Results of Endografting of the Aortic Arch in Different Landing Zones

Analysis of Flow Through Extra-Anatomic Bypasses Between Supra-Aortic Branches Using Particle Image Velocimetry (PIV)

Supra-aortic extra-anatomic debranch (SAD) are prosthetic surgical grafts used to revascularize head and neck arteries that would be blocked during a surgical or hybrid procedure used in treating ascending and arch of the aorta pathologies. However, bypassing the supra-aortic arteries but not occluding their orifice might introduce potential for competitive flow that reduces bypass patency. Competitive flow within the bypasses across the supra-aortic arteries has not previously been identified. This research identified haemodynamics due to prophylactic inclusion of bypasses from the brachiocephalic artery (BCA) to the left common carotid artery (LCCA), and from the LCCA to left subclavian artery (LSA). Four model configurations investigated the risk of competitive flow and the necessity of intentionally blocking the proximal LSA and/or LCCA. Particle image velocimetry (PIV) was used to assess haemodynamics in each model configuration. We found potential for competitive flow in the BCA-LCCA bypass when the LSA was blocked, in the LSA-LCCA bypass, when the LCCA alone or LCCA and LSA were blocked. Flow stagnated at the start of systole within the RCCA-LCCA bypass, along with notable recirculation zones and reciprocating flow occurring throughout systolic flow. Flow also stagnated in the LCCA-LSA bypass when the LCCA was blocked. There was a large recirculation in the LCCA-LSA bypass when both the LCCA and LSA were blocked. The presence of competitive flow in all other configurations indicated that it is necessary to block or ligate the native LCCA and LSA once the debranch is made and the thoracic endovascular aortic repair (TEVAR) completed.

A meta-analysis on the effect of proximal landing zone location on stroke and mortality in thoracic endovascular aortic repair

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) involving the aortic arch may increase the opportunity for stroke owing to disruption of cerebral circulation and embolization. In this study, a systematic meta-analysis was performed to examine the impact of proximal landing zone location on stroke and 30-day mortality after TEVAR.

METHODS

MEDLINE and Cochrane Library were searched for all original studies of TEVAR reporting outcomes of stroke or 30-day mortality for at least two adjacent proximal landing zones, based on the Ishimaru classification scheme. Forest plots were created using relative risks (RR) with 95% confidence intervals (CI). An I2 of <40% was regarded as minimal heterogeneity. A P value of <.05 was considered significant.

RESULTS

Of the 57 studies examined, a total of 22,244 patients (male 73.1%, aged 71.9 ± 11.5 years) were included in the meta-analysis, with 1693 undergoing TEVAR with proximal landing zone 0, 1931 with zone 1, 5839 with zone 2, and 3089 with zone 3 and beyond. The overall risk of clinically evident stroke was 2.7% for zones ≥3, 6.6% for zone 2, 7.7% for zone 1, and 14.2% for zone 0. More proximal landing zones were associated with higher risks of stroke compared with distal (zone 2 vs ≥3: RR, 2.14; 95% CI, 1.43-3.20; P = .0002; I2 = 56%; zone 1 vs 2: RR, 1.48; 95% CI, 1.20-1.82; P = .0002; I2 = 0%; zone 0 vs 1: RR, 1.85; 95% CI, 1.52-2.24; P < .00001; I2 = 0%). Mortality at 30 days was 2.9% for zones ≥3, 2.4% for zone 2, 3.7% for zone 1, and 9.3% for zone 0. Zone 0 was associated with higher mortality compared with zone 1 (RR, 2.30; 95% CI, 1.75-3.03; P < .00001; I2 = 0%). No significant differences were found in 30-day mortality between zones 1 and 2 (P = .13) and between zone 2 and zones ≥3 (P = .87).

CONCLUSIONS

The risk of stroke from TEVAR is lowest in zone 3 and beyond, increasing significantly as the landing zone is moved proximally. Furthermore, perioperative mortality is increased with zone 0 compared with zone 1. Therefore, risk of stent grafting in the proximal arch should be weighed against alternative surgical or nonoperative options. It is anticipated that the risk of stroke will improve with further development of stent graft technology and implantation technique.

Aortic haemodynamics and wall stress analysis following arch aneurysm repair using a single-branched endograft

Introduction

Thoracic endovascular aortic repair (TEVAR) of the arch is challenging given its complex geometry and the involvement of supra-aortic arteries. Different branched endografts have been designed for use in this region, but their haemodynamic performance and the risk for post-intervention complications are not yet clear. This study aims to examine aortic haemodynamics and biomechanical conditions following TVAR treatment of an aortic arch aneurysm with a two-component single-branched endograft.

Methods

Computational fluid dynamics and finite element analysis were applied to a patient-specific case at different stages: pre-intervention, post-intervention and follow-up. Physiologically accurate boundary conditions were used based on available clinical information.

Results

Computational results obtained from the post-intervention model confirmed technical success of the procedure in restoring normal flow to the arch. Simulations of the follow-up model, where boundary conditions were modified to reflect change in supra-aortic vessel perfusion observed on the follow-up scan, predicted normal flow patterns but high levels of wall stress (up to 1.3M MPa) and increased displacement forces in regions at risk of compromising device stability. This might have contributed to the suspected endoleaks or device migration identified at the final follow up.

Discussion

Our study demonstrated that detailed haemodynamic and biomechanical analysis can help identify possible causes for post-TEVAR complications in a patient-specific setting. Further refinement and validation of the computational workflow will allow personalised assessment to aid in surgical planning and clinical decision making.

Differences of mid-term outcomes in debranching thoracic endovascular aortic repair between zone 0 and zone 1-2 landing

OBJECTIVE

Debranching thoracic endovascular aortic repair (d-TEVAR) for zone 0 landing (Z0-TEVAR) remained challenging in aortic arch aneurysms. This study aimed to compare the mid-term outcomes between Z0-TEVAR and Z1/2-TEVAR to assess the appropriateness of Z0-TEVAR as the first-line therapy for aortic arch aneurysms in high-risk patients.

METHODS

Medical records of 200 patients who underwent d-TEVAR from 2007 to 2019 were retrospectively reviewed. Of these, 40 patients who underwent Z0-TEVAR (70% males; the median age of 82 years) and 160 Z1/2-TEVAR (78% males; the median age of 77 years) were compared. In each group, 39 patients were matched using propensity scores (PS) to adjust for differences in patient backgrounds.

RESULTS

Freedom from all-cause mortality (p < 0.001), aorta-related mortality (p < 0.001), and stroke (p = 0.001) were significantly lower in Z0-TEVAR than in Z1/2-TEVAR. Freedom from reintervention was similar between the two groups (p = 0.326). Type A dissection post-TEVAR was observed in 3 (7.5%) of Z0-TEVAR, but none in Z1/2-TEVAR (p = 0.006). Pneumonia was also more frequent in Z0-TEVAR (n = 8, 30%) than Z1/2-TEVAR (n = 4, 2.5%) (p < 0.001). PS matching also yielded worse outcomes (all-cause mortality, p = 0.017; aorta-related mortality, p = 0.046; and stroke, p = 0.027) in Z0-TEVAR than Z1/2-TEVAR.

CONCLUSIONS

Higher mid-term mortality and stroke rates after Z0-TEVAR were confirmed by PS matching. Z0-TEVAR would be an alternative for high-risk patients with arch aneurysms requiring zone 0 landing but not a reliable method.

Comprehensive review of hybrid aortic arch repair with focus on zone 0 TEVAR and our institutional experience

Even with increasing operator experience and a better understanding of the disease and the operation, intervention for aortic arch pathologies continues to struggle with relatively higher mortality, reintervention, and neurologic complications. The hybrid aortic arch repair was introduced to simplify the procedure and improve the outcome. With recent industry-driven advances, hybrid repairs are not only offered to poor surgical candidates but have become mainstream. This review discusses the evolution of hybrid repair, terminology pertinent to this technique, and results. In addition, we aim to provide a pervasive review of hybrid aortic arch repairs with reference to relevant literature for a detailed understanding. We have also discussed our institutional experience with hybrid repairs.

Stent-Graft Migration Post-Endovascular Repair of Thoracic Aorta: A Retrospective Cohort Study

Background Migration of the stent-graft post-thoracic endovascular aortic repair (TEVAR) is not uncommon; however, it is sparsely reported. The objective of this study was to assess the incidence, risk factors, and complications of stent-graft migration post-TEVAR.

Materials and Methods Thirty-one patients who underwent TEVAR were retrospectively analyzed. The demographic, anatomical, and procedure-related factors were assessed. The measurements were done along the greater curvature of aorta around two fixed anatomic landmarks, that is, left common carotid artery or neoinnominate artery (hybrid repair) proximally and celiac artery distally. Aortic elongation and migration at proximal, distal, as well as at overlapping zone were measured. More than 10 mm of migration was considered significant.

Results Significant migration was observed in six (19%) patients. No significant migration was observed in the overlapping zone. The proximal landing zone 3 (odds ratio [OR] 12.78, p 0.01) was a significant risk factor, whereas landing zone 2 was a protective factor against the migration (OR 0.08, p 0.02). The odds for migration were more in segments I/3 and II/3 compared with I/2 and II/2, respectively, as per Modified Arch Landing Areas Nomenclature. A single complication was seen in the migration group which was treated by an overlapping stent graft.

Conclusion The stent-graft migration after TEVAR is not uncommon. Type 3 proximal landing zone was a significant risk factor for migration with an increased risk toward I/3 and II/3. Proximal landing zone 2 as well as adequate overlapping distance in multiple stent grafts can prevent migration.

Ethical Approval No IECPG-227/24.06.2020

Early and Midterm Outcomes of Type II Hybrid Arch Repair for Complex Aortic Arch Pathology

Background

The hybrid arch repair (HAR) is an appealing surgical option in the management of aortic arch diseases. The aim is to evaluate the short and mid-term outcomes of type II HAR involving replacement of the ascending aorta, arch debranching, and zone 0 stent graft deployment in diverse arch pathologies.

Methods

200 patients with various diffuse aortic pathologies involving the arch were enrolled between 2016 and 2019. Complex arch diseases included acute type A dissection (n = 129, 64.5%), acute type B dissection (n = 16, 8.0%), aortic arch aneurysm (n = 42, 21.0%) and penetrating arch ulcer (n = 13, 6.5%). Mortality, morbidity, survival and re-intervention were analyzed.

Results

The overall 30-day mortality rate was 8.0% (16/200). Stroke was present in 3.5% (7/200) of the general cohort and spinal cord injury was occurred in 3.0% (6/200). Multivariable logistic analysis showed that cardiac malperfusion and CPB time were the risk factors associated with 30-day mortality. The mean follow-up duration was 25.9 months (range 1–57.2 months), and the 3-year survival rate was 83.1%. On Cox regression analysis, age, diabetes, cardiac malperfusion and CPB time predicted short and mid-term overall mortality. A total of 3 patients required reintervention during the follow-up due to the thrombosis of epiaortic artificial vessels (n = 1), anastomotic leak at the site of the proximal ascending aorta (n = 1) and the type I endoleak (n = 1).

Conclusions

Type II HAR was performed with satisfactory early and mid-term outcomes in complex aortic arch pathologies.

Mid-term outcomes of hybrid debranching endovascular aortic arch repair in landing zones 0-2

OBJECTIVES

The aim of this study is to summarize a single-center experience of hybrid debranching endovascular repair of the aortic arch and proximal descending thoracic aorta (DTA) with regard to the mid-term outcomes with highlighting the difference between the landing zones 0-2.

METHODS

A retrospective review of data from a prospectively collected registry (Gangnam Severance Endovascular Aortic Registry) was performed. From among 332 patients whose aortic pathology was managed with TEVAR, 112 patients who underwent hybrid arch repair during the study period between 2012 and 2016 were identified. The patients were grouped into three cohorts according to the proximal landing zones (0, 1, and 2) of Ishimaru. The early outcome (30-days) in terms of mortality, morbidity, supra-aortic vessels patency, and presence of endoleak were analyzed. The survival, freedom from re-intervention, and major complications during follow-up were demonstrated.

RESULTS

During the study period. 112 patients (mean age 65±7, 79% males) were included. The patients were distributed in three cohorts: 8 (7%) patients with proximal landing zone 0, 20 (18%) with zone 1, and 80 (75%) with zone 2 hybrid aortic arch repair. Technical success was achieved in 7 (88%), 19 (90%), and 79 (94%) patients for zones 0, 1, and 2, respectively. The mean intensive care unit (ICU) stay was shorter in zone 2 (p = .005). The mean total hospital stay was shorter in zone 2 (p = .03). The overall in-hospital mortality rate was 5% (4/112). There was no spinal cord ischemia or early surgical conversion. Renal function deterioration was seen more but not significantly in zone 0 patients (p = .08). Respiratory failure was seen significantly in zone 0 patients (p = .01). Stroke occurred in 6/44 (14%) patients with degenerative aneurysm versus 1/60 (2%) patients with aortic dissection (p =.06). Early CTA showed 100% patency of the supra-aortic vessels. The early endoleak rate was significant in zone 0 patients (p = .008). The mean follow-up period was (32±19 months). The survival rates and freedom from re-intervention were not statistically significant among the three zones. However, the survival rate and freedom from intervention tend to be higher in zone 2 versus zone 0 (p = .07 and .09), respectively.

CONCLUSION

Hybrid debranching endovascular aortic arch repair is feasible and relatively safe with acceptable mid-term outcomes. Zone 0 patients has worse early and late outcomes in comparison to other zones. Careful patient selection and improved endovascular technology may be the key to improve the outcomes.

Morphology of the left subclavian artery: implications for single-branched endovascular aortic arch repair

OBJECTIVES

Our goal was to evaluate the morphology of the aortic arch, focusing on the left subclavian artery (LSA), and to anticipate implications for single-branched endovascular aortic arch repair.

METHODS

We performed a morphological analysis of computed tomography angiography scans of 322 patients between January 2002 and December 2018. Arch type and distance between arch vessels on the convexity were evaluated. We defined 3 morphological types: U-type distance between the left common carotid artery (LCCA) and LSA offspring >10 mm; V-type distance between the LCCA and LSA offspring <10 mm and W-type isolated left vertebral artery offspring from the aortic arch.

RESULTS

Most patients presented a type III arch [50% (n = 161)]. The median distance from the brachiocephalic trunk offspring to the LCCA offspring measured 2.5 mm (2.0-3.0 mm) and that between the LCCA offspring and the LSA offspring was 6.5 mm (4.0-11.0 mm). We observed no significant difference based on the morphological type (V versus U versus W) in the brachiocephalic trunk-LCCA distance, but there were significant differences in the LCCA-LSA distance between types V and U (P < 0.001) and between types V and W (P < 0.001). Interestingly, we found no significant difference in the LCCA-LSA distance between types U and W. We noted a significant difference in the median diameter of the LSA according to U, V and W types: V type versus U type, 12.5 vs 13.5 mm (P = 0.033) as well as U type versus W type, 13.5 vs 10.5 mm (P < 0.001) and V type versus W type, 12.5 vs 10.5 mm (P < 0.002). The distances between the LSA offspring and left vertebral artery offspring between types U and V did not differ significantly.

CONCLUSIONS

Our categorization of the U, V and W types of the LSA can help us anticipate shapes and distances and thereby function as an initial evaluation tool for predicting single branched endovascular aortic arch repair involving the LSA.

[Hybrid repair of aortic arch aneurysm]

BACKGROUND

The management of aortic arch aneurysms is challenging. If conventional surgery cannot be performed in high risk patients, endovascular treatment is confronted to the problem of endoleaks at long term. However, the hybrid repair combining a first surgical step and a second endovascular step is a new technique recently introduced in the therapeutic alternatives of aortic arch aneurysm but its long-term results are not well known.

METHODS

We report a series of four patients who received hybrid treatment for aortic arch aneurysms in our department between 2016 and 2018.

RESULTS

These were 3 men and 1 woman with an average age of 63 years [55-80 years]. All were hypertensive and only one patient had diabetes. The aneurysm was symptomatic of chest pain in all cases and it was ruptured in only one case. Preoperatively, the hemodynamic state was stable in the four patients with a mean aneurysm diameter of 60 mm [48-79 mm] on CT angiography and the landing zone was zone 0 in all cases. Under general anesthesia, the 1st step was surgical with the performance of an aorto-bicarotid bypass associated with a re-implantation of the left subclavian artery and a disconnection of the supraortic trunks. The 2nd stage was endovascular by the femoral route; with release of an aortic stent graft covering the ostia of all supraortic trunks. The final angiographic check-up showed complete exclusion of the aneurysm in all cases. The immediate postoperative follow-up was straightforward except for the onset of septic shock and death in a patient with an aneurysm ruptured in the left pulmonary branch initially. The mean follow-up was 12 months with a CT scan control which confirms the complete exclusion of the aneurysm and the absence of endoleak.

Determination of Optimal and Safest Proximal Sealing Length During Thoracic Endovascular Aortic Repair

OBJECTIVE

To determine the optimal and safest proximal sealing length (PSL) during thoracic endovascular aortic repair (TEVAR), depending on anatomical aortic arch types and proximal landing zones (LZs).

METHODS

This was a single centre retrospective observational study of consecutive TEVAR patients (2008-2020). All aortic pathologies requiring Ishimaru landing zone (LZ) 0 - 3 were included; results were stratified by aortic arch type. The PSL was measured as the length of complete aortic wall to endograft apposition at the level of the proximal neck. The primary endpoint was proximal failure (type 1A endoleak, endograft migration, or re-intervention requiring proximal graft extension). Freedom from proximal failure was estimated with Kaplan-Meier curves. An "optimal" sealing length (PSL cutoff maximising sensitivity + specificity for proximal failure) and "safest length" (PSL cutoff determining ≥ 90% sensitivity) were identified using receiver operating characteristic curve analysis.

RESULTS

One hundred and forty patients received TEVAR; mean ± standard deviation PSL was 29 ± 9 mm. Freedom from proximal endograft failure at five years (median 31 months) was 82.4% (95% confidence interval [CI] 72 - 95); the shorter the PSL, the greater was the risk of failure (hazard ratio 0.90, 95% CI 0.84 - 0.97; p = .004). Overall optimal and safest PSL were 25 mm (sensitivity 78%, specificity 66%) and 30 mm (sensitivity 92%, specificity 30%), respectively. In type I arch, the optimal PSL was 22 mm (sensitivity 50%, specificity 87%). In type II, the optimal PSL was 25 mm (sensitivity 89%, specificity 59%) overall and 27 mm for type II/LZ 2 - 3 (sensitivity 31%, specificity 68%). For type III, the optimal PSL was 27 mm (sensitivity 80%, specificity 87%); the safest was 30 mm (sensitivity 100%, specificity 61%) In type III/LZ 2 - 3, the optimal PSL was 27 mm (sensitivity 31%, specificity 68%) and safest was 30 mm (sensitivity 100%, specificity 55%).

CONCLUSION

A 20 mm PSL may be acceptable only for type I arches. For types II/III, that represent the majority of cases, a 25 - 30 mm PSL may be required for a safe and durable TEVAR.

Drag Forces after Thoracic Endovascular Aortic Repair. General Review of the Literature

BACKGROUND

Despite the great evolution of endograft devices for thoracic endovascular aortic repair (TEVAR), threatening related complication such as graft migration and endoleaks still occur during follow up. The Drag Forces (DF), that is the displacement forces that play a role in graft migration and endoleaks caused by the blood flow against the thoracic graft, can be studied by means of Computational Fluid Dynamics (CFD).

METHOD

A general review of papers found in current literature was performed. CFD studies available on the topic of thoracic aortic diseases and DF were analyzed. All anatomic, hemodynamics or graft related factors which could have an impact on DF were reported.

RESULTS

Different factors deeply influence DF magnitude in the different site of the Ishimaru's zones classification: angulation, tortuosity and length of the landing zone, graft diameter, length and deployment position, blood pressure, pulse waveform, blood viscosity and patient heart rate have been related to the magnitude of DF. Moreover, also the three-dimensional orientation of DF is emerging as a fundamental issue from CFD studies. DF can be divided in sideways and upward components. The former, even of higher magnitude in zone 0, maintain always an orthogonal orientation and does not change in any type of aortic arch; the latter result strictly related to the anatomic complexity of the aortic arch with values up to four times higher in zone 3.

CONCLUSION

Different DF magnitude and orientation could explain how TEVAR have higher rate of migration and endoleaks when we face with more complex aortic anatomies. All these aspects should be foreseen during the planning of TEVAR procedure. In this field, collaboration between physicians and engineers is crucial, as both parts have a primary role in understanding and describing hidden aspects involved in TEVAR procedures.

Zone 1 Aortic Arch Hybrid Endovascular Repair with Extra-anatomical Bypass: A Meta-analysis

BACKGROUND

The aim of this meta-analysis is to determine the morbidity and mortality outcomes of adult patients with aortic arch disease managed with extra-anatomical bypass avoiding median sternotomy and cardiopulmonary bypass, with simultaneous or staged hybrid zone 1 endovascular aortic repair.

METHODS

Systematic literature searches of the MEDLINE, EMBASE, and Cochrane databases were carried out to identify relevant studies on zone 1 hybrid arch repair. Extracted data were analyzed by random effects models. Primary outcomes included 30-day or in-hospital mortality. Longitudinal survival was analyzed up to 7 years from date of operation. Secondary outcomes included in-hospital morbidity, as well as late endoleak and reintervention.

RESULTS

Twenty studies incorporating 348 patients were included. In-hospital or 30-day mortality was 10.1% (95% confidence interval, 6.7-14.9%). Overall operative technical success was 89.8% (83.7-93.8%). Early type 1 endoleak rate was 14.0% (7.4-24.7%). Stroke prevalence was 9.5% (6.1-14.3%). Spinal cord paraplegia prevalence was 3.8% (1.9-7.6%). Retrograde aortic dissection prevalence was 4.1% (1.5-10.6%). Survival at 1 year postoperatively was 77.2% (66.1-85.4%). Survival at 3 years postoperatively was 73.7% (59.2-84.4%). Survival beyond 4 years postoperatively (range 58-80 months) was 65.9% (53.6-76.4%). Late type 1 endoleak prevalence was 11.8% (5.5-23.7%). Overall rate of reintervention was 11.6% (6.4-20.1%).

CONCLUSIONS

Zone 1 hybrid repair has evidence for satisfactory short- and long-term morbidity/mortality outcomes and may be considered as an alternative approach to aortic arch disease.

Determining the Optimal Proximal Landing Zone for TEVAR in the Aortic Arch: Comparing the Occurrence of the Bird-Beak Phenomenon in Zone 0 vs Zones 1 and 2

Purpose: To identify the optimal proximal landing zone for thoracic aortic endovascular repair (TEVAR) of aortic arch pathologies so as to avoid the bird-beak phenomenon that leads to type Ia endoleak. Materials and Methods: A retrospective single-center review was conducted of 164 patients (mean age 70.3±10.8 years, range 29–93; 127 men) who underwent repairs of the aortic arch using hybrid TEVAR from April 2008 to March 2017. The patients were divided into 2 groups according to the proximal landing zone: 43 zone 0 patients (26.2%) had total debranching TEVAR (n=18) or total endovascular aortic repair (n=25) while 121 patients (73.8%) had TEVAR landing in zones 1 (n=41) or 2 (n=80). Bird-beak configurations, endoleaks, and stent migrations were assessed on the postoperative and latest computed tomography angiography (CTA) scans. Overall survival and freedom from the bird-beak configuration, aorta-related death, and aortic events were estimated using the Kaplan-Meier method. Hazard ratios (HR) were calculated with the 95% confidence interval (CI). Results: All procedures were successful, without any 30-day mortality. There were 3 early complications (1.8%; all strokes) and 10 early endoleaks (6.1%; no type Ia). On the first postoperative CTA, 42 patients (25.6%) had a bird-beak configuration. The zone 0 patients had significantly fewer (p<0.001), shorter (p<0.004), and less angulated (p<0.001) bird-beak configurations than in zones 1–2. The mean follow-up period was 4.2 years (range 0.5–8.8). There were 18 late deaths (11.0%); only one was related to the aorta (rupture due to a type Ib endoleak in a zone 0 patient). The 5-year freedom from aorta-related death was not significantly different between groups (zone 0: 96.9% vs zones 1–2: 100%, p=0.080). On the latest CTA, 51 (31.0%) patients had a bird-beak configuration; of those, 22 (13.4%) showed >3-mm progression. The freedom from bird-beak configuration estimate was significantly higher in the zone 0 group (95.4%) vs zones 1–2 (57.8%; HR 0.10, 95% CI 0.02 to 0.31, p<0.001). There were 9 late endoleaks (4 type Ia; none in the zone 0 group). The rate of stent-graft migration was significantly lower in the zone 0 group (2.3% vs 14.1% in zones 1–2, p=0.035). Conclusion: Early and most late results in zone 0 TEVAR were equal to those in zones 1 and 2; however, there were no late type Ia endoleaks and fewer bird-beak configurations associated with zone 0 TEVAR, which suggests that zone 0 landing is advantageous for preventing these complications.

Is debranching thoracic endovascular aortic repair acceptable as the first choice for arch aneurysm in the elderly?

OBJECTIVES

This study aimed to assess differences in midterm outcomes between total arch replacement (TAR) and debranching thoracic endovascular aortic repair (d-TEVAR) and to evaluate the validity of d-TEVAR as the preferred treatment choice for aortic arch aneurysm in the elderly.

METHODS

We reviewed the case histories of 86 patients who had undergone TAR (64 men; mean age 78 ± 2.9 years) and 121 patients who had undergone d-TEVAR (90 men; mean age 82 ± 4.5 years) between 2007 and 2017; of these patients, 50 from each group were matched based on propensity scores to adjust for differences in patient characteristics.

RESULTS

Rates of freedom from all-cause mortality at 2 and 4 years were similar between the 2 groups (88% and 77% in the TAR group vs 82% and 64% in the d-TEVAR group, P = 0.11), but rates of freedom from reintervention at 2 and 4 years were significantly higher in the TAR group (100% and 96%) than in the d-TEVAR group (97% and 88%) (P = 0.004). Propensity score matching yielded similar survival rates of 88% and 85% for TAR vs 86% and 71% for d-TEVAR (P = 0.53) and comparable freedom from reintervention rates (100% and 97% in TAR, 98% and 90% in d-TEVAR, P = 0.16) at 2 and 4 years. Cox regression analysis identified previous cerebral infarction [hazard ratio (HR) 3.9; P = 0.005 in TAR/HR 3.1; P = 0.002 in d-TEVAR] as an independent positive predictor of overall mortality in both groups.

CONCLUSIONS

Midterm outcomes after TAR and d-TEVAR were satisfactory and propensity score matching-based evaluation revealed no significant differences in outcomes, implying that d-TEVAR is an acceptable first-choice procedure for aortic arch aneurysm in patients older than 75 years.

Late complications after hybrid aortic arch repair

OBJECTIVE

Although hybrid arch repair has gained widespread application as an alternative option for high-risk patients, concerns about its long-term durability remain an important issue. The aim of this study was to investigate late complications after hybrid arch repair.

METHODS

From January 2002 to December 2017, hybrid arch repair was performed in 65 patients with aortic arch disease (median age, 66.1 years; range, 41-86 years). Hybrid arch repair was defined as debranching involving at least one supra-aortic vessel bypass and simultaneous or staged endovascular thoracic stent grafting. We retrospectively analyzed late complications including reintervention, open conversion, and aortic-related death. The median follow-up period was 60.1 months (range, 1-170 months).

RESULTS

The in-hospital mortality rate was 6% (4/65). Except for early death (n = 4) and early open conversion (n = 2), late complications were observed in 25 patients (25/59 [42%]). The median time interval between the initial procedure and late complication was 36.6 months (range, 1-92 months). Late complications included delayed type I endoleak (n = 8), distal stent-induced new entry (n = 3), stent migration (n = 3), retrograde type A dissection (n = 2), aortopulmonary fistula (n = 2), aortoesophageal fistula (n = 1), stent fracture (n = 1), infection (n = 1), and sudden death (n = 4). Six of these patients (10%) underwent late open conversion. The overall survival rates at 3 years and 6 years were 71.1 ± 7.4% and 57.2 ± 11.3%, respectively. The aortic event-free rates at 3 years and 6 years were 52.1 ± 7.3% and 39.4 ± 10.3%, respectively.

CONCLUSIONS

Late complications in hybrid arch repair occurred in a substantial proportion of patients during midterm follow-up. Regardless of zone type, the incidence of late complications was relatively high. This study suggests that timely reintervention and open conversion are important for rescuing patients, but repeated reinterventions and conservative strategies are not recommended. Aggressive management and life-long surveillance after hybrid arch repair are mandatory for better outcomes.

Hybrid Repair of a Saccular Aortic Arch Aneurysm Ruptured in the Left Pulmonary Bronchus

The rupture of aortic arch aneurysm is rare but serious and a life-threatening pathologic condition. We report a case of an 80-year-old woman who was admitted to our department for a rupture of a saccular aortic arch aneurysm in the left pulmonary bronchus. There was no landing zone in the aortic arch. First, we performed a total supra-aortic debranching and a bifurcated graft bypass from the ascending aorta to both the innominate artery and the left carotid artery. Then, we implanted in the aortic arch an endoprosthesis covering the origin of all supra-aortic trunks. Final angiography was satisfactory. The patient died 8 days later due to pulmonary-originated septic shock. Aortic arch hybrid procedures show a variety of severe complications associated with a relevant morbidity, mortality, and reintervention rate. Prognosis of rupture depends not only on the hemorrhage caused but also on the potential infection.

Neurologic Outcomes in Aortic Arch Repair With Frozen Elephant Trunk Versus 2-Stage Hybrid Repair

BACKGROUND

We compared outcomes of single-stage hybrid aortic arch replacement (frozen elephant trunk) versus 2-stage hybrid repairs with primary open arch procedures followed by thoracic endovascular stenting.

METHODS

This study reports a single-center retrospective review (2003 to 2016) of 118 patients undergoing hybrid repair of the aortic arch including 48 single-stage repairs versus 70 two-stage repairs.

RESULTS

Single-stage repair was performed in 48 patients, including 31 (64.6%) men and 17 (35.4%) women with a mean age of 64 ± 11 years and a 2-stage procedure was performed in 70 patients, including 42 (60%) men and 28 (40%) women with a mean age of 65.67 ± 13.3 years (p = 0.46). More emergent single-stage procedures were performed in 23 of 48 (47.9%) patients versus 2-stage procedures in 8 of 70 (11.43%) patients (p < 0.001). Between the single- and 2-stage groups, there was no difference in stroke (6.25% [3 of 48] versus 14.28% [10 of 70]; p = 0.23), spinal cord ischemia (4.16% [2 of 48] versus 5.7% [4 of 70]; p = 1.0), or 30-day mortality rate: 8 of 48 (16.7%) patients versus a combined 30-day mortality rate of the 2-stage procedure of 14.8% (4 of 70 [5.7%] at the first stage and 5 of 55 [9.1%] at the second stage; p = 0.56), respectively. After exclusion of the 30-day mortality, midterm survival was 86% at 1 to 2 years for single-stage patients versus 80% at 1 year and 46% at 2 years for the 2-stage patients (p = 0.0019).

CONCLUSIONS

Both single-stage and 2-stage hybrid arch replacements are effective approaches for treating complex aortic arch diseases. Early deaths and neurological outcomes in the single-stage group are comparable to those in the combined 2-stage group. Furthermore, in this series, patients who had a single-stage hybrid procedure had a higher survival rate at 2 years.

Treatment of aortic arch aneurysms: Open surgery or hybrid procedure?

Background

This study aims to compare the results of hybrid procedure and open surgery for the treatment of aortic arch aneurysms.

Methods

Twenty-six p atients (21 m ales, 5 females; m ean a ge 56.6±12.4 years; range, 20 to 83 years) who underwent total aortic arch replacement for aortic arch aneurysm between January 2004 and January 2010 were retrospectively analyzed. The patients were divided into two groups: open conventional surgery group (group 1, n=15) and hybrid procedure (total debranching of the aortic arch and simultaneous endovascular stent) group (group 2, n=11). Survival rates and need for reoperation were compared between the groups.

Results

The hybrid procedure was found to be more favorable in terms of postoperative revision, extubation period, and drainage amounts. However, there was no statistically significant difference in the survival rates, need for reoperation, and major adverse cardiovascular events between the groups.

Conclusion

Our study results suggest that conventional open surgery and hybrid procedure are similar in terms of survival and short-to-mid-term results in patients undergoing total aortic arch replacement for aortic arch aneurysm.

Hybrid Treatment with Complete Transposition of Supra-Aortic Trunks versus Conventional Surgery for the Treatment of Aortic Arch Aneurysm

OBJECTIVE

The disease of the aortic arch is traditionally approached by open surgical repair requiring cardiopulmonary bypass and circulatory arrest. This study performed a retrospective analysis comparing outcomes through primary hybrid patients submitted to aortic arch surgery without cardiopulmonary bypass with patients submitted to conventional open surgery.

METHODS

25 patients submitted to the aortic arch surgery were selected in the period 2003-2012 at the Madre Teresa Hospital in the city of Belo Horizonte, Brazil; 13 of these underwent hybrid technique without cardiopulmonary bypass and 12 underwent conventional open surgery.

RESULTS

The mortality rate for the hybrid group was 23% and for the conventional surgery group was 17% (P=0.248). The postoperative complication rate was also similar in both groups, with no significant difference.

CONCLUSION

Both techniques proved to be similar in mortality and morbidity. However, due to the small sample, more analytical studies with larger samples and long-term follow-up are needed to clarify this issue.

Endovascular Stent Graft Repair of Localized Acute Aortic Intramural Hematoma: A Case Report and Literature Review

Aortic intramural hematoma (IMH) is a variant of acute aortic syndrome, which can be life-threatening. Ascending aorta IMHs, particularly accompanied by penetrating aortic ulcer (PAU), can cause dissection, rupture, and cardiac tamponade. Therefore, early surgical treatment is recommended for IMHs of the ascending aorta. Herein, we present the case of a 60-year-old male patient who was on warfarin sodium treatment and in whom an IMH localized to the arcus aorta was detected incidentally via computed tomography, with the suspicion of pulmonary embolism, and an endovascular stent graft was inserted into the arcus aorta. This case highlights the importance of following ulcerated aortic plaques and suggests that IMH can be successfully treated with endovascular stent grafting.

Hybrid Repair of Aortic Arch Aneurysms with Endografting of the Ascending Aorta

BACKGROUND

Different "hybrid" techniques that combine open debranching of the supra-aortic vessels with endografting of the aortic arch have emerged as alternatives to the open arch repair in high-risk patients. This study aims to review the early and mid-term results of single-stage hybrid arch repair with ascending aorta stent graft deployment for aortic arch aneurysms and dissections.

METHODS

Between June 2006 and May 2015, five consecutive patients, with an age range of 54-78 years, with complex aortic arch diseases, were treated with a hybrid approach in which the endograft had a proximal landing zone in the ascending aorta. Indications included: acute and chronic type A aortic dissections and three arch aneurysms associated with distal aortic pathology. Length of postoperative clinical and imaging follow-up ranged from 10 to 121 months and was completed in all patients.

RESULTS

Technical success of the endografting was achieved in all cases. There was one in-hospital mortality secondary to pulmonary embolism, one case of retrograde type A aortic dissection (RTAD) detected before discharge and one case of late type Ib endoleak that required an endografting procedure. No postoperative stroke or transient or permanent spinal cord ischemia occurred.

CONCLUSION

Hybrid arch repair with endograft landing in zone 0 may decrease mortality and morbidity in high-risk patients. doi: 10.1111/jocs.12735 (J Card Surg 2016;31:341-347).

Apparatus for Comparison of Pullout Forces for Various Thoracic Stent Grafts at Varying Neck Angulations and Oversizes

BACKGROUND

The purpose of this study is to provide an apparatus for comparison of pullout forces for various thoracic stent grafts at varying neck angulations and oversizes.

METHODS

An in vitro platform capable of performing pullout tests was used on stent grafts in angulated silicone tubes designed for this study (0°, 45°, 90°, and 135° with a 32-mm inner diameter) in a temperature-controlled chamber (37 ± 2°C). Three commercial stent grafts with sizes commonly used in Taiwan (Valiant: 34, 36, 38, and 40 mm; Zenith TX2: 34, 36, 38, and 40 mm; and TAG: 34, 37, and 40 mm) were used, and each size was tested 8 times for each angulation condition.

RESULTS

The mean dislodgement forces (DFs) at 0° angulation within 10-20% oversize were approximately 22.7, 9.6, and 9.0 N for the Valiant, Zenith TX2, and TAG devices, respectively, whereas the mean DFs decreased by 46%, 38%, and 50% to 12.3, 5.9, and 4.5 N when the angulation reached 135°. Regression analysis shows that neck angulation was a significant factor for the Valiant and Zenith TX2 devices (P < 0.0001 and P < 0.0001, respectively) but not for the TAG device (P = 0.483). In addition, oversize and interactions between variables (angulation × oversize) exhibited significant effects on the DFs for all devices (P < 0.0001).

CONCLUSIONS

We successfully built up an apparatus for comparison of pullout forces for various thoracic stent grafts at varying neck angulations and oversizes. With the empirical comparative data of different brand stent grafts under various conditions shown and compared, our findings suggest that aortic neck angulation has a negative correlation with stent-graft fixation. To have better stent-graft fixation and seal in the aortic arch for thoracic endovascular aortic repair, a longer landing zone with cautiously selected oversize is a more suitable selection.

Utility of Chimney Stentgraft Technique for Patients with Short Zone 1

PURPOSE

Arch aneurysm combined with insufficient Zone 1 length remains challenging. While a chimney stentgraft with supra-aortic bypass is a recognized solution for arch aneurysm, no definite strategy has been established yet. The aim of this study was to investigate efficacy of chimney stentgraft for patients with zone 1 of insufficient length.

METHODS

Between 2011 and 2013, 10 consecutive patients with aortic arch aneurysm who were treated with a chimney stentgraft were retrospectively reviewed. The minimum length of zone 1 and length of landing zone inside zone 0 were measured on pre-/post-operative 3D-CT.

RESULTS

Neither in-hospital mortality nor postoperative stroke was encountered. The minimum median length of zone 1 (zone 2 for bovine aortic arch of two patients) on preoperative 3D-CT was 10.1 mm [range: 3.9-15.3]. On postoperative 3D-CT, the median proximal landing length on a major curvature proximal to brachio-cephalic artery was 37.5 [range: 20.9-63.9] mm. Type Ia endoleak was observed in two patients with a landing length along the major curvature of less than 30 mm.

CONCLUSION

For patients with insufficient length of zone 1, aneurysm exclusion could be achieved with a chimney stentgraft ensuring sufficient length (>30 mm) of the landing zone inside the ascending aorta along major curvature.

Aortic Arch Morphology and Aortic Length in Patients with Dissection, Traumatic, and Aneurysmal Disease

OBJECTIVES

To assess aortic arch morphology and aortic length in patients with dissection, traumatic injury, and aneurysm undergoing TEVAR, and to identify characteristics specific to different pathologies.

METHOD

This was a retrospective analysis of the aortic arch morphology and aortic length of dissection, traumatic injury, and aneurysmal patients. Computed tomography imaging was evaluated of 210 patients (49 dissection, 99 traumatic injury, 62 aneurysm) enrolled in three trials that received the conformable GORE TAG thoracic endoprosthesis. The mean age of trauma patients was 43 ± 19.6 years, 57 ± 11.7 years for dissection and 72 ± 9.6 years for aneurysm patients. A standardized protocol was used to measure aortic arch diameter, length, and take-off angle and clockface orientation of branch vessels. Differences in arch anatomy and length were assessed using ANOVA and independent t tests.

RESULTS

Of the 210 arches evaluated, 22% had arch vessel common trunk configurations. The aortic diameter and the distance from the left main coronary (LMC) to the left common carotid (LCC) were greater in dissection patients than in trauma or aneurysm patients (p < .001). Aortic diameter in aneurysm patients was greater compared with trauma patients (p < .05). The distances from the branch vessels to the celiac artery (CA) were greater in dissection and aneurysm patients than in trauma patients (p < .001). The take-off angle of the innominate (I), LCCA, and left subclavian (LS) were greater, between 19% and 36%, in trauma patients than in dissection and aneurysm patients (p < .001). Clockface orientation of the arch vessels varies between pathologies.

CONCLUSIONS

Arch anatomy has significant morphologic differences when comparing aortic pathologies. Describing these differences in a large sample of patients is beneficial for device designs and patient selection.

Results of type II hybrid arch repair with zone 0 stent graft deployment for complex aortic arch pathology

OBJECTIVE

To review the early results of a less invasive, single-stage hybrid arch procedure involving replacement of the ascending aorta, arch debranching, and zone 0 antegrade stent graft deployment.

METHODS

Between May 2007 and January 2012, 20 patients with both acute and chronic aortic pathology were managed at 2 institutions with a type 2 hybrid arch procedure. Indications included diffuse atherosclerotic aneurysm, false lumen expansion of chronic aortic dissections, penetrating atherosclerotic ulcer, and acute type A dissection. Mean age was 67 ± 16.8 years with a mean European System for Cardiac Operative Risk Evaluation II score of 29.5 ± 19.4. Postoperative clinical and imaging follow-up was complete to a mean 18.5 ± 15.3 months.

RESULTS

Successful zone 0 stent graft deployment was achieved in all cases. There was 1 in-hospital mortality (5%). A second death occurred at 40 days postoperation. Other complications included a permanent neurologic deficit in 1 patient (5%), transient paraplegia in 4 patients (20%), and 3 patients had respiratory complications (15%). There were no cases of renal failure requiring dialysis. Stent-related complications were identified in 4 patients (20%), including 3 type I endoleaks, none of which were at zone 0. There was 1 type II endoleak and a case of stent infolding. Two patients required a second successful endografting procedure.

CONCLUSIONS

This single-stage hybrid arch procedure offers an alternative approach to complex diffuse aortic pathology involving the arch. Replacement of the ascending aorta provides a safe location for zone 0 stent graft deployment, eliminating complications of proximal deployment in a native diseased aorta.

Hybrid repair of aortic arch pathology

The objective was to evaluate a 13-year single-centre experience of arch endovascular aortic repair using the hybrid approach. Between 1999 and 2013, 491 patients were treated with endografts for thoracic aortic pathologies. The aortic arch was involved in 179 (36.5%) patients (128 men; mean age 70.2 ± 10.8 years, range 27-84). A hybrid approach was performed for all Zone 0 and 1 procedures and in nearly half of Zone 2 procedures. Early and mid-term outcomes were reviewed retrospectively. Overall primary technical success (24 h) was achieved in 162 (90.5%) of the 179 cases; 2 deaths and 15 Type 1 endoleaks were observed. Clinical success at 30 days was achieved in 161 (89.9%) of the 179 patients, with a mortality rate of 4.5% (8/179). Short-term clinical success at 6 months was achieved in 169 (94.4%) of the 179 patients; the rates for the different landing zones did not differ significantly. At a mean follow-up of 27.3 ± 15.7 months (range 1-94), the mid-term clinical success was 165 (92.2%) of the 179 patients; the rates among the different proximal zones did not differ significantly. In selected patients, early and mid-term outcomes of arch endovascular aortic repair using the hybrid approach are promising; however, mortality and morbidity are not negligible. Our results may have practical implications for the ongoing evaluation of the hybrid procedure in the aortic arch, as well as for patients fit for traditional surgery.

Clinical outcomes in hybrid repair procedures for pathologies involving the aortic arch

Objective

Fifty patients with complex aortic disease, who received hybrid treatment of the aortic arch with supra-aortic debranching and endovascular stent-graft repair, were evaluated in regard to events of primary (survival and technical success) and secondary (procedure-related complications) interest.

Methods

The single-center study was conducted over an eight-year period from December 2004 to December 2012. Treated medical conditions included 23 aortic aneurysms (46%), 21 aortic dissections (42%), and six penetrating aortic ulcers (12%). Procedures were divided into groups of elective, urgent, and emergent.

Results

Twenty-eight (56%) patients were operated electively, 15 (30%) urgently, and seven (14%) emergently. Sternotomy, cardiopulmonary bypass, and deep hypothermic circulatory arrest were required in 12 (24%) patients. The primary technical success rate was 86% and raised to 92% ( n = 46) of secondary technical success rate after therapy of three type I endoleaks. The 30-day mortality added up to 16.0%, and the mean time of survival was 49.3 months. In a total of eight (16%) patients, an endoleak occurred (five endoleaks type I, three endoleaks type II), while nine (18%) of patients suffered a perioperative stroke.

Conclusions

In severely ill patients with complex aortic diseases, hybrid therapy may offer a promising alternative to conventional open repair.

Anatomical characteristics of the thoracic aortic arch in an Asian population

Background: Endovascular repair of the aortic arch is often unsatisfactory due to poor stent-vessel conformity and inadequate landing zones.

Objective: To study the anatomical characteristics of the aortic arch and provide basic information for the development of arch-specific endovascular devices.

Materials and methods: Three-dimensional models were reconstructed in Mimics (image segmentation software) from computed tomography aortograms of 120 elderly Asian patients, by manual segmentation. The centerline of each Three-dimensional aortic model was calculated using a repulsive force field method. Measurements of the aorta and supra-aortic branches were analyzed using Patran (finite-element software). A three-dimensional statistical aortic arch model was built using principal component analysis.

Results: The mean diameters of the ascending and descending aorta, and the origins of the innominate, left common carotid, and left subclavian artery were 39.4 ± 6.7, 34.5 ± 7.9, 18.0 ± 3.8, 12.6 ± 2.7, and 14.1 ± 2.5 mm, respectively. The length of the ascending aorta, innominate to left common carotid artery, and left common carotid to left subclavian artery were 62.6 ± 11.4, 12.0 ± 5.6, and 18.7 ± 5.6 mm along the centerline. The mean angle of curvature was 103.8 ± 25 degrees. Principal component analysis of the three-dimensional centerlines derived 3 main modes of variation, which account for 61% of the overall shape range.

Conclusion: Aortic arch anatomical information from an elderly Asian population can be useful for the development of future endovascular devices.

Deployment of proximal thoracic endograft in zone 0 of the ascending aorta: treatment options and early outcomes for aortic arch aneurysms in a high-risk population

OBJECTIVES

Open repair of aortic arch aneurysms can be technically challenging. Hybrid approaches have been developed to facilitate arch repairs and improve their clinical outcomes in high-risk patients. We examined treatment options and early outcomes in patients whose thoracic endografts were deployed to include Zone 0.

METHODS

Between 2005 and 2011, a hybrid approach in which the endograft was deployed in the ascending aorta was used in 29 patients (median age 67 years, range 32-85 years). The indication for surgery was saccular arch aneurysm in 11 patients (37.9%), fusiform arch aneurysm with or without involvement of the proximal descending aorta in 10 (34.5%), proximal Type I endoleak after endovascular repair of the descending aorta in 5 (17.2%), chronic Type III (Type B) aortic dissection with aneurysmal arch formation in 2 (6.9%) and acute Type I (Type A) dissection with prior repair of an extent I thoracoabdominal aneurysm in 1 (3.4%). Six patients (20.7%) had previously undergone a sternotomy. One-, two- or three-branch aortobrachiocephalic de-branching, with or without concomitant heart surgery, was performed in 28 patients and extra-anatomic bypass in 1.

RESULTS

Two patients (6.9%) died during postoperative hospitalization. Overall survival during the follow-up period (median 411 days) was 79.3%. Five neurological events occurred: one extensive stroke, two minor strokes (10.3%) and two episodes of paraparesis (6.9%), one with partial recovery and one with full recovery.

CONCLUSIONS

The hybrid approach enables the treatment of aortic arch disease in high-risk individuals. Long-term follow-up data are needed.

Three-dimensional evaluation of thoracic aorta enlargement and unfolding in hypertensive men using non-contrast computed tomography

Aging produces a simultaneous thoracic aorta (TA) enlargement and unfolding. We sought to analyze the impact of hypertension on these geometric changes. Non-contrast computed tomography images were obtained from coronary artery calcium scans, including the entire aortic arch, in 200 normotensive and 200 hypertensive asymptomatic men. An automated algorithm reconstructed the vessel in three-dimensions, estimating orthogonal aortic sections along the whole TA pathway, and calculated several geometric descriptors to assess TA morphology. Hypertensive patients were older with respect to normotensive (P<0.001). Diameter and volume of TA ascending, arch and descending segments were higher in hypertensive patients with respect to normotensive (P<0.001) and differences persisted after adjustment for age. Hypertension produced an accelerated unfolding effect on TA shape. We found increments in aortic arch width (P<0.001), radius of curvature (P<0.001) and area under the arch curve (P<0.01) with a concomitant tortuosity decrease (P<0.05) and no significant change in aortic arch height. Overall, hypertension produced an equivalent effect of 2-7-years of aging. In multivariate analysis adjusted for age and hypertension treatment, diastolic pressure was more associated to TA size and shape changes than systolic pressure. These data suggest that hypertension accelerates TA enlargement and unfolding deformation with respect to the aging effect.