Thoracic Stent Graft Research Articles

Female gender is associated with increased late luminal narrowing within the stent graft after thoracic endovascular aortic repair.

Luminal narrowing, suspected secondary to thrombus, occurs within stent grafts at an unclear incidence after thoracic endovascular aortic repair (TEVAR). The significance of this phenomenon has not been determined, nor have the risk factors for development of intragraft luminal narrowing. Small graft diameter is hypothesized to be a risk factor for the development of ingraft stenosis. A retrospective analysis was performed of a multicenter healthcare system including all patients who underwent TEVAR between July 2011 and July 2019 with at least 1year of subsequently available surveillance contrast-enhanced computed tomography imaging. Standard demographic, preoperative, intraoperative, and postoperative variables were collected. Measurements were obtained via direct off-line images from computed tomography scans. Patent intragraft diameters were compared with baseline and interval change values were normalized to time to follow-up. The primary outcome measure was annual rate of intragraft luminal narrowing. There were 208 patients who met the inclusion criteria (94 women, 114 men) with a median follow-up of 822days. The mean annual rate of percent intragraft diameter reduction was 10.5± 7.7% for women and 7.6± 5.6% for men (P= .0026). Multivariate analysis demonstrated female gender (P= .0283), preoperative diagnosis of hypertension (P= .0449), and need for coverage of the left subclavian artery (P= .0328) were all significant predictors of intragraft luminal narrowing. Small aortic diameters were not found to be associated independently with ingraft luminal narrowing nor was the concomitant use of antiplatelet or anticoagulation medications. Significant amounts of ingraft luminal narrowing, defined as a greater than 20% intragraft diameter decrease, were associated with an increased need for any reintervention, including for malperfusion, endoleak, and symptomatic aneurysm (P= .0249). Kaplan-Meier estimates demonstrated a significant gender-associated difference in high rates of intragraft luminal narrowing (P=.00189). In this analysis, female gender is shown to be a significant nonmodifiable risk factor for intragraft luminal narrowing after TEVAR. The development of this phenomenon is not benign; as such, these findings were associated with an increased need for reintervention. This finding may be attributable to differences in aortic compliance or gender-associated differences in coagulation pathways and merits further investigation. Surveillance after thoracic stent grafting must account for patient-specific variations in complication risk.

The extended PETTICOAT technique does not guarantee favorable remodeling after acute type B aortic dissection.

Favorable remodeling is not always observed after thoracic endovascular aortic repair (TEVAR) in acute complicated type B aortic dissection (TBAD). Existing distal re-entries might be the cause of that. Many more extensive techniques have been introduced and evaluated. None of them achieve proven benefit in long-term follow-up. A new technique called extended PETTICOAT (provisional extension to induce complete attachment) or e-PETTICOAT technique was published in 2018. It allows one to cover proximal and distal re-entries and consists of: combined implantation of a thoracic stent graft to seal the proximal entry; self-expandable stents in the visceral aorta to expand the true lumen; plus two parallel kissing iliac stent grafts below the renal arteries. Despite encouraging medium term results, it has unknown long-term consequences. The prospective observational single center study included 11 patients with complicated acute TBAD qualified for endovascular treatment using the e-PETTICOAT technique. Complicated acute TBAD was identified only in cases of clinical manifestation before or at the time of intervention; radiological findings were not sufficient to identify complications in our study. Method: The 5-year follow-up, based on clinical outcome including survival, re-interventions and angio-CT-assessed remodeling, was examined. The e-PETTICOAT technique achieves good remodeling in 38% of primary and 88% of secondary procedures. The E-PETTICOAT does not guarantee favorable remodeling during a 5-year follow-up in acute complicated TBAD. Complex aortic repair after e-PETTICOAT might be needed.

Reoperative repair of adult aortic coarctation with explantation of thoracic stent-graft: a case report

Reoperative repair of adult aortic coarctation with explantation of thoracic stent-graft: a case report

Time-resolved, Cardiac-gated Computed Tomography After Endovascular Ascending Aortic and Arch Repair

PurposeBetter time-resolved imaging of stent grafts in the ascending aorta and arch accounting for cardiac motion is necessary to understand device-related complications and endoleaks. This report describes dynamic time-resolved computed tomographic angiography (d-CTA) and its combination with electrocardiography gating (d-gated CTA) to image stent grafts in the ascending aorta and to characterize endoleaks more clearly. Descriptiond-CTA involves multiple scans acquired at different time points along the contrast enhancement curve. d-Gated CTA involves concomitant electrocardiography gating in a predefined cardiac phase minimizing motion-induced artifacts. EvaluationThis report illustrates the utility of d-CTA and d-gated CTA in 2 clinical cases. d-CTA demonstrated a type 1A endoleak in a patient with an aortic arch aneurysm treated with total arch debranching and a thoracic stent graft. d-gated CTA demonstrated a type 1A endoleak in a patient with an ascending aortic pseudoaneurysm treated with aortic cuff placement. ConclusionsDynamic, cardiac-gated CTA enables time-resolved angiographic imaging of the ascending aorta and arch without any cardiac motion–related artifacts. Such advanced imaging techniques help with better characterization of endoleaks after stent graft deployment in the ascending aorta and arch.

Radiation-Free Thoracic Endovascular Aneurysm Repair with Fiberoptic and Electromagnetic Guidance: A Phantom Study

PurposeTo evaluate the feasibility and accuracy of a radiation-free implantation of a thoracic aortic stent graft employing fiberoptic and electromagnetic tracking in an anthropomorphic phantom. Materials and MethodsAn anthropomorphic phantom was manufactured based on computed tomography (CT) angiography data from a patient. An aortic stent graft application system was equipped with a fiber Bragg gratings and 3 electromagnetic sensors. The stent graft was navigated in the phantom by 3 interventionalists using the tracking data generated by both technologies. One implantation procedure was performed. The technical success of the procedure was evaluated using digital subtraction angiography and CT angiography (before and after the intervention). Tracking accuracy was determined at various anatomical landmarks based on separately acquired fluoroscopic images. The mean/maximum errors were measured for the stent graft application system and the tip/end of the stent graft. ResultsThe procedure resulted in technical success with a mean error below 3 mm for the entire application system and <2 mm for the position of the tip of the stent graft. Navigation/implantation and handling of the device were rated sufficiently accurate and on par with comparable, routinely used stent graft application systems. ConclusionsThe study demonstrates successful stent graft implantation during a thoracic endovascular aortic repair procedure employing advanced guidance techniques and avoiding fluoroscopic imaging. This is an essential step in facilitating the implantation of stent grafts and reducing the health risks associated with ionizing radiation during endovascular procedures.

Explantation of a thoracic stent-graft with open repair of coarctation of the aorta via left lateral thoracotomy.

Explantation of a thoracic stent-graft with open repair of coarctation of the aorta via left lateral thoracotomy.

A RARE PRESENTATION OF THORACIC AORTIC ANEURYSM RUPTURE

TOPIC: Signs and Symptoms of Chest Diseases TYPE: Medical Student/Resident Case Reports INTRODUCTION: Thoracic aortic aneurysm (TAA) is an uncommon clinical condition, commonly associated with atherosclerosis. It is mostly asymptomatic but aneurysm exceeding 6 cm are at risk of yearly rate of rupture or dissection of at least 6.9% and a death rate of 11.8%. We present to you a case of TAA with rupture presenting with cough, hemoptysis and pneumonitis. CASE PRESENTATION: Patient is a 68 years male who presented to the ED with cough, hemoptysis, chest discomfort for 2-3 days. He had intermittent episodes of fever. COVID test was negative 3 days ago. Past medical history was significant for HTN, Asthma, COPD, Diabetes mellitus, tobacco use disorder. Patient was afebrile with BP of 137/73, HR 72, RR 16, O2 saturation of 89% in room air. Physical examination including chest was unremarkable. Initial workup including CBC was remarkable for WBC of 12500, Hgb of 10.5, INR 0.8, PTT 24, Troponin 5 cm, smokers, COPD, advanced age, hypertension. Thoracic endovascular stent graft surgery, under epidural anesthesia, is the preferred surgical treatment especially in old TAA patients as in our case because of low morbidity, mortality and hospital stay. CONCLUSIONS: Rupture of TAAs is still very rare, but should remain on the differential for a patient with cough, hemoptysis with features of pneumonitis as it is associated with very high morbidity and mortality rates. REFERENCE #1: CL F, Esk, MK ari. Thoracic endovascular aneurysm Repair (TEVAR) for Ruptured THORACIC aortic aneurysms. Published May 2, 2017 REFERENCE #2: Inam, H., Zahid, I., Khan, S.D. et al. Hemoptysis secondary to rupture of infected aortic aneurysm– a case report. J Cardiothorac Surg 14, 144 (2019). https://doi.org/10.1186/s13019-019-0959-y REFERENCE #3: Sun D, Mehta S. Hemoptysis caused by erosion of thoracic aortic aneurysm. CMAJ. 2010;182(4):E186. doi:10.1503/cmaj.090447 DISCLOSURES: No relevant relationships by Luna Khanal, source=Web Response No relevant relationships by Adarsha Ojha, source=Web Response

Transapical Antegrade Ascending Aorta Stent-Grafting: Going Through the Front Door.

Ascending aorta stent-grafting (AASG) is a new option that has shown initial promising results. In selected cases, when neither conventional surgery nor transfemoral retrograde approach are feasible, antegrade transapical (TA) access can be performed. The aim of this single-center retrospective study was to evaluate outcomes of patients undergoing AASG through a TA approach. We analyzed all patients undergoing AASG through a TA approach at our institution. Three different devices were used, including Relay Stent-Graft System (Terumo Aortic, UK), Gore Conformable Thoracic Aortic Graft (W. L. Gore & Associates, Inc., USA), and Valiant Thoracic Stent Graft (Medtronic, Ireland). All patients underwent clinical and computed tomographic angiogram (CTA) evaluation before hospital discharge. From May 2010 to December 2019, 3 consecutive patients underwent AASG at our institution. Mean age was 69 years. Three different types of endografts were used in 1 patient each. All patients stayed in the intensive care unit for 24 hr and mean hospital stay was 12 days. We did not observe any major adverse event. One patient died of pneumonia 2 months after the procedure and the other 2 patients are alive and in good clinical conditions at a mean follow-up of 56 months. Predischarge CTA showed good anatomic results with no endoleaks in all cases. This initial experience shows that AASG is feasible and provides encouraging clinical and anatomic results in selected high-risk patients.

Editor's Choice – Four Fenestration Endovascular Aortic Aneurysm Repair Without Stenting of the Coeliac Artery in Selected Cases

Editor's Choice – Four Fenestration Endovascular Aortic Aneurysm Repair Without Stenting of the Coeliac Artery in Selected Cases

Preoperative high lymphocyte-to-monocyte ratio is associated with intraoperative type I endoleak in patients with TAA with TEVAR.

Various inflammatory factors are closely associated with the incidence of thoracic aortic aneurysms (TAAs). Furthermore, the severity of inflammation is closely related to the absolute value and proportion of each leukocyte subgroup. Only few reports have analyzed the importance of lymphocyte-monocyte ratio (LMR) as a potential inflammatory marker in vascular diseases. Therefore, we aimed to investigate the effect of peripheral blood LMR on thoracic endovascular aortic repair (TEVAR) in patients with TAA. A retrospective study of the clinical data collected in our hospital between January 2016 and January 2021 was performed on 162 patients with TAA treated with TEVAR, based on the inclusion and exclusion criteria for patient selection. Based on whether the patient had the clinical symptoms at admission and the occurrence of type I endoleaks during operation, patients were divided into two groups, respectively: an intraoperative type I endoleak group (n = 34) and a group without intraoperative type I endoleak (n = 128), and a group with clinical symptoms (n = 31) and a group without clinical symptoms (n = 131). The clinical data of these two groups were compared, the free from second intervention rates related to endoleak and the preoperatively LMR of the two groups was calculated. LMR was calculated preoperatively. Receiver-operating characteristic curve analysis was used to determine the cut-off for preoperative LMR values. Based on the cut-off point, patients were divided into a high LMR group (n = 34) and a low LMR group (n = 128). The clinical data of the two groups were compared, and further stratified analysis was performed. A total of 162 patients were included in the analysis. All patients were successfully implanted with a thoracic aorta stent graft. The preoperative LMR level and postoperative endoleak-related secondary intervention rate were higher in the type I endoleak group than those in the group without intraoperative type I endoleaks. The preoperative C-reactive protein (CRP) level of patients with TAA with clinical symptoms was higher than that of asymptomatic patients. There was a negative correlation between preoperative CRP and LMR levels. In addition, in symptomatic or asymptomatic patients, the LMR level was associated with the occurrence of intraoperative type I endoleaks. After excluding the influence of type of endografts, our results showed that the clinical symptoms did not affect the occurrence of the intraoperative type I endoleak, and patients with intraoperative type I endoleak had a higher rate of postoperative secondary intervention. Patients with TAA with type I endoleaks during TEVAR had an increased rate of secondary intervention related to endoleaks. Patients with TAA with high LMR levels before TEVAR were more likely to have endoleaks during operation.

Outcome analysis of the Gore Conformable Thoracic Stent Graft with active control system for the treatment of arch and descending thoracic aortic disease

Abstract OBJECTIVES The aim of this study was to evaluate technical/clinical outcomes of the Gore TAG Conformable Thoracic Stent Graft with Active Control System (CTAG with ACS) in thoracic aortic disease since its introduction in Europe in 2017. METHODS Patients undergoing thoracic endovascular aortic repair (TEVAR) with the device between 2017 and 2020 were identified from a prospectively maintained single-centre database and retrospectively analysed. Predominant indications were aortic dissection (n = 46), thoracic/thoraco-abdominal aneurysm (n = 20/n = 7), penetrating ulcer (n = 14) and intramural haematoma (n = 12). Emergency procedures were performed in 47% (54/115). The primary outcome was technical success. Secondary outcomes were clinical success, serious adverse events and procedure-related reintervention. ACS was assessed regarding angulation, accuracy and apposition. The median follow-up was 8.46 months (interquartile range: 3.18–16.89 months). RESULTS A total of 115 consecutive patients (82 males, median age 63; interquartile range: 53–74 years) have been included. Technical success was achieved in 95.7% (110/115). Clinical success rate was 80.9% (93/115); mostly due to procedure-related death (n = 14). Overall mortality was 19.1% (22/115), with significant differences between elective/emergency procedures (log-rank: P &amp;lt; 0.001). Procedure-related serious adverse event rate was 44.3% (51/115). Procedure-related reintervention was performed in 20.9% (24/115). The cumulative incidence for reintervention differed significantly between elective/emergency cases (Gray’s test: P = 0.0033). Angulation was used in 40.9% of patients (47/115), mostly in type II arches (52.7%). Deployment accuracy was 87.8% (101/115). Sufficient apposition was present in 93.0% (107/115). CONCLUSIONS This single-centre study shows encouraging performance of the CTAG with ACS in an array of aortic pathologies. Although longer-term data must be awaited, ACS leads to overall favourable device placement. Despite ongoing advances in device technology, TEVAR remains challenging and is associated with significant burden inherent to the underlying disease.

LASER Fenestration of Thoracic Endoluminal Stent Grafts for Preservation of the Left Subclavian Artery.

LASER Fenestration of Thoracic Endoluminal Stent Grafts for Preservation of the Left Subclavian Artery.

Laser in situ Fenestration in Thoracic Endovascular Aortic Repair: A Single-Center Analysis

Laser in situ fenestration (LISF) is an expanding technique for arch vessel revascularization in thoracic endovascular aortic repair (TEVAR). We present a single center's early and midterm outcomes using adjunctive LISF with TEVAR for treatment of various arch pathologies. 24 patients underwent TEVAR with LISF (2017-2020). Patients were evaluated by an Aortic Team consisting of cardiothoracic and vascular surgeons and were deemed unfit for open surgical repair. Informed consent emphasized the procedure's off-label nature. Thoracic stent-grafts were sized by preoperative Computed Tomography Angiogram and intraoperative Intravascular Ultrasound, with oversizing determined by pathology. Extra-anatomic debranching was performed in staged or concurrent fashion based on urgency of repair and access site options for branch fenestration. A 2.3 mm Spectranetics laser was used, with access site determined at surgeon discretion. Covered balloon expandable stent-grafts were deployed with 0-10% oversizing. In 24 patients, a total of 30 fenestrations were created (LSA N=19, LCCA N=3, Innominate N=7, RSA N=1) with 1 (N=18) or 2 (N=6) fenestrations/patient. Indications included aneurysm (8), chronic dissection with aneurysmal degeneration (8), acute dissection (4), intramural hematoma (2), and pseudoaneurysm (2). 13 cases were elective, and 11 were emergent. Technical success was 100%. 12 patients underwent concurrent (N=8) or staged (N=4) extra-anatomic bypass. The major complication rate was 21%, including stroke (N=3) and 30-day mortality (N=2). The overall complication rate was 58%. Over a mean follow up of 261 days (15-864 days), 7 patients (32%) have required reinterventions. LISF for branch revascularization in TEVAR is technically feasible for treating various aortic arch pathologies, demonstrating practicality in both elective and emergent settings. With a morbidity and mortality profile that is favorable compared to that of open repair, LISF with TEVAR is a promising potential option for patients with complex arch pathology and prohibitive open surgical risk.

Midterm outcomes of fenestrated TEVAR using physician-modified endovascular grafts for zone 2.

To summarize the experience and midterm outcomes of physician-modified endovascular grafts for zone 2 thoracic endovascular aortic repair. A retrospective analysis was conducted of 51 consecutive patients (mean age 57.6 ± 12.5 years, 39 males) treated with thoracic endovascular aortic repair using physician-modified endovascular grafts for reconstructing the left subclavian artery from November 2015 to December 2019. The primary endpoints during follow-up were the overall mortality, aorta-related mortality, and major complications. The secondary endpoints were reintervention and the patency of the target branches, the demographics and technical details were also described and analyzed. Sixty-three thoracic stent-grafts were deployed in 51 patients and emergency surgery was performed in 10 patients (19.6%). Technical success was 94.1% (48/51). The incidence of perioperative complications was 15.7%, and the 30-day mortality was 0%. At a mean follow-up of 42.0 ± 14.4 months (range, 14-63 months), all the left subclavian arteries remained patent. All-cause mortality was 3.9% (2/51) and not aorta-related deaths. Estimated survival at one and three years was 98.0 ± 1.9% and 96.0 ± 2.8%, respectively. The physician-modified endovascular grafts is feasible and effective to preserve left subclavian artery in thoracic endovascular aortic repair for aortic arch pathologies with unhealthy proximal landing zone.

A technical note and report of two patients with acute aortic syndrome who were treated with the new generation Ankura thoracic stent graft

AbstractInitial experience with the new generation thoracic endograft (Ankura, Lifetech) in acute aortic syndrome was encouraging. The device was both user‐friendly and safe and it will increase the armamentory of the available endovascular treatment options.

Endovascular aortic arch repair with a pre-cannulated double-fenestrated physician-modified stent graft: a benchtop experiment.

The critical step in total endovascular aortic arch repair is to ensure alignment of fenestrations with, and thus maintenance of flow to, supra-aortic trunks. This experimental study evaluates the feasibility and accuracy of a double-fenestrated physician-modified endovascular graft [single common large fenestration for the brachiocephalic trunk and left common carotid artery and a distal small fenestration for left subclavian artery (LSA) with a preloaded guidewire for the LSA] for total endovascular aortic arch repair. Eight fresh human cadaveric thoracic aortas were harvested. Thoracic endografts with a physician-modified double fenestration were deployed for total endovascular aortic arch repair in a bench test model. A guidewire was preloaded through the distal fenestration for the LSA. All experiments were undertaken in a hybrid room under fluoroscopic guidance with subsequent angioscopy and open evaluation for assessment. Mean aortic diameter in zone 0 was 31.3 ± 3.33 mm. Mean duration for stent graft modification was 20.1 ± 5.8 min. Mean duration of the procedure was 24 ± 8.6 min. The Medtronic Valiant Captivia stent graft was used in 6 and the Cook Alpha Zenith thoracic stent graft in 2 cases. LSA catheterization was technically successful with supra-aortic trunk patency in 100% of cases. The use of a double-fenestrated stent graft with a preloaded guidewire appears to be a useful technical addition to facilitate easy and correct alignment of stent graft fenestrations with supra-aortic trunk origins.

A preliminary analysis of late structural failures of the Navion stent graft in the treatment of descending thoracic aortic aneurysms

ObjectivePatients in the Valiant Evo U.S. and international clinical trials had positive short-term outcomes; however, late structural failures, including type IIIb endoleaks have been recently discovered. Type IIIb endoleaks are serious adverse events because the repressurization of the aneurysm sac increases the risk of rupture. The purpose of the present study was to detail the imaging patterns associated with the structural failures with the aim of increasing awareness of failing graft presentation, early recognition, and prompt treatment. MethodsThe Valiant Evo clinical trial was a prospective, single-arm investigation of a thoracic stent graft system. With the recent late structural failures, sites were requested to submit all available imaging studies to date to allow the core laboratory to assess for structural failures such as type IIIb endoleaks, stent ring fractures, and stent ring enlargement. Of the 100 patients originally enrolled in the trial from 2016 to 2018, the core laboratory assessed the imaging studies performed at ≥1 year for 83 patients. ResultsNo structural failures of the graft were reported through 1 year of follow-up. At 1 to 4 years, graft structural failures were detected in 11 patients with descending thoracic aortic aneurysms. Of the 11 patients, 5 had a type IIIb endoleak. Four of the five had imaging findings showing stent fractures consistent with the location of the graft seam and one had a type IIIb endoleak attributed to calcium erosion with no stent fracture or ring enlargement. Of the four patients with stent fracture in line with the graft seam, three underwent a relining procedure that successfully excluded the type IIIb endoleak. One of these three patients died 4 days later of suspected thoracic aortic rupture because the distal thoracic endovascular aortic repair extension had been landed in a previously dissected and fragile section of the aorta. The remaining six patients had had stent ring enlargement. One of the six patients had had persistent aneurysm expansion from the time of implantation onward and had died of unknown causes. The remaining five patients have continued to be monitored. ConclusionsIn the present preliminary analysis, the imaging patterns associated with type IIIb endoleaks, stent fractures, and stent ring enlargement appear to be related to the loss of seam integrity or detachment of the stent rings from the surface of the graft material. The imaging patterns we have detailed should be closely monitored using computed tomography angiography surveillance to allow structural failures to be promptly identified and treated.

When is extra-anatomical bypass for the left subclavian artery required to prevent ischaemia after thoracic endovascular stent grafting?

Thoracic endovascular aortic repair (TEVAR) has become an accepted treatment for thoracic aortic disease. However, the principal complications relate to coverage of the thoracic aortic wall and deliberate occlusion of aortic branches over a potentially long segment. Complications include risk of stroke, spinal cord ischaemia (SCI) and arterial insufficiency to the left arm (left arm ischaemia (LAI)). This study specifically scrutinised the development of SCI and LAI after TEVAR for interventions for thoracic aortic disease from 1999 to 2020. In particular, those who underwent extra-anatomical bypass (both immediate and late) were compared to the length of thoracic aortic coverage by the stent graft. Ninety-eight patients underwent TEVAR. The presenting symptoms, pathology, procedural and follow-up data were collected prospectively with particular evidence of stroke, SCI and LAI both immediate onset and after 48 h of graft placement. Fifty underwent TEVAR for an aneurysm (thoracoabdominal aortic aneurysm), 22 for dissection, 19 for acute transection and 7 for intramural haematoma/pseudoaneurysm of the thoracic aorta. Twenty-nine (30%) required a debranching procedure to increase the proximal landing zone (1 aorto-carotid subclavian bypass, 10 carotid/carotid subclavian bypass and 18 carotid/subclavian bypass). Ten patients (10%) died within 30 days of TEVAR. Twenty-four grafts covered the left subclavian artery origin without a carotid/subclavian bypass. Five required a delayed carotid/subclavian bypass for LAI (4) and SCI (1). Six developed immediate signs of SCI after TEVAR and these 11 (group i) had a mean (SD) length of coverage of the thoracic aorta of 30.2 (10.6) cm compared to 21.5 (11.2) cm (group g) in those who had no LAI or SCI post TEVAR, p < 0.05. In this series, delayed carotid/subclavian bypass may be required for chronic arm ischaemia and less so for SCI. The length of coverage of thoracic aorta during TEVAR is a factor in the development of delayed SCI and LAI occurrence. Carotid subclavian bypass is required for certain patients undergoing TEVAR (particularly if greater than 20 cm of thoracic aorta is covered).

Chronic Erosion of a Thoracic Stent Graft Through the Left Subclavian Artery

A 66 year old patient had replacement of the supracoronary aorta for a type A aortic dissection. Three years following the index operation, she had thoracic endovascular aneurysm repair (TEVAR) of the residual type A aortic dissection at another institution. Follow up computed tomography angiography demonstrated asymptomatic erosion of the proximal sealing uncovered thoracic stent graft through the left subclavian artery (A). Left carotid-subclavian bypass, TEVAR extension with a stent graft using a Zenith TX2 device (Cook Europe, Bjaeverskov, Denmark), and occlusion of the left subclavian with a 14 mm Amplatzer vascular plug II were performed (B).Image 1

Clinical trial outcomes and thoracic aortic morphometry after one year with the Valiant Navion stent graft system

Authors' NoteOn February 17, 2021, Medtronic Incorporated issued a global voluntary recall of the Valiant Navion Thoracic Stent Graft System (the device under study in the Valiant Evo Global Clinical Program that is the subject of this publication), and instructed physicians to immediately cease use of the Valiant Navion system and return any unused product. Medtronic initiated the recall in response to three clinical trial subjects recently observed with stent fractures, two of whom have confirmed type IIIb endoleaks. The data collection, analysis, and manuscript submission occurred before the notice of this recall, and, specifically, the 100 procedures reviewed for this series were free of events at 1 year related to the reason for this device recall. The authors of this article and the manufacturer were unaware of the recently detected adverse events at the time of the preparation of the manuscript, and the 1-year trial results, and imaging-based analyses described are unchanged.Management of thoracic aortic aneurysms continues to be a challenging problem and outcomes are dependent on patient anatomy. The present publication focuses on the importance of achieving proximal and distal seals and the consideration of the temporal changes of the aortic morphology as a part of the TEVAR planning process. The authors believe there is still scientific merit in disclosing this information, despite the current nonavailability of the Valiant Navion system. ObjectiveThe Valiant Navion stent graft system (Medtronic Inc, Santa Rosa, Calif) is a third-generation device with improved conformability. We have reported the 1-year clinical trial outcomes, with a focus on an imaging-based analysis of the aortic morphology. We assessed the effects of graft implantation on the native anatomy and the effects of the 1-year changes in thoracic aorta morphology on the original seal zones of the stent graft. MethodsA total of 100 subjects were enrolled in a prospective single-arm clinical trial investigating the Valiant Navion stent graft system. An independent core laboratory (Syntactx, New York, NY) assessed the anatomic characteristics and performance outcomes. ResultsThrough 1 year of follow-up, the freedom from all-cause mortality, aneurysm-related mortality, and secondary procedures was 89.8%, 97.0%, and 94.8% respectively. Of the 100 patients, 5 had undergone a total of six secondary procedures, and 9 patients had developed an endoleak (type Ia and Ib in 1, type Ia in 1, type Ib in 3, and type II in 4 patients) within the first year. After 1 year, 2 of 76 patients (2.6%) had had an increase in their maximum aneurysm diameter of ≥5 mm, 62 (81.6%) had had stable sacs, and 12 (15.8%) had experienced sac shrinkage. Although no deployment failures had occurred, 36 of the 100 proximal (36%) and 31 of the 100 distal (31%) attachment zones were considered short according to our definitions. The stent graft had conformed to the native anatomy at implantation, because the preprocedural thoracic aorta tortuosity (1.45 ± 0.02) had not significantly changed at 1 month after implantation (1.46 ± 0.02). Despite a natural increase in thoracic tortuosity after 1 year (1.49 ± 0.02), wall apposition had been maintained over time, as evidenced by the low endoleak rates. Aortic elongation and dilation had occurred at the proximal end of the graft by an average of 1.2 mm and 1.6 mm, respectively. Aortic remodeling was more pronounced at the distal end, with an average increase of 4.2 mm in length and 2.8 mm in diameter. ConclusionsThe included patients had had positive 1-year outcomes with high freedom from mortality, endoleak development, and secondary procedures. Aortic elongation and dilation were more prevalent at the distal end, emphasizing the importance of distal attachment zone consideration as part of preoperative planning. Because aortic remodeling can be expected to continue over time, additional follow-up and imaging analysis in the trial will be necessary to assess the aortic morphology and its effects on stent graft performance.