Technical challenges in endovascular repair of complex thoracic aortic aneurysms

Fenestrated Thoracic Endovascular Repair for Acute Type B Aortic Dissection with Isolated Left Vertebral Artery: A Case Report

Thoracic endovascular aortic repair (TEVAR) of acute uncomplicated type B aortic dissection (uTBAD) has been discussed for its potential to prevent future aortic events. We present a fenestrated TEVAR in the case of an 86-year-old man with acute uTBAD with an isolated left vertebral artery (ILVA). The ILVA originated from the distal side of the left subclavian artery, the left subclavian artery, and the intramural hematoma with an ulcer-like projection extended close to the left subclavian artery. We selected a fenestrated stent graft to achieve a proximal healthy landing. This case demonstrates that a fenestrated stent graft for acute uTBAD is useful for preserving arch vessels.

Image fusion guidance for left subclavian artery in situ fenestration during thoracic endovascular repair

OBJECTIVES

To evaluate the feasibility and clinical benefit of utilizing image fusion for thoracic endovascular repair (TEVAR) with in situ fenestration (ISF-TEVAR).

MATERIALS AND METHODS

Between January 2020 and December 2020, we prospectively collected 18 consecutive cases with complex thoracic aortic lesions who underwent image fusion guided ISF-TEVAR. As a control group, 18 patients were collected from historical medical records from June 2019 to December 2019. The fusion group involved the use of 3D fusion of CTA and fluoroscopic images for real-time 3D guidance, and the control group involved the use of only regular fluoroscopic images for guidance. The total contrast medium volume, hand-injected contrast medium volume, overall operative time, radiation dose and fluoroscopy time were compared between the two groups. Accuracy was measured based on preoperative CTA and intraoperative digital subtraction angiography.

RESULTS

3D fusion imaging guidance was successfully implemented in all patients in the fusion group. Hand-injected contrast medium volume and overall operative time were significantly lower in the fusion group than in the control group (p = .028 and p = .011). Compared with the control group, the fusion group showed a significant reduction in time and radiation dose-area product (DAP) for fluoroscopy (p = .004 and p = .010). No significant differences in total radiation dose (DAP) or total contrast medium volume were observed (p = .079 and p = .443). Full accuracy was achieved in 8 cases (44%), with a mean deviation of 2.61 mm ± 3.1 (range 0.0-8.4 mm).

CONCLUSIONS

3D image fusion for ISF-TEVAR was associated with a significant reduction in hand-injected contrast medium, time and radiation exposure for fluoroscopy and overall operative time. The image fusion guidance showed potential clinical benefits towards improved treatment safety and accuracy for complex thoracic endovascular interventions.

Preemptive fenestrated endovascular repair aimed at perfusion of cervical branches in acute type B aortic dissection

OBJECTIVE

Most of the entry tears of uncomplicated type B aortic dissection are located in the distal arch and extends in a retrograde manner to the level of the left subclavian artery. Our objective was to evaluate feasibility and effectiveness using fenestrated sent graft with complete neck vessel preservation to treat uncomplicated type B aortic dissection.

SUBJECTS AND METHODS

We retrospectively reviewed the record of patients with uncomplicated type B aortic dissection who underwent fenestrated thoracic endovascular aortic repair in subacute phase (15-90 days) between August 2016 and April 2020. The Najuta fenestrated stent graft was placed proximally beyond he left subclavian artery (zone 0-2) in an attempt to seal the entry while preserving the neck vessels.

RESULTS

We evaluated 9 cases (male: 7, female: 2; median age 70 years). The median distance from the LSA to the proximal entry was 37 mm. The landing zones of the proximal end of the Najuta were zone 0: 3, zone 1: 2, and zone 2: 4 cases. Technical success was 100% with no 30-day death. None of the patients had a stroke, paraplegia or retrograde dissection, and no endoleak was observed. Complete aortic remodeling with false lumen resolution was obtained in all cases while each fenestrated vessels remained patent during the follow-up period.

CONCLUSION

Preemptive thoracic endovascular aortic repair aimed at perfusion of cervical branches using the Najuta fenestrated stent is safe and effective and may be considered as a reasonable treatment option for the treatment is a safe and an effective treatment.

An autopsy case of retrograde in situ branched stent grafting for a complex aortic arch aneurysm

Although retrograde in situ branched stent grafting (RIBS) is one possible treatment option for thoracic aortic aneurysms, concerns exist regarding the durability of the stent graft (SG) at the junction between the main SG and the branched SG. We report on the autopsy results of a patient treated with RIBS for a complex aortic arch aneurysm. The patient had died of a nonaortic cause 14 months after the RIBS procedure. On computed tomography analysis and a leak test, the harvested SG was intact without any stent fracture, stenosis, or junctional leak at 1 atm water pressure (760 mm Hg).

Complete neck vessel preservation using a fenestrated stent graft for the treatment of proximal anastomotic leakage after open frozen elephant trunk graft aortic arch repair

We have reported a case of proximal anastomotic leakage excluded with the Najuta fenestrated stent graft after a surgeon-modified frozen elephant trunk aortic arch graft. The fenestrated stent graft was deployed at the zone 0 proximal site, preserving the cervical branches. Complete neck vessel preservation during endovascular repair using a Najuta fenestrated stent graft appears to be safe and effective for anastomotic leakage after aortic arch aneurysm repair.

Total Debranching Plus Antegrade Thoracic Endovascular Aortic Repair without Side Clamping in a Patient with Arch Aneurysm and Ascending Aorta Calcification

A high-risk patient with aortic arch aneurysm, associated with severe calcification of the ascending aorta and iliac arteries, was treated with total debranching and antegrade thoracic endovascular aortic repair (TEVAR) via the ascending aorta. Proximal anastomosis for a triple-branched graft to the ascending aorta was performed without side clamping using the "real chimney technique." After bypassing the supra-aortic branches, a TEVAR was performed in an antegrade fashion through the ascending aorta. This case suggests that the approaches mentioned above should be considered in patients with arch aneurysms and severe calcified degeneration.

Marmoset angiography just by percutaneous puncture of the caudal ventral artery

Surgery in humans is continuously evolving and promoted minimally invasive treatment. On the other hand, despite the importance of the 3Rs principles for experimental animals is well documented, no reports describe specific methodologies for implementing "refinement" in practice. Here, we describe a new technique, the "Ohta Method" for caudal arthrocentesis in the pursuit of the 3Rs for animal experiments and the development of innovative methods for investigating systemic organ arteries through minimally invasive procedures. This procedure requires only a percutaneous puncture of the caudal artery without any injury to the limb or body trunk. In addition, it does not cut down the artery, making hemostasis easier and recovering arterial damage easier. We will show multiple organ artery angiographies in marmoset for the first time in the world. The principle described in this paper could also be applied to many other small animals, such as rats. Moreover, using this method, multiple doses of the drug or cells can be administered to the target organ at the time of therapeutic intervention, thereby enabling the establishment of more sophisticated and complex therapeutic intervention studies as translational research.

The lift snorkel technique for type Ia endoleak after fenestrated endovascular aneurysm repair of a juxtarenal abdominal aortic aneurysm

Background

The snorkel technique for a juxtarenal abdominal aortic aneurysm (JAAA) is an important treatment option for high-risk patients. We report the lift snorkel technique through the trans-femoral access for a type Ia endoleak after fenestrated endovascular aneurysm repair (FEVAR) in a case of difficult trans-brachial access.

Case presentation

A 76-year-old woman who had JAAA presented with a type Ia endoleak and sac expansion after FEVAR. We planned for proximal additional stentgraft with the bilateral renal artery snorkel technique. However, during the secondary intervention, it was difficult to cannulate to the left renal artery through the trans-brachial access due to interference of the supra-renal stent. Stentgraft was eventually delivered into the left renal artery via the trans-femoral access with a 5 Fr sheath. A plain angioplasty balloon was inserted coaxially through the sheath. The balloon was inflated in the proximal end of the stentgraft and then pushed up to replace the proximal end from down to up. The additional aortic cuff was deployed parallel to the snorkel stentgraft. One year after the additional treatment, computed tomography (CT) revealed aneurysm sac shrinkage.

Conclusion

The lift snorkel technique is a unique method converting the retrograde approach to antegrade renal artery stenting and would be an effective option for difficult trans-brachial cases for a type Ia endoleak after FEVAR of a JAAA.

Long-Term Outcomes after Thoracic Endovascular Aortic Repair Using Chimney Grafts for Aortic Arch Pathologies: 10 Years of Single-Center Experience

BACKGROUND

This study reports the early- and long-term outcomes of the thoracic endovascular aortic repair using the Chimney-Graft technique (ChTEVAR) for the treatment of aortic arch pathologies.

METHODS

From January 2010 to December 2019, patients who underwent aortic ChTEVAR technique in our institution were included. Early, mid, and long-term outcomes in this group of patients were evaluated. Patient follow-up data were obtained by imaging follow-up that are routinely performed after 3-6 months following initial surgery and then at yearly intervals.

RESULTS

Aortic arch repair with a ChTEVAR was performed in 54 patients. The 30-day mortality was 18.5% (n = 10). All-cause 30-day mortality was higher in the subgroup of patients operated urgently (33% vs. 14%) without a significant difference (P = 0.141). Permanent neurological deficit (PND) was observed in 15% (8/54 patients); stroke in 11% (6/54), and paraplegia 4% (2/54). During follow-up the primary and primary-assisted chimney-graft patency was 96.8% and 97.8%, respectively. The multivariate analysis identified the age >70 years and the aortic diameter as independent risk factors for elevated mortality during the follow-up (P = 0.015 and 0.001, respectively). The PND was an independent predictor for 30-day mortality (P = 0.014, hazard ratio 13.5, 95% confidence interval 1.7-106.6).

CONCLUSIONS

The ChTEVAR has noninferior results to other open and endovascular aortic arch repair methods with an acceptable long-term survival especially in elective procedures.

Aortic Wall Enhancement Detected by Contrast Computed Tomography Scan Predicts Aortic Remodeling after Conservative Therapy for Acute Uncomplicated Type B Dissection

BACKGROUND

The Investigation of Stent Grafts in Aortic Dissection with extended length of follow-up trial showed that pre-emptive thoracic endovascular aneurysm repair (TEVAR) for the uncomplicated type B dissection (TBAD) in the subacute phase promotes aortic remodeling and avoids aortic-related death 5 years after onset. However, there are some patients with complete aortic remodeling (CAR) with optimal medical treatment (OMT) and severe complications after TEVAR such as retrograde type A dissection. Therefore, which patients should undergo pre-emptive TEVAR and optimal surgical timing are still under debate. We reported that aortic wall enhancement (AWE) after endovascular aneurysm repair for abdominal aortic aneurysm was associated with sac shrinkage. However, there is no report about the relationship between AWE and aortic dissection. Herein, we evaluated the relationship between AWE and acute TBAD.

METHODS

From March 2012 to May 2018, consecutive patients with acute TBAD were retrospectively collected. We retrospectively analyzed 35 patients with acute TBAD who were treated with OMT and without pre-emptive TEVAR in the subacute phase. AWE was defined as an increase of more than 20 Hounsfield units in mean computed tomography (CT) values, comparing images in delayed contrast-enhanced scans with those in plain scans evaluated within 3 months from onset. The measurement points were all slices including the wall of the false lumen. The patients with traumatic dissection, type A dissection, acute complicated type B dissection, chronic (>12 weeks) dissection, and those lost to follow-up within 3 months from onset were excluded. The primary end point was spontaneous CAR under OMT, as determined by the latest contrast-enhanced CT scan.

RESULTS

The median follow-up period from onset was 86 weeks and there were 25 cases (71.4%) with AWE. Under OMT, CAR was observed in 20 patients (57.1%); this was significantly associated with abdominal branch dissection (6/15 [40%] vs. 2/20 [10%], P = 0.050), number of tears more than 2 at onset (11/15 [73%] vs. 4/20 [20%], P = 0.003), multiple tears at 1 month after onset (9/15 [60%] vs. 4/20 [20%], P = 0.020), maximal false lumen diameter at 1 month after onset (14 vs. 8 mm, P = 0.025), and AWE within 3 months of onset (7/15 [47%] vs. 18/20 [90%], P = 0.010). Multivariate analysis demonstrated a significant difference with multiple tears at onset (P = 0.014) and AWE within 3 months of onset (P = 0.047).

CONCLUSIONS

AWE was associated with CAR under OMT for acute TBAD which is out of indication of pre-emptive TEVAR. Presence of AWE may be useful in predicting prognosis of TBAD.

Spontaneous ruptured aortic plaque and injuries: insights for aging and acute aortic syndrome from non-obstructive general angioscopy

Recent advances in non-obstructive general angioscopy (NOGA) have enabled the detection of aortic atherosclerosis. The incidence of spontaneous ruptured aortic plaques (SRAPs) and aortic injuries was found to be high in patients diagnosed with or suspected of having coronary artery disease. These facts may result in a paradigm shift for diseases such as aging and acute aortic syndrome because the incidence of systemic embolic diseases and aortic disease are assumed be high. Aortic thromboembolism has been thought to be mainly iatrogenic and is referred to as "cholesterol embolization syndrome" or "cholesterol crystal embolization", although the cholesterol crystals (CCs) were not demonstrated routinely as real images. Atheromatous materials, fibrins, calcifications, macrophages, and a mixture of such substances are released through a puff or puff-chandelier rupture. Among atheromatous materials, CCs can be easily detected clinically in sampled blood via polarized light microscopy. Atheromatous materials include rich CCs and free monolayers, and multilayer CCs are released when the atheromatous materials from vulnerable plaques break into pieces, such as in puff or puff-chandelier rupture. Released SRAPs seem to be asymptomatic; however, accumulation of SRAPs referred to as accumulated spontaneous asymptomatic plaques may cause aging through systemic "embolic" processes, such as mechanical obstruction and an inflammasome pathway. Unique findings in "atherosclerotic" acute aortic syndrome, such as a clear boundary between the dissected lesion and the normal lesion, fissure/fissure bleeding suggesting an entry or a reentry, and subintimal blood flow detected through NOGA are reported. Fissure/fissure bleeding and subintimal blood flow may be the first or last triggers of "atherosclerotic" acute aortic syndrome. Pre-emptive diagnosis and risk stratification of acute "atherosclerotic" aortic dissection and feedback for endovascular therapy may be enabled through the use of NOGA in the future.

Exogenous Vasohibin-2 Exacerbates Angiotensin II-Induced Ascending Aortic Dilation in Mice

Background: Chronic angiotensin II (AngII) infusion promotes ascending aortic dilation in C57BL/6J mice. Meanwhile, vasohibin-2 (VASH2) is an angiogenesis promoter in neovascularization under various pathologic conditions. The aim of this study was to investigate whether exogenous VASH2 influences chronic AngII-induced ascending aortic dilation.

Methods and Results: Eight–ten-week-old male C57BL/6J mice were injected with adenovirus (Ad) expressing either VASH2 or LacZ. One week after the injection, mice were infused with either AngII or saline s.c. for 3 weeks. Mice were divided into 4 groups: AngII+VASH2, AngII+LacZ, saline+VASH2, and saline+LacZ. Overexpression of VASH2 significantly increased AngII-induced intimal areas as well as the external diameter of the ascending aorta. In addition, VASH2 overexpression promoted ascending aortic medial elastin fragmentation in AngII-infused mice, which was associated with increased matrix metalloproteinase activity and medial smooth muscle cell (SMC) apoptosis. On western blot analysis, accumulation of apoptotic signaling proteins, p21 and p53 was increased in the AngII+VASH2 group. Furthermore, transfection of human aortic SMC with Ad VASH2 increased p21 and p53 protein abundance upon AngII stimulation. Positive TUNEL staining was also detected in the same group of the human aortic SMC.

Conclusions: Exogenous VASH2 exacerbates AngII-induced ascending aortic dilation in vivo, which is associated with increased medial apoptosis and elastin fragmentation.

Two Wire System and Modified Olive Tip to Facilitate Implantation of Fenestrated TEVAR in Patient with Proximal Descending Aortic Pathology: First Two Cases

Introduction

Although Fenestrated TEVAR (F-TEVAR) has been considered to be a more physiologic approach to treat proximal descending aortic pathology, its application is still limited due to availability, cost and technical difficulties. We introduce a new design of fenestrated stent graft with a new delivery system and successfully performed first in human implantation in two patients, one with an aortic aneurysm and one with an acute aortic dissection.

Materials and Methods

The design of these two wires fenestrated stent graft include creation of an additional lumen at the side of the olive tip during manufacture, from which an additional wire can be introduced for a side branch passing into the fenestration, running inside the stent graft and exit the delivery sheath through additional hub. The two wires will facilitate delivery and deployment of the stent graft. One patient with descending aortic aneurysm and another with Stanford B aortic dissection is included in this first in human study.

Results

The aneurysm and dissection were completely excluded immediately after the TEVAR. Six month follow up CT showed good position of the stent graft and patent LSA in both patients. In the patient with aortic dissection, expansion of the true lumen and partial thrombosis of the false lumen was seen.

Conclusions

This is a report of a two wire system in 2 patients with distal aortic arch pathology demonstrating a good technical and clinical success using pre-cannulated fenestrations through a modified nose cone olive.

Level of Evidence

Level 4, report of two cases.

Antegrade thoracic endovascular aortic repair using an ascending aortofemoral through-and-through wire technique for a severely tortuous aorta associated with rickets

Background

Severe aortic tortuosity of the access route often prevents successful complete exclusion of an aneurysm in thoracic endovascular aortic repair (TEVAR).

Case presentation

We performed antegrade TEVAR on a 79-year-old man with right hemiparesis. We deployed the stent graft from the ascending aorta with a tube graft conduit to treat a descending thoracic aortic aneurysm associated with rickets and multiple comorbidities. Although the application of a ministernotomy diminished the potential advantages of endovascular treatment in view of less invasive surgery, antegrade TEVAR using an ascending aortofemoral through-and-through wire technique was a good option in this patient because a conventional retrograde approach was not feasible due to his severely tortuous aorta.

Conclusions

To avoid device-related complications, it is crucial to make a prudent preoperative decision on a patient-by-patient basis, taking into account the appropriate access site, adjuvant guidewire technique, and adjunctive surgical interventions.

Multivariate Analysis of Risk Factors of Cerebral Infarction in 439 Patients Undergoing Thoracic Endovascular Aneurysm Repair

The aim of the study is to identify the potential risk factors of cerebral infarction associated with thoracic endovascular aneurysm repair (TEVAR). TEVAR was developed as a less invasive surgical alternative to conventional open repair for thoracic aortic aneurysm treatment. However, outcomes following TEVAR of aortic and distal arch aneurysms remain suboptimal. Cerebral infarction is a major concern during the perioperative period. We included 439 patients who underwent TEVAR of aortic aneurysms at a high-volume teaching hospital between July 2006 and June 2013. Univariate and multivariate logistic regression analyses were performed to identify perioperative cerebral infarction risk factors. Four patients (0.9%) died within 30 days of TEVAR; 17 (3.9%) developed cerebral infarction. In univariate analysis, history of ischemic heart disease and cerebral infarction and concomitant cerebrovascular disease were significantly associated with cerebral infarction. "Shaggy aorta" presence, left subclavian artery coverage, carotid artery debranching, and pull-through wire use were identified as independent risk factors of cerebral infarction. In multivariate analysis, history of ischemic heart disease (odds ratio [OR] 6.49, P = 0.046) and cerebral infarction (OR 43.74, P = 0.031), "shaggy aorta" (OR 30.32, P < 0.001), pull-through wire use during surgery (OR 7.196, P = 0.014), and intraoperative blood loss ≥800 mL (OR 24.31, P = 0.017) were found to be independent risk factors of cerebral infarction. This study identified patient- and procedure-related risk factors of cerebral infarction following TEVAR. These results indicate that patient outcomes could be improved through the identification and management of procedure-related risk factors.

Aortic arch aneurysm repair using the Najuta stent graft in a challenging compromised seal zone

We report the case of a 67-year-old patient with an anatomically complex aneurysm of the aortic arch treated by fenestrated thoracic endovascular aortic repair with subclavian-carotid extrathoracic bypass. We used the Najuta thoracic stent graft, which was approved for use in January 2013 in Japan and successfully excluded the aneurysm. Our case shows that the Najuta stent graft procedure is a feasible treatment if open repair is unsuitable for cases of aortic arch aneurysm with a challenging compromised seal zone.