (1.52%) aortic intimal intussusception, 1 (1.52%) left arm ischemia, and 3 (4.55%) type Ia endoleaks. Postoperative 30-day mortality and reintervention rates were 1.52% and 4.55%, respectively. Among the 63 patients included in the follow-up of 17 months (interquartile range, 7.75-18.25), the primary patency of left subclavian artery fenestration stents was 100%. Late complications were 1 (1.59%) distal stent graft-induced new entry and 1 (1.59%) death due to retrograde type A aortic dissection during the follow-up. The stent graft-induced new entry patient was observed with stable false lumen.

CONCLUSIONS

Thoracic endovascular aortic repair with physician-modified endovascular graft for left subclavian artery revascularization is a safe, feasible, and efficacious technique associated with high success rate. Further study is needed for long-term outcome investigation.

Endovascular Options for the Ascending Aorta and Aortic Arch: A Scoping Review

The gold standard for aneurysmal repair of the ascending aorta and the aortic arch has been open surgery with an established track record of good results in suitable patients. In recent years, with innovations in the endovascular field alternative endovascular solutions for pathologies of the aortic arch and ascending aorta became available. At first reserved only for highly selected patients unfit for open surgery, endovascular aortic arch repair is now being offered to patients with suitable anatomy in high-volume referral centers after discussion in an interdisciplinary team. The present scoping review aims at providing an overview on indications, available devices, technical aspects, and feasibility studies of endovascular arch repair both in elective and emergent situations, including also experiences and considerations from our center.

Near-wall hemodynamic changes in subclavian artery perfusion induced by retrograde inner branched thoracic endograft implantation

Objective

Left subclavian artery (LSA)-branched endografts with retrograde inner branch configuration (thoracic branch endoprosthesis [TBE]) offer a complete endovascular solution when LSA preservation is required during zone 2 thoracic endovascular aortic repair. However, the hemodynamic consequences of the TBE have not been well-investigated. We compared near-wall hemodynamic parameters before and after the TBE implantation using computational fluid dynamic simulations.

Methods

Eleven patients who had undergone TBE implantation were included. Three-dimensional aortic arch geometries were constructed from the pre- and post-TBE implantation computed tomography images. The resulting 22 three-dimensional aortic arch geometries were then discretized into finite element meshes for computational fluid dynamic simulations. Inflow boundary conditions were prescribed using normal physiological pulsatile circulation. Outlet boundary conditions consisted of Windkessel models with previously published values. Blood flow, modeled as Newtonian fluid, simulations were performed with rigid wall assumptions using SimVascular's incompressible Navier-Stokes solver. We compared well-established hemodynamic descriptors: pressure, flow rate, time-averaged wall shear stress (TAWSS), the oscillatory shear index (OSI), and percent area with an OSI of >0.2. Data were presented on the stented portion of the LSA.

Results

TBE implantation was associated with a small decrease in peak LSA pressure (153 mm Hg; interquartile range [IQR], 151-154 mm Hg vs 159 mm Hg; IQR, 158-160 mm Hg; P = .005). No difference was observed in peak LSA flow rates before and after implantation: 40.4 cm³/ (IQR, 39.5-41.6 cm³/s) vs 41.3 cm³/s (IQR, 37.2-44.8 cm³/s; P = .59). There was a significant postimplantation increase in TAWSS (15.2 dynes/cm² [IQR, 12.2-17.7 dynes/cm²] vs 6.2 dynes/cm² [IQR, 5.7-10.3 dynes/cm²]; P = .003), leading to decreases in both the OSI (0.088 [IQR, 0.063 to -0.099] vs 0.1 [IQR, 0.096-0.16]; P = .03) and percentage of area with an OSI of >0.2 (10.4 [IQR, 5.8-15.8] vs 15.7 [IQR, 10.7-31.9]; P = .13). Neither LSA side branch angulation (median, 81°, IQR, 77°-109°) nor moderate compression (16%-58%) seemed to have an impact on the pressure, flow rate, TAWSS, or percentage of area with an OSI of >0.2 in the stented LSA.

Conclusions

The implantation of TBE produces modest hemodynamic disturbances that are unlikely to result in clinically relevant changes.

Gore TAG thoracic branch endograft for treatment of a subacute type B aortic dissection complicated by rupture

An 80-year-old man presented with a subacute zone 3-5 type B aortic dissection complicated by rupture and visceral and lower extremity malperfusion. He underwent emergent zone 2 repair with a Gore TAG thoracic branch endograft with inclusion of the left subclavian artery for a dominant left vertebral artery. The patient's postoperative course was uncomplicated. Type B aortic dissections can be anatomically complex, and rupture is a rare complication in the subacute phase. We report the novel use of a Gore TAG thoracic branch endograft for the management of type B aortic dissection complicated by rupture and demonstrate its feasibility for patients with type B aortic dissection complicated by rupture.

Applicability of endovascular branched and fenestrated aortic arch repair devices to treat residual type A dissection after ascending replacement

OBJECTIVE

Endovascular repair of post-type-A aortic dissection after open ascending replacement (PTAD) has recently been shown as safe and feasible, but with limited anatomic applicability since only one stent graft was evaluated. We assessed anatomic and clinical applicability of six commercially available branched/fenestrated stent grafts for endovascular repair of PTAD.

METHODS

On postoperative CT-scans of 101 patients, we measured aortic diameter at: sino-tubular junction, supra-aortic vessels (SAV), and descending aorta, as well as the distances between these landmarks along the outer curvature of the arch and the diameters of the SAV. Anatomical applicability was evaluated according to the instructions-for-use, clinical applicability with regard to supra-aortic and iliac arteries. Assessed devices were: Cook aortic double branch; Terumo double branch; Najuta fenestrated; Endospan Nexus; Medtronic Mona LSA; and Gore TAG thoracic branch.

RESULTS

Single devices were anatomically and clinically applicable between 19/101 (Mona LSA) and 83/101 (Najuta) cases. Reasons for rejection varied considerably across devices. With all devices available, anatomical applicability was 97/101 and clinical applicability 95/101. Combinations of a fenestrated and a branched device showed the most favorable clinical applicability for a pair of two devices, ranging from 86/101 to 94/101.

CONCLUSIONS

Anatomical and clinical applicability of endovascular devices for the repair of PTAD is high for fenestrated and branched devices, and very high for the combination of fenestrated and branched devices. Manufacturers should amend specific device requirements for PTAD. Surgeons should emphasize the need for a sufficiently long and straight graft as a potential landing zone.

Transposition of Anomalous Left Vertebral to Carotid Artery During the Management of Thoracic Aortic Dissections and Aneurysms

OBJECTIVES

Preservation of antegrade flow to the left vertebral artery is often achieved by transposition or bypass to the left subclavian artery during zone 2 thoracic endovascular aortic repair (TEVAR). An anomalous left vertebral artery (aLVA) originating directly from the aortic arch is a common arch variant with a reported incidence of 4-6%. In addition, 6-10% of vertebral arteries terminate in a posterior inferior cerebellar artery (PICA), increasing the risk of stroke if not revascularized. Few series of aLVA to carotid transposition have been reported. The aim of this study was to evaluate the outcomes of patients who underwent aLVA to carotid transposition for the management of aortic disease.

METHODS

A retrospective review of all aLVA-carotid transpositions performed for the management of thoracic aortic dissection or aneurysm at a single center from 2018 to 2021 was performed. The primary outcomes were postoperative stroke and patency of the transposed aLVA. Secondary outcomes were spinal cord ischemia, postoperative cranial nerve injury (CNI), and Horner's syndrome.

RESULTS

Seventeen patients underwent aLVA to carotid transposition as an adjunct to management of aortic disease during the study period. Most were men (14) and the mean age was 54 (±16 years). The primary indication for aortic repair was dissection in 10, aneurysm in 6, and Kommerell diverticulum in 1. Nine patients underwent zone 2 TEVAR, seven received open total arch repair and there was one attempted total endovascular arch repair which was aborted due to unfavorable anatomy. Twelve transpositions were performed prior to or concomitant with planned aortic repair due to high-risk cerebrovascular anatomy (3 PICA termination, 6 dominant aLVA, 4 intracranial left vertebral artery stenosis), and two were performed postoperatively for treatment of type II endoleak. LVA diameter ranged from 2 - 6mm (mean 3.3 mm). Mean operative time for transposition was 178 (±38) minutes, inclusive of left subclavian artery revascularization and mean estimated blood loss was 169 (±188) mL. No patients experienced 30-day postoperative spinal cord ischemia, stroke, or mortality. There were two cases of postoperative hoarseness, presumably due to recurrent laryngeal nerve palsy, both of which resolved within 4 months. There were no cases of Horner's syndrome. At follow-up (mean 306 days [6-714 days]), all transpositions were patent.

CONCLUSIONS

Vertebral-carotid transposition is a safe and effective adjunct in the management of aortic disease with anomalous origin of the LVA.

Model-Based Fluid-Structure Interaction Approach for Evaluation of Thoracic Endovascular Aortic Repair Endograft Length in Type B Aortic Dissection

Thoracic endovascular aortic repair (TEVAR) is a commonly performed operation for patients with type B aortic dissection (TBAD). The goal of TEVAR is to cover the proximal entry tear between the true lumen (TL) and the false lumen (FL) with an endograft to induce FL thrombosis, allow for aortic healing, and decrease the risk of aortic aneurysm and rupture. While TEVAR has shown promising outcomes, it can also result in devastating complications including stroke, spinal cord ischemia resulting in paralysis, as well as long-term heart failure, so treatment remains controversial. Similarly, the biomechanical impact of aortic endograft implantation and the hemodynamic impact of endograft design parameters such as length are not well-understood. In this study, a fluid-structure interaction (FSI) computational fluid dynamics (CFD) approach was used based on the immersed boundary and Lattice–Boltzmann method to investigate the association between the endograft length and hemodynamic variables inside the TL and FL. The physiological accuracy of the model was evaluated by comparing simulation results with the true pressure waveform measurements taken during a live TEVAR operation for TBAD. The results demonstrate a non-linear trend towards increased FL flow reversal as the endograft length increases but also increased left ventricular pulsatile workload. These findings suggest a medium-length endograft may be optimal by achieving FL flow reversal and thus FL thrombosis, while minimizing the extra load on the left ventricle. These results also verify that a reduction in heart rate with medical therapy contributes favorably to FL flow reversal.

Homemade fenestrated physician-modified stent-grafts for arch aortic degenerative aneurysms

OBJECTIVE

To evaluate early and medium-term outcomes of single and double fenestrated physician-modified endovascular grafts (PMEGs) for total endovascular degenerative aortic arch aneurysm repair.

METHODS

This single-center retrospective analysis of prospectively collected data included 52 patients, from August 2013 through January 2021, undergoing home-made fenestrated thoracic endovascular aortic repair (TEVAR) for degenerative aortic aneurysms. In all cases a distal smaller fenestration for the left subclavian artery (LSA) was fashioned and the only one stented. For double-fenestrated endograft a proximal larger fenestration that incorporated both the brachiocephalic trunk and left common carotid artery was added.

RESULTS

52 patients with degenerative aortic arch aneurysms were treated. There were 36 men and the mean age was 75 ± 8 years. 31% treated with a single LSA fenestration, while 69% had a double-fenestrated TEVAR. 10% (n=5) were emergent procedures. Technical success was 100%. The median time requirement for stent graft modification was 22 ± 6 minutes. Thirty-day mortality was 2% (n=1). 5 patients (10%) had a cerebrovascular event including 2 transient ischemic attack, one minor stroke with full neurological recovery and 2 with sequelae. 2 patients (4%) experienced perioperative retrograde dissection during follow-up. No patient had a type I, type III or type II endoleak from the LSA. No patient required re-intervention. All supra-aortic trunks were patent. During a mean follow up of 18 ± 11 months, there were no conversion to open surgical repair, aortic rupture or paraplegia.

CONCLUSIONS

Single or double PMEG is a safe and suitable tool for the treatment of high morbidity pathology such as aortic arch degenerative aneurysm repair. This device can be used in elective and emergency patients.

Early Results of a Novel Gutter-Free Chimney Stent-Graft System to Treat Aortic Arch Dissection: Single-Center Data from a Prospective Clinical Trial

AIMS

Discuss the clinical value, technique characteristics, and early follow-up results of a newly designed gutter-free chimney stent-graft system for aortic arch pathology.

METHODS AND RESULTS

About 13 patients with aortic arch dissection were enrolled in a clinical trial testing a novel gutter-free stent-graft between February 2019 and December 2020. All 13 patients were male, age 52.6±10.4 years. The implantation time was 14.0±6.9 minutes; total procedure time was 89.5±19.8 minutes. The volume of contrast was 79.6±7.2 ml. And 15 aortic stent-grafts were implanted, and all 13 patients had chimney branch stent-grafts implanted into the left subclavian artery (LSA). There were 3 (23.1%) cases of immediate type Ιa endoleak after thoracic endovascular aortic repair (TEVAR), and 7.7% type Ιa endoleaks occurred in delayed fashion. Survival at 2 years was 100%, and the 2-year patency of chimney stent-grafts was 100%.

CONCLUSIONS

This study reports early success with good freedom from endoleak using a novel stent-graft designed for chimney TEVAR to treat aortic arch dissection. Postoperative survival and patency of the branch stent-grafts were excellent. Additional data from this multicenter clinical trial will be forthcoming.

Anatomic feasibility of off-the-shelf thoracic single side-branched endograft in patients with blunt traumatic thoracic aortic injury

OBJECTIVE

The advent of thoracic single side-branched endograft (TSSBE) has provided a treatment option to obviate the need for open cervical debranching of the left subclavian artery (LSA), thereby enabling total endovascular incorporation of the LSA during thoracic endovascular aortic repair (TEVAR). In a previous study of patients with type B aortic dissection who had required zone 2 TEVAR, the anatomic feasibility of this device was demonstrated to range from 28% to 35%, suggesting limited applicability of the currently available designs. The objectives of the present study were twofold: (1) to evaluate the anatomic feasibility of TSSBE in blunt traumatic thoracic aortic injury (BTAI) patients who would require LSA revascularization; and (2) to describe the anatomic characteristics of the supra-aortic arch branches that could be used to improve future device design.

METHODS

A retrospective review was performed of BTAI patients who had undergone TEVAR at a single institution from November 2013 to October 2018. Preoperative computed tomography angiograms were analyzed using three-dimensional reconstruction to quantify the aortic diameter, distance and arc length between branch vessels, and the LSA diameter and length. We calculated the proportion of patients who had met all aortic and LSA anatomic requirements for TSSBE proposed by investigational protocols. We also assessed the effect of anatomic requirement modifications on device suitability. Finally, we assessed the local anatomic relationship between the supra-aortic branches.

RESULTS

A total of 41 patients (63% men; median age, 39 years; range, 23-88 years; 68% normal aortic arch pattern, 32% bovine aortic arch pattern) with BTAI who had required TEVAR involving the LSA and were, thus, considered potential candidates for TSSBE were included. Of the 41 patients, 13 (32%; 7 with a bovine aortic arch and 6 with a normal aortic arch) had met all proposed aortic and LSA anatomic requirements for TSSBE. An appropriate aortic diameter, LSA diameter, and LSA length to its first branch were observed in 100%, 95%, and 66% of the patients, respectively. An insufficient distance between the arch branch vessels, observed in 41%, was the most common exclusionary criterion. The median clock-face position of the LSA was 12:00 (interquartile range, 30 minutes) in the normal arch group and 11:45 (interquartile range, 15 minutes) in the bovine arch group.

CONCLUSIONS

Despite the numerous potential advantages of TSSBE, only 32% of patients with BTAI requiring LSA revascularization had met all the aortic and LSA anatomic requirements, justifying the need for additional designs. Better characterization and mapping of the aortic arch branches will improve future device design and application.

Endovascular Repair for Acute Type B Aortic Dissection With Unfavorable Proximal Landing Zone

BACKGROUND

The study aimed to compare the safety and effectiveness between fenestrated technique with or without chimney stent and single-branched stent graft for isolated left subclavian artery revascularization during endovascular repair of acute type B aortic dissection with unfavorable proximal landing zone.

METHODS

From January 2016 to December 2019, 65 acute type B aortic dissection patients with unfavorable proximal landing zone were treated with either the fenestrated technique (n = 34, group A) or single-branched stent graft (n = 31, group B). Type I endoleak, retrograde type A dissection, stroke, left subclavian artery patency, 30-day mortality, and aortic remodeling were systematically recorded and retrospectively analyzed.

RESULTS

Technical success rates for groups A and group B were 94.12% and 100%, respectively. Left subclavian artery primary patency was achieved for all enrolled patients. The incidence of type I endoleak, retrograde type A dissection, stroke, and 30-day mortality was 5.9%, 5.9%, 2.9%, and 2.9% in group A, respectively, but none were encountered in group B. Left subclavian artery occlusion was observed in 3 patients in group A and 2 patients in group B during a mean follow-up of 16.18 ± 2.08 months and 15.19 ± 2.68 months, respectively. After the procedure, significant aortic remodeling was detected in both groups during follow-up.

CONCLUSIONS

Both techniques are feasible and safe for isolated left subclavian artery revascularization during endovascular repair for acute type B aortic dissection. Apart from the associated perioperative risks of complications and mortality for the fenestrated technique, both procedures contributed to favorable aortic remodeling.

One-Year Single-Center Results of the Multilayer Flow Modulator Stents for the Treatment of Type B Aortic Dissection

Purpose

To report a single-center series of patients with type B aortic dissection treated with the Multilayer Flow Modulator (MFM).

Materials and Methods

Over a 36-month period, 23 patients (median age 53 years; 20 men) with complicated type B aortic dissections (2 acute, 5 subacute, and 16 chronic) were treated with the MFM. Primary endpoints of rupture or dissection-related death, overall mortality, and reintervention were evaluated using the Kaplan-Meier method; estimates for freedom from the endpoints are reported with the 95% confidence interval (CI). Secondary outcomes included technical success, adverse events, and aortic remodeling. Clinical and imaging data were collected preoperatively, directly postoperatively, and annually to 36 months for analysis using computational fluid dynamics (CFD).

Results

Initial technical success was 91.3%. The estimates of the endpoints at 12 months were 100% for freedom from rupture or aortic-related death, 95.7% for freedom from overall mortality, and 91.3% for freedom from reintervention. No device-related neurological or systemic complications occurred, and no additional reinterventions were needed during follow-up. A total of 144 branches overstented by the MFM remained patent. Morphologic analysis of the aortic dissection showed progressive true lumen volume increase (75.9%, p<0.001) with concomitant false lumen volume decrease (42.8%, p<0.001); the CFD analyses showed increased laminar flow.

Conclusion

In the current series, the MFM provided a safe and feasible treatment option for complicated acute, subacute, and chronic type B aortic dissections, with high technical success, low mortality, and active aortic remodeling. Further studies should elucidate the long-term safety of the MFM and its effectiveness in a larger patient cohort.

Anatomical Suitability of the Aortic Arch Arteries for a 3-Inner-Branch Arch Endograft

PURPOSE

To analyze aortic arch anatomy of patients who were already treated with a 2-inner-branch arch endograft (2-IBAE) in order to assess the anatomical suitability of the supra-aortic arteries as target vessels for a 3-IBAE.

MATERIALS AND METHODS

Three different configurations of the Cook Zenith Arch endograft were designed with distances of 110 mm (model 1), 90 mm (model 2), and 70 mm (model 3) between the orifices of the first and third inner branches. Preoperative measurements of the aortic arch anatomy from 104 consecutive patients treated electively with custom-made 2-IBAEs at 2 European centers between 2014 and 2019 were analyzed. A previously described standard methodology with a planning sheet was used. Data and measurements included the treatment indication for the aortic arch pathology, the type of landing zone, the type of arch, and the inner and outer lengths of the ascending aorta from the sinotubular junction to the innominate artery (IA). Additionally, the diameters and clock positions of the IA, left common carotid artery (LCCA), and left subclavian artery (LSA) were assessed, along with the distances between the IA and the LCCA, the IA and the LSA, and the distal landing zone.

RESULTS

Type I was the most common arch configuration (75/104, 72%). The mean clock positions were 12:30±00:28 for the IA, 12:00±00:23 for the LCCA, and 12:15±00:29 for the LSA. The mean diameters were 14.2±2.2 mm for the IA, 8.8±1.8 mm for the LCCA, and 10.5±2 mm for the LSA. The mean distances between the IA and LCCA and between the IA and LSA were 14.7±5.8 mm and 33±9.4 mm, respectively. Model 2 (branch distance 90 mm) had the highest suitability (79%), while models 1 and 3 showed suitability rates of 73% and 68%, respectively. The most frequent exclusion criterion in all models was the diameter of the LSA, followed by the IA to LSA distance.

CONCLUSION

The suitability for a 3-IBAE among patients who had a 2-IBAE implanted is high, favoring a 90-mm distance between the retrograde LSA branch and baseline.

Aneurysms and dissections - What is new in the literature of 2019/2020 - a European Society of Vascular Medicine annual review

More than 6,000 publications were found in PubMed concerning aneurysms and dissections, including those Epub ahead of print in 2019, printed in 2020. Among those publications 327 were selected and considered of particular interest.

Periscope sandwich stenting as an alternative to open cervical revascularization of left subclavian artery during zone 2 thoracic endovascular aortic repair

OBJECTIVE

Revascularization of the left subclavian artery (LSA) during zone 2 thoracic endovascular aortic repair (TEVAR) maintains collateral circulation to decrease ischemic complications, including stroke, spinal cord ischemia, and upper extremity ischemia. Both open surgical and endovascular LSA revascularization techniques have been described, each with unique risks and benefits. We describe our "periscope sandwich" technique for the LSA during zone 2 TEVAR, which maintains antegrade access to the distal abdominal aorta if subsequent interventions are necessary. Technical results and short-term outcomes are compared with LSA open surgical debranching.

METHODS

A single-institution retrospective review was performed for patients requiring zone 2 TEVAR with LSA revascularization by periscope sandwich technique or open surgical debranching with subclavian to carotid transposition (SCT) or carotid-subclavian bypass (CSB). The presenting aortic disease and perioperative details were recorded. Intraoperative angiography and postoperative computed tomography images were reviewed for occurrence of endoleak and branch patency.

RESULTS

Between January 2013 and December 2018, the LSA was revascularized by periscope sandwich in 18 patients, SCT in 22 patients, and CSB in 13 patients. Compared with open surgical debranching, periscope sandwich had a lower median estimated blood loss (100 mL vs 200 mL for pooled SCT and CSB; P = .03) and lower median case duration (133.5 minutes vs 226 minutes; P < .001). Contrast material volume (120 mL vs 120 mL; P = .98) and fluoroscopy time (13.1 minutes vs 13.3 minutes; P = .92) did not differ significantly between the groups. There was no difference in aorta-related mortality (P = .14), and LSA patency was 100%. Median follow-up for the periscope sandwich group was 11 months, with an overall estimated 91% freedom from gutter leak at 6 months.

CONCLUSIONS

LSA periscope sandwich technique provides safe and effective LSA revascularization during zone 2 TEVAR. LSA periscope sandwich can be used emergently with off-the-shelf endovascular components and facilitates future branched-fenestrated endovascular repair of thoracoabdominal aortic diseases.

Off-the-Shelf Devices for Treatment of Thoracic Aortic Diseases: Midterm Follow-up of TEVAR With Chimneys or Physician-Made Fenestrations

Purpose: To evaluate the midterm outcomes of thoracic endovascular aortic repair (TEVAR) using chimney grafts (ch-TEVAR) or thoracic stent-grafts with fenestrations made on the back table (f-TEVAR) to treat thoracic aortic dissection (TAD) and thoracic aortic aneurysm (TAA). Materials and Methods: A retrospective analysis was conducted of 474 consecutive patients (mean age 62.3±10.7 years; 346 men) treated with either f-TEVAR (n=110) or ch-TEVAR (n=364) for 352 TADs (81 f-TEVAR and 271 ch-TEVAR) or 122 TAAs (29 f-TEVAR and 93 ch-TEVAR) from 2008 to 2016. The primary endpoints at 30 days and during follow-up were overall mortality, aorta-related mortality, and major complications. The secondary endpoints were endoleak and reintervention. The patency of the target branches, cost of hospitalization, and the use of antiplatelet drugs were also analyzed. Results: Intraoperative type I endoleaks were treated in 69 (14.6%) cases (4 f-TEVAR and 65 ch-TEVAR, p<0.01) to achieve 100% technical success. Four (0.8%) patients died within 30 days [1 (0.9%) f-TEVAR and 3 (0.8%) ch-TEVAR]. Perioperative cerebral ischemia (1 fatal stroke) occurred in 9 (1.9%) patients: (1 f-TEVAR and 8 ch-TEVAR, p=0.39). During the mean follow-up of 50.6±20.0 months (49.5±18.3 months in f-TEVAR and 50.9±20.6 months in ch-TEVAR), 11 (2.3%) patients died of an aorta-related event. Type I endoleak was present in 40 (8.4%) patients (1 f-TEVAR and 39 ch-TEVAR, p<0.01). Eleven (2.3%) patients experienced stent-graft migration and 13 (2.7%) had a retrograde dissection. One hundred (16.9%) of the 593 branch stents occluded (4/75 in the f-TEVAR group and 96/518 in the ch-TEVAR group, p<0.01). The branch reintervention rate was 7.2% (34/474). The f-TEVAR group had a significantly higher probability of freedom from branch occlusion (92%) than the ch-TEVAR group (83%, p=0.007). Conclusion: Off-the-shelf techniques employing chimney grafts and homemade fenestrations are both suitable options for TAD and TAA involving the supra-aortic branches, with a low incidence of reintervention. Fenestrated TEVAR seems to have more favorable short- and midterm outcomes. Further study of these off-the-shelf techniques for aortic arch repair is warranted.