Zone zero thoracic endovascular aortic repair: A proposed modification to the classification of landing zones

Endovascular Technique for Ascending Aorta Repair Based on TEVAR and TAVI Procedures

PURPOSE

Ascending aorta (AAo) acute pathology still has an open-surgery indication with a high mortality rate associated to cardiopulmonary bypass and circulatory arrest. In these cases, the endovascular aortic approach could be an excellent option. The aim of the present study is to detail an optimized technique for the endovascular treatment of AAo diseases, based on thoracic endovascular aortic repair (TEVAR) and transcatheter aortic valve implantation (TAVI) procedures.

TECHNIQUE

The procedure implies the usual preparation for TEVAR and TAVI implants. A transient pacemaker lead is necessary to deliver the prosthesis under "rapid pacing." As in the TAVI technique, a final high-support guidewire is placed at the left ventricle. The proximal landing zone is the sinotubular junction (zone 0B). Transesophageal echocardiography is essential to ensure aortic valve function and patency in coronary arteries during the delivery. To assess a potential occlusion of the brachiocephalic artery, a guidewire is positioned in the descending aorta from the axillary artery. Finally, a noncovered stent is implanted to stabilize the AAo prosthesis.

CONCLUSION

The technique presented here can standardize a safe and reproducible procedure to endovascular repair of AAo diseases. However, new devices specifically designed for the AAo could facilitate the transcatheter approach.

CLINICAL IMPACT

Ascending aorta acute pathology still has an open-surgery indication with high mortality rate associated to cardiopulmonary bypass and circulatory arrest. Moreover, near 30% of patients are not considered suitable for surgery because of age, critical situation or the presence of severe comorbidities. The present study provides a detailed and optimized technique for the endovascular treatment of ascending aorta disease, based on TEVAR and TAVI procedures.

Aortic diameter is a poor predictor of aortic tissue failure metrics in patients with ascending aneurysms

OBJECTIVES

There is growing consensus that aortic diameter is a flawed predictor of aortic dissection risk. We hypothesized that aortic tissue metrics would be better predicted by clinical metrics other than aortic diameter. Our objectives were to (1) characterize circumferential aortic failure stress and stretch as a result of aortic size and patient demographics, and (2) identify the influence of bicuspid aortic valve on failure metrics.

METHODS

From February 2018 to January 2021, 136 aortic tissue samples were obtained from 86 adults undergoing elective ascending aorta repair. Uniaxial biomechanical testing to failure, defined as a full-thickness central tear, was performed to obtain tissue failure stress and failure stretch and compared with clinical data and preoperative computed tomography imaging. The relationships among aortic diameter, patient demographics, and failure metrics were assessed using random forest regression models.

RESULTS

Median failure stress was 1.46 (1.02-1.94) megapascals, and failure stretch was 1.36 (1.27-1.54). Regression models correlated moderately with failure stress (R2 = 0.557) and highly with failure stretch (R2 = 0.806). Failure stress decreased with increasing age, lower body mass index, thicker tissue, and tricuspid aortic valves, whereas failure stretch was most highly correlated with age. Aortic area-to-height index outperformed aortic diameter in all models.

CONCLUSIONS

Aneurysmal ascending aortic tissue failure metrics correlated with available clinical metrics. Greater tissue thickness, older age, and tricuspid aortic valve morphology outperformed aortic diameter, warranting further investigation into the role of a patient-specific multifactorial dissection risk assessment over aortic diameter as a sole marker of aortic tissue integrity.

Endovascular repair of ascending aortic pathologies in patients unfit for open surgery: case series and literature review

The number of vascular centers performing endovascular repair of ascending aortic disease is constantly increasing. Accordingly to the guidelines, open surgical repair remains the gold standard for these pathologies. However, approximately one quarter of patients are deemed unfit for open surgery. In this study, we describe three cases of ascending thoracic endovascular aortic repair (TEVAR) performed at our center. All the patients were deemed unfit for open surgery by the aortic team. Two patients had an ascending aortic pseudoaneurysm, and the third had a focal type A aortic dissection. In two cases, we used two abdominal aortic cuffs deployed from zone 0B to zone 0C, with no need for supra-aortic trunk debranching. In one case, we performed a "reverse" extrathoracic debranching, and we deployed a thoracic endograft from zone 0B to zone 2. Complications included one minor stroke and one inguinal hematoma. In one patient with an infected pseudoaneurysm, we performed ascending TEVAR as a bridge strategy for open repair. This patient developed a type Ia endoleak; however, clinical stabilization and infection control were obtained, and he was able to undergo heart surgery successfully. He underwent a second reintervention to treat superior mesenteric embolic occlusion. At 2 years of follow-up, all three patients were alive. Our preliminary experience demonstrates the technical feasibility and clinical appropriateness of ascending TEVAR using standard, commercially available endografts. However, no consensus has been reached regarding some critical aspects, such as the development of a standardized technique or the efficacy of the currently available devices. The improvements in graft design and the adoption of the "aortic team" approach could help in the near future to standardize the procedure, establish appropriate indications, and ensure good clinical outcomes.

Endovascular Treatment of Type A Aortic Dissection: A Systematic Review and Meta-Analysis Using Reconstructed Time-to-Event Data

OBJECTIVE

The undisputed gold standard of treatment for type A aortic dissections (TAAD) is open surgery. Anecdotal reports have assessed thoracic endovascular aortic repair (TEVAR) as a last resort for highly selected candidates. The present study aims to evaluate endovascular outcomes in TAAD patients who are unsuitable for open surgery whilst having TEVAR-compatible aortic anatomy.

METHODS

A PRISMA-compliant systematic search of the PubMed, Scopus, and Cochrane databases was performed up to 19 May 2022. Time-to-event data were reconstructed using Kaplan-Meier curves from the source literature.

RESULTS

In 20 eligible studies, 311 patients underwent TEVAR for acute, subacute, or chronic TAAD. Mean age at the time of the operation was 60.70 ± 8.00 years and 75.48% (95% Confidence Interval [CI], 60.33-88.46%) of the included patients were males. Mean operative time was 169.40 ± 30.70 min. Overall, 0.44% (95% CI, 0.00-4.83%) of the cases were converted to salvage open surgery. Technical failure, stroke, and endoleaks occurred in 0.22%, 0.1%, and 8.52% of the cohort, respectively. Thirty-day postoperative complication rate was 7.08% (95% CI, 1.52-14.97%), whereas late complications developed in 16.89% (95% CI, 7.75-27.88%) of the patients. One-, three-, and five-year survival rates were estimated at 87.15%, 82.52% and 82.31%, respectively. Reintervention was required in 8.38% of the cohort over a mean follow-up of 32.40 ± 24.40 months.

CONCLUSIONS

TEVAR seems to be feasible in highly selected patients with TAAD who cannot tolerate open surgery. Overcoming technical limitations and acquiring long-term data are warranted to safely define the place of endovascular treatment in the armamentarium of TAAD repair.

Sex-Specific Morphometric Analysis of Ascending Aorta and Aortic Arch for Planning Thoracic Endovascular Aortic Repair: A Retrospective Cohort Study

OBJECTIVE

In many studies on aortic disease, women are underrepresented. The present study aims to assess sex-specific morphometric differences and gain more insight into endovascular treatment of the ascending aorta (AA) and arch.

METHODS

Electrocardiogram-gated cardiac computed tomography scans of 116 consecutive patients who were evaluated for transcatheter aortic valve replacement were retrospectively reviewed. Measurements of the AA and aortic arch were made in multiplanar views, perpendicular to the semi-automatic centerline. Multiple linear regression analysis was performed to identify predictors affecting AA and aortic arch diameter in men and women. Propensity score matching was used to investigate whether sex influences aortic morphology.

RESULTS

In both sexes, body surface area (BSA) was identified as a positive predictor and diabetes as a negative predictor for aortic diameters. In men, age was identified as a positive predictor and smoking as a negative predictor for aortic diameters. Propensity score matching identified 40 pairs. Systolic and diastolic mean diameters and AA length were significantly wider in men. On average, male aortas were 7.4% wider than female aortas, both in systole and diastole.

CONCLUSIONS

The present analysis demonstrates that, in women, increased BSA is associated with increased aortic arch diameters, while diabetes is associated with decreased AA and arch diameters. In men, increased BSA and age are associated with increased AA and arch diameters, while smoking and diabetes are associated with decreased AA and arch diameters. Men were confirmed to have 7.4% greater AA and arch diameters than women.

CLINICAL IMPACT

Men had 7.4% greater ascending aorta and arch diameters than women in a retrospective cohort, gated computed tomography-based study of 116 patients. Sex-specific differences in ascending aortic and arch size should be considered by aortic endovascular device manufacturers and physicians when developing ascending and arch endografts and planning aortic interventions.

Emergency and Compassionate Use of a Novel Ascending Endograft for Ascending and Arch Aortic Pathology

PURPOSE

Patients with complicated ascending aortic pathology, including patients with acute type A aortic dissection may be at extreme risk for open repair. Thoracic endovascular aortic repair (TEVAR), infrequently used for the ascending aorta, may be considered an alternative in this setting. We describe early results for emergency and compassionate (E&C) use of a novel endograft, specifically designed for use to treat pathology of the ascending aorta.

MATERIALS AND METHODS

This case series evaluated 19 patients (mean age, 68.84±13.12 years; 57.9% female) treated with ascending TEVAR for acute and chronic acute (4), subacute (1), or chronic (1) aortic dissection or pseudoaneurysm (13). Six of the 19 patients (31.5%) were treated under compassionate use and 13 patients (68.4%) were treated under the emergency use exemption. Ten patients (52.6%) received additional devices to extend treatment into the arch and descending aorta.

RESULTS

Device delivery was achieved in all patients (100%). Thirty-day mortality and stroke occurred in 3 patients (15.8%) and in 1 patient (5.3%), respectively. In 1 patient (5.3%), with an Unanticipated Adverse Device Event, the aorta ruptured when the endograft eroded into the adventitial portion of dissection site at the posterior aspect of the ascending wall. Devices were explanted in 2 patients (10.5%), 353 and 610 days after the index procedure, respectively. Six patients had endoleaks (31.6%), including type I (n=2, 10.5%), type II endoleaks (n=3, 15.8%), and indeterminate endoleak (n=1, 5.3%).

CONCLUSIONS

Delivery and deployment of a novel ascending thoracic stent graft with or without an additional branched arch extension is feasible in patients with complex anatomy and pathology, including acute aortic dissection and pseudoaneurysm. Additional experience with this novel device will further refine the patient population most suitable for endovascular ascending aortic repair for these pathologies.

CLINICAL IMPACT

This study describes a novel stent graft specifically designed for treatment of ascending aortic pathology, including acute type A dissection. The patients described in this series constituted a group outside the formal US FDA sponsored clinical trial, and were those accepted as part of an emergency and compassionate use basis.

2022 ACC/AHA guideline for the diagnosis and management of aortic disease: A report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

Ex vivo biaxial load testing analysis of aortic biomechanics demonstrates variation in elastic energy distribution across the aortic zone zero

OBJECTIVES

We hypothesized that tissue characteristics vary significantly along zone zero, which may be reflected by regional differences in stored elastic energy. Our objectives were to (1) characterize the regional variation in stored elastic energy within tissues of the aortic zone zero and (2) identify the association between this variation and patient characteristics.

METHODS

From February 2018 to January 2021, 123 aortic tissue samples were obtained from the aortic root and proximal and distal ascending aortas of 65 adults undergoing elective ascending aorta replacement. Biaxial biomechanics testing was performed to obtain tissue elastic energy at the inflection point and compared with patient demographics and preoperative computed tomography imaging. Coefficient models were fit using B-spline to interrogate the relationship among elastic energy, region, and patient characteristics.

RESULTS

Mean elastic energy at inflection point was 24.3 ± 15.6 kJ/m3. Elastic energy increased significantly between the root and proximal, and root and distal ascending aorta and decreased with increasing age. Differences due to history of connective tissue disorder and bicuspid aortic valve were significant but diminished when controlled for other patient characteristics. Among covariates, age and region were found to be the most important predictors for elastic energy.

CONCLUSIONS

Aortic tissue biomechanical metrics varied across regions and with patient characteristics within the aortic zone zero. Assessment of endovascular outcomes in the ascending aorta must closely consider the region of deployment and variable tissue qualities along the length of the landing zone. Regional variation in tissue characteristics should be incorporated into existing patient-specific models of aortic mechanics.

Ascending Aortic Endograft and Thoracic Aortic Deformation After Ascending Thoracic Endovascular Aortic Repair

PURPOSE

We aim to quantify multiaxial cardiac pulsatility-induced deformation of the thoracic aorta after ascending thoracic endovascular aortic repair (TEVAR) as a part of the GORE ARISE Early Feasibility Study.

MATERIALS AND METHODS

Fifteen patients (7 females and 8 males, age 73±9 years) with ascending TEVAR underwent computed tomography angiography with retrospective cardiac gating. Geometric modeling of the thoracic aorta was performed; geometric features including axial length, effective diameter, and centerline, inner surface, and outer surface curvatures were quantified for systole and diastole; and pulsatile deformations were calculated for the ascending aorta, arch, and descending aorta.

RESULTS

From diastole to systole, the ascending endograft exhibited straightening of the centerline (0.224±0.039 to 0.217±0.039 cm^-1, p<0.05) and outer surface (0.181±0.028 to 0.177±0.029 cm^-1, p<0.05) curvatures. No significant changes were observed for inner surface curvature, diameter, or axial length in the ascending endograft. The aortic arch did not exhibit any significant deformation in axial length, diameter, or curvature. The descending aorta exhibited small but significant expansion of effective diameter from 2.59±0.46 to 2.63±0.44 cm (p<0.05).

CONCLUSION

Compared with the native ascending aorta (from prior literature), ascending TEVAR damps axial and bending pulsatile deformations of the ascending aorta similar to how descending TEVAR damps descending aortic deformations, while diametric deformations are damped to a greater extent. Downstream diametric and bending pulsatility of the native descending aorta was muted compared with that in patients without ascending TEVAR (from prior literature). Deformation data from this study can be used to evaluate the mechanical durability of ascending aortic devices and inform physicians about the downstream effects of ascending TEVAR to help predict remodeling and guide future interventional strategies.

CLINICAL IMPACT

This study quantified local deformations of both stented ascending and native descending aortas to reveal the biomechanical impact of ascending TEVAR on the entire thoracic aorta, and reported that the ascending TEVAR muted cardiac-induced deformation of the stented ascending aorta and native descending aorta. Understanding of in vivo deformations of the stented ascending aorta, aortic arch and descending aorta can inform physicians about the downstream effects of ascending TEVAR. Notable reduction of compliance may lead to cardiac remodeling and long-term systemic complications. This is the first report which included dedicated deformation data regarding ascending aortic endograft from clinical trial.

Lengthwise regional mechanics of the human aneurysmal ascending thoracic aorta

The prognosis of patients undergoing emergency endovascular repair of ascending thoracic aortic aneurysm (ATAA) depends on defect location, with root disease bearing worse outcomes than proximal or distal aortopathy. We speculate that a spatial gradient in aneurysmal tissue mechanics through the length of the ascending thoracic aorta may fuel noted survival discrepancies. To this end, we performed planar biaxial testing on 153 root, proximal, and distal segments of ATAA samples collected from 80 patients receiving elective open surgical repair. Following data averaging via surface fitting-based interpolation of strain-controlled protocols, we combined in-vitro and in-vivo measurements of loads and geometry to resolve inflation-extension kinematics and evaluate mechanical metrics of stress, stiffness, and energy at consistent deformation levels. Representative (averaged) experimental data and simulated in-vivo conditions revealed significantly larger biaxial stiffness at the root compared to either proximal or distal tissues, which persisted as the entire aorta stiffened during aging. Advancing age further reduced biaxial stretch and energy storage, a measure of aortic function, across all ATAA segments. Importantly, age emerged as a stronger predictor of tissue mechanics in ATAA disease than either bicuspid aortic valve or connective tissue disorders. Besides strengthening the general understanding of aneurysmal disease, our findings provide specifications to customize the design of stent-grafts for the treatment of ATAA disease. Optimization of deployment and interaction of novel endovascular devices with the local native environment is expected to carry significant potential for improving clinical outcomes. STATEMENT OF SIGNIFICANCE: Elucidating the lengthwise regional mechanics of ascending thoracic aortic aneurysms (ATAAs) is critical for the design of endovascular devices tailored to the ascending aorta. Stent-grafts provide a less invasive alternative to support the long-term survival of ATAA patients ineligible for open surgical repair. In this study, we developed a numerical framework that combines semi-inverse constitutive and forward modeling with in-vitro and in-vivo data to extract mechanical descriptors of ATAA tissue behavior at physiologically meaningful deformation. Moving distally from the aortic root to the first ascending aortic branch, we observed a progressive decline in biaxial stiffness. Furthermore, we showed that aging leads to reduced aortic function and is a stronger predictor of mechanics than either valve morphology or underlying syndromic disorder.

NEXUS Arch: A Multicenter Study Evaluating the Initial Experience With a Novel Aortic Arch Stent Graft System

OBJECTIVE

To assess the initial clinical experience with a novel endograft system (NEXUS Aortic Arch Stent Graft System) designed to treat aortic arch pathologies and address the morphology and hemodynamic challenges of the aortic arch.

SUMMARY BACKGROUND DATA

The aortic arch remains the most challenging part of the aorta for both open and endovascular repair. Transcatheter aortic arch repair has the potential to significantly reduce surgical risks.

METHODS

Patients underwent transcatheter aortic arch repair with a single branch, 2 stent graft system, implanted over a through-and-through guidewire from the brachiocephalic trunk, to the descending aorta with an ascending aorta stent graft. The ascending aorta stent graft is deployed into a designated docking sleeve to connect the 2 stent grafts and isolate the aortic arch pathology. Proximal landing zone in all cases was in Zone 0. Anatomical inclusion criteria included adequate landing zone in the ascending aorta, brachiocephalic trunk, and descending thoracic aorta. Preparatory debranching procedure was performed in all patients with carotid-carotid crossover bypass and left carotid to left subclavian bypass, or parallel graft from descending aorta to left subclavian artery. Safety and performance were evaluated through 1 year. Survival analysis used the Kaplan-Meier method.

RESULTS

Twenty-eight patients, 79% males, with a mean age of 72.2 ± 6.2 years were treated with 100% procedural success. Isolated aortic arch aneurysm was the principle pathology in 17 (60.7%) of patients, while chronic aortic dissection was the principle pathology in 6 (21.4%) of patients. The remaining 5 (17.8%) had combined or other pathologies. At 1 month, the vascular pathology was excluded in 25 of 26 alive patients (96.1%). The 30 days mortality rate was 7.1%, stroke rate was 3.6% (all nondisabling), and combined mortality/stroke rate was 10.7%. One-year mortality was 10.7%, without device or aneurysm-related death. Two patients (7.1%) reported stroke or transient ischemic attack at 1 year that recovered completely. One year combined mortality/stroke rate was 17.8%. There were 3 patients (10.7%) that had device-related unplanned reinterventions through 1 year.

CONCLUSIONS

The NEXUS Aortic Arch Stent Graft System, a novel single branch, 2 stent graft system used for endovascular aortic arch repair that requires landing in the ascending aorta, demonstrates a high success rate with excellent 1 year safety and performance.

A systematic review and meta-analysis of thoracic endovascular aortic repair with the proximal landing zone 0

Background

Thoracic endovascular aortic repair, initially intended for thoracic aortic disease treatment, has extended its application to the proximal zone of the aorta. However, the safety and surgical outcomes of extending the proximal landing zone into the ascending aorta (zone 0) in selected cases remain unknown. Thus, we performed a systematic review and meta-analysis of zone 0 thoracic endovascular aortic repair (TEVAR) to obtain a deeper understanding of its safety, outcomes, and trends over time.

Methods

A literature search was performed using PubMed, EMBASE, and Web of Science databases in accordance with the preferred reporting items for systematic reviews and meta-analyses guidelines, from January, 1997 to January, 2022. Only studies involving zone 0 TEVAR were included. The retrieved data from the eligible studies included basic study characteristics, 30-day/in-hospital mortality rate, indications, comorbidities, stent grafts, techniques, and complications. Summary effect measures of the primary outcomes were obtained by logarithmically pooling the data with an inverse variance-weighted fixed-effects model.

Results

Fifty-three studies with 1,013 patients were eligible for analysis. The pooled 30-day/in-hospital mortality rate of zone 0 TEVAR was 7.49%. The rates of post-operative stroke, type Ia endoleak, retrograde type A aortic dissection, and spinal cord ischemia were 8.95, 9.01, 5.72, and 4.12%, respectively.

Conclusions

Although many novel stent grafts and techniques targeting zone 0 TEVAR are being investigated, a consensus on technique and device selection in zone 0 TEVAR is yet to be established in current practice. Furthermore, the post-operative stroke rate is relatively high, while other complication rates and perioperative death rate are comparable to those of TEVAR for other aortic zones.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate. Structure: Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

The impact of prophylactic ascending aortic replacement on the long-term prognosis of hybrid arch repair

OBJECTIVES

To investigate the impact of prophylactic zone 0 replacement with prosthetic grafts on the long-term prognosis and perioperative safety of zone 0 hybrid arch repair (HAR) when zone 0 is neither dilated nor pathologic.

METHODS

115 patients whose zone 0 aorta was neither dilated nor pathologic and who underwent zone 0 HAR from January 2009 to December 2020 were retrospectively reviewed, and divided into two groups depending on whether zone 0 was replaced, with 46 patients in the no-replacement group and 69 patients in the replacement group. Inverse probability of treatment weighting (IPTW) was used to balance the baseline difference, and outcomes were compared after IPTW adjustment. The primary endpoints were overall survival and adverse aortic events (AAEs). The secondary endpoints were early composite adverse events and other perioperative complications. Subgroup analysis was performed by age, diagnosis, zone 0 maximum diameter and risk stratification.

RESULTS

The 5-year IPTW-adjusted overall survival rate was 84% in the no-replacement group, 90% in the replacement group, respectively (P=.61). With death as a competing risk, the IPTW-adjusted cumulative incidence of AAEs at 5 and 10 years was 23% and 41% in the no-replacement group, and 14% and 25% in the replacement group, respectively (sHR=0.56, 95%CI=0.23∼1.39; P=.23). Considering proximal complications alone, the replacement group exhibited lower 5-year (3% vs 18%) and 10-year (6% vs 36%) cumulative incidences of proximal complications (sHR=0.11, 95%CI=0.01∼0.91, P=.04) after IPTW adjustment. Subgroup analysis demonstrated that the benefits of zone 0 replacement in reducing AAEs were observed in the age≤60-year-old (sHR=0.15, 95%CI=0.03∼0.75, P=.02) and type B aortic dissection (TBAD) (sHR=0.24, 95%CI=0.07∼0.82, P=.02) subgroups. Additionally, zone 0 replacement did not increase early composite adverse event morbidity (9% vs 21%, P=.08) or early mortality (7% vs 6%, P=.87).

CONCLUSIONS

Although zone 0 was neither dilated nor pathologic, prophylactic zone 0 replacement in zone 0 HAR significantly reduced the incidence of proximal complications, without impairing perioperative safety. Additionally, this strategy was associated with benefits in reducing AAEs in younger and TBAD patients. Thus, prophylactic zone 0 replacement should be considered for reconstructing a stable proximal landing zone in zone 0 HAR.

ARISE: First-In-Human Evaluation of a Novel Stent Graft to Treat Ascending Aortic Dissection

BACKGROUND

Operative mortality for type A aortic dissection is still 10-20% at centers of excellence. Additionally, 10-20% are not considered as viable candidates for open surgical repair and not offered life-saving emergency surgery. ARISE is a multicenter investigation evaluating the novel GORE® Ascending Stent Graft (ASG; Flagstaff, AZ).

OBJECTIVE

The purpose of this study is to assess early feasibility of using these investigational devices to treat ascending aortic dissection.

METHODS

This a prospective, multicenter, non-randomized, single-arm study that enrolls patients at high surgical risk with appropriate anatomical requirements based on computed tomography imaging at 7 of 9 US sites. Devices are delivered transfemorally under fluoroscopic guidance. Primary endpoint is all-cause mortality at 30 days. Secondary endpoints include major adverse cardiovascular and cerebrovascular events (MACCE) at 30 days, 6 months, and 12 months.

RESULTS

Nineteen patients were enrolled with a mean age of 75.7 years (range 47-91) and 11 (57.9%) were female. Ten (52.6%) had DeBakey type I disease, and the rest were type II. Sixteen (84.2%) of the patients were acute. Patients were treated with safe access, (7/19 (36.8%) percutaneous, 10/19 (52.6%) transfemoral, 2/19 (10.5%) iliac conduit), delivery, and deployment completed in all cases. Median procedure time was 154 mins (range 52-392) and median contrast used was 111 mL (range 75-200). MACCE at 30 days occurred in 5 patients including mortality 3/19 (15.8%), disabling stroke in 1/19 (5.3%), and myocardial infarction in 1/19 (5.3%).

CONCLUSION

Results from the ARISE early feasibility study of a specific ascending stent graft device to treat ascending aortic dissection are promising.

Endovascular Repair for Ascending Aortic Graft Side Branch Pseudoaneurysm: A Report of Two Cases

Introduction

A pseudoaneurysm arising from the side branch of the prosthesis, following ascending aortic replacement, is extremely rare. Re-intervention usually involves open surgery, replacement of the ascending aorta, or ligation of the side branch. Redo surgery with an additional sternotomy carries the risk of cardiac and vascular injuries, and endovascular treatment can reduce such adverse events.

Report

This study describes the successful thoracic endovascular aortic repair (TEVAR) of two cases of pseudoaneurysms arising from the side branch after ascending aortic replacement. Case 1 involved a 79 year old man who underwent ascending aortic replacement and omentopexy for a ruptured tuberculous aortic aneurysm 13 years ago. The pseudoaneurysm was mushroom shaped with a 30 mm protrusion. Case 2 involved an 83 year old man who underwent ascending aortic replacement for Stanford type A acute aortic dissection 11 years ago. The pseudoaneurysm was rod shaped with a 27 mm protrusion. In both cases, the pseudoaneurysm arising from the side branch was not noted on computed tomography (CT) until one year earlier and was first identified at a routine follow up examination. The pseudoaneurysms required surgical repair because of the risk of rupture; however, TEVAR was selected considering the risks of redo surgery and the patients' ages. It was performed via a femoral artery approach without adverse events using a commercially available thoracic aortic device. Post-operative CT scan showed complete exclusion of the pseudoaneurysm.

Discussion

Although TEVAR is usually not indicated for ascending aortic pathologies, if there is an anatomical indication and a compatible stent graft, TEVAR for the ascending aorta should be the first choice in patients who are inoperable, at high risk and undergoing redo surgery.

Towards Endovascular Treatment of Type A Aortic Dissection with Smaller Landing Zones and More Patient Eligibility

OBJECTIVE

Type A or ascending aortic dissection is an acute life-threatening condition with high morbidity and mortality. Open surgery remains standard-of-care. Development of minimally invasive endografts for Type A aortic dissection (TAAD) will require detailed understanding of dissection and aortic root anatomy to determine patient eligibility and optimal device specifications.

METHODS

Computed tomography images of TAAD cases at our institution from 2012-2019 were identified and three-dimensional reconstructions were performed using OsiriX 10.0 (Bernex, Switzerland). Analysis of key anatomic structures including centerline length measurements, ascending aorta/aortic root dimensions, as well as location and extent of dissection were determined in relation to coronary ostia.

RESULTS

A total of 53 patients were identified (mean±SD age 60.4±17.1 years; 36 male, 17 female), 46 of whom underwent surgery for TAAD. Four patients died within 30 days of surgery. In 47 patients (88.7%), the entry tear was distal to the highest coronary ostium. These cases were retrospectively considered for endovascular intervention with a non-branched, single endograft stent. Proximal landing zone (LZ) was defined as distance from the highest coronary ostium to entry tear: 35/53 (66.0%) had a proximal LZ length ≥2.0cm, 38/53 (71.7%) had proximal LZ length ≥1.5cm, and 42/53 (79.2%) had proximal LZ length ≥1.0cm. Proximal and distal LZ diameters of the sinotubular junction (STJ) and distal ascending aorta regions were (median [1^st quartile-3^rd quartile]) 3.29cm [2.73-4.10cm] and 3.49cm [3.09-3.87cm], respectively, with length from STJ to innominate takeoff 8.08cm [6.96-9.40cm]. Ascending aorta radius of curvature was 6.48cm [5.27-8.00cm]. 47.2% (25/53) of patients could be treated with a straight tube graft with ≤20% diameter mismatch between the proximal and distal LZ.

CONCLUSIONS

Almost 80% of patients with TAAD had a proximal LZ ≥1.0cm, and of these, 47.2% had anatomy amenable to endovascular therapy with a non-tapered straight tube graft commercially available devices. To increase patient eligibility for TAAD endovascular intervention, enhanced precision deployment with adequate seal in shorter LZs will be required. Our results serve as a guide for endovascular device specifications designed to treat this devastating condition.

Outcomes of Total Endovascular Aortic Arch Repair with Surgeon-Modified Fenestrated Stent-Grafts on Zone 0 Landing for Aortic Arch Pathologies

OBJECTIVES

This study evaluated the feasibility and safety of total endovascular aortic arch repair with surgeon-modified fenestrated stent-graft on zone 0 landing for aortic arch pathologies.

METHODS

Between June 2016 and October 2019, 37 consecutive patients underwent total endovascular arch repair with surgeon-modified fenestrated stent-grafts on zone 0 landing. Outcomes included technical success, perioperative and follow-up morbidity and mortality, and branch artery patency.

RESULTS

During the study period, 37 patients were treated with total endovascular aortic arch repair with surgeon-modified fenestrated stent-graft. Twenty-one (56.8%) patients were diagnosed with aortic dissections, 15 (40.5%) patients with aneurysms, and 1 (2.7%) patient required reintervention due to endoleak and sac expansion from previous thoracic endovascular aortic repair for thoracoabdominal aneurysm. The proximal landing zone for all patients were in zone 0, and all branch arteries of aortic arch were reconstructed. Technical success was achieved in 34 cases (91.9%). Three (8.1%) patients had fenestrations misaligned with target arteries, and the chimney technique was applied as a complementary measure. Thirty-day mortality rate was 5.4% (n=2). Thirty-day stroke rate was 5.4% (n=2). Thirty-day reintervention rate was 2.7% (n=1). At a median follow-up of 20 months (range, 3-49 months), 5 (13.5%) patients died, including 2 aortic-related deaths, 1 nonaortic-related death, and 2 deaths of unknown reason. One (2.7%) patient had stroke. Four patients (10.8%) had reintervention during the follow-up, including 2 cases of left subclavian artery occlusion and 2 cases of type II endoleak. The estimated survival (±SE) at 2 years was 72.4%±9.7% (95% CI 53.4%-91.4%). The estimated freedom from reintervention (±SE) at 2 years was 87.4%±5.9% (95% CI 75.84%-98.96%).

CONCLUSIONS

Total endovascular aortic arch repair with surgeon-modified fenestrated stent-grafts on zone 0 landing is an alternate option for the treatment of aortic arch pathologies in experienced centers.

Computed Tomography Imaging of Aortic Dissections with Endovascular Treatment Considerations

PURPOSE OF REVIEW

In the present review, we discuss the role of CT imaging in the management of aortic dissection, with a particular emphasis on endovascular treatment considerations.

RECENT FINDINGS

Computed tomography imaging is a fundamental tool in the diagnosis and management of acute and chronic aortic dissection. Its diagnostic accuracy and high resolution contribute to and guide operative strategy. Persistent high mortality for patients who develop aortic dissections suggests a need for innovative diagnostic and treatment strategies. In the recent era, considerable advances have been made in computed tomography (CT) image acquisition, processing, and analysis as well as endovascular technologies with expanded roles in the treatment of aortic diseases.

Endovascular repair of ascending aortic diseases with custom-made endografts

OBJECTIVES

The aim of this article is to report the mid-term results of ascending thoracic endovascular aortic repair using a custom-made device (CMD).

METHODS

This was a retrospective study performed at tertiary centres. Nine patients considered unfit for open surgery received elective total endovascular repair of the ascending aorta with a Relay® (Terumo Aortic, Sunrise; FL, USA) CMD: pseudoaneurysn (n = 5), localized dissection (n =3) and contained rupture (n = 1).

RESULTS

Primary clinical success was achieved in all patients with no major complications and no early conversion to open surgery. All patients were discharged home and independent: median length of stay was 7 days (interquartile range, 6-18). No patient was lost to follow-up at a median 26 months (interquartile range, 12-36). Three patients died 2, 6 and 24 months after intervention; 1 was aorta related (late aorto-atrial fistula due to infection that required open surgery). At the last follow-up available, no endoleaks, migrations, fractures or ruptures were observed in the remaining 6 patients.

CONCLUSIONS

Ascending thoracic endovascular aortic repair with Terumo Aortic CMDs was technically feasible, effective and safe in very selected lesions. CMDs showed good ascending aorta conformability with different configurations and diameters, and satisfactory mid-term durability as shown by both structural integrity and aortic lesion exclusion.

Back-Table Modified Stent-Graft for Endovascular Repair of Ascending Aorta

OBJECTIVES

To investigate the effectiveness of modified stent-grafts (SGs) for the management of ascending aortic pathologies.

MATERIALS AND METHODS

From January 2015 to December 2019, 31 individuals were treated by ascending aortic endovascular repair with a back-table modified SG for acute (n=4) or chronic (n=1) type A aortic dissections, penetrating aortic ulcers (n=18), pseudoaneurysms (n=2), anastomotic fistula (n=1), and endoleaks after thoracic endovascular aortic repair (TEVAR) (n=5). The commercially available thoracic aortic SGs were modified with a fenestration or truncation technique on the back-table according to aortography during the operation.

RESULTS

The 30-day mortality and aorta-related mortality rates were 12.9% and 6.5%, respectively. There were 2 strokes, 3 respiratory insufficiencies, and 6 endoleaks during hospitalization. During a mean follow-up of 28.8±16.6 months, the overall survival rates at 1 year and 3 years were both 80.6%. Free from adverse event rates at 1 year and 3 years were 88.9% and 84.7%, respectively. There were 2 deaths during follow-up: One patient died of cachexia 1 month after discharge, and the other patient died of acute myocardial infarction 3 months after discharge. One patient with a pseudoaneurysm underwent open ascending aorta replacement 3 months after discharge for a type Ia endoleak. Another patient suffered from cerebellar infarction 17 months after discharge.

CONCLUSION

The modified SG for endovascular repair of the ascending aorta is a practicable alternative and presents acceptable outcomes in high-risk patients.

Anesthetic Considerations in Endovascular Repair of the Ascending Aorta

Since the first endovascular aortic repair in 1990, endovascular devices and the indications for their use have significantly grown. Considerable progress has been made in endovascular devices and techniques, such that endovascular repair is now considered first-line treatment for patients with descending aortic disease. However, for patients with ascending aortic disease, open surgical repair with cardiopulmonary bypass and hypothermic cardiac arrest was the only option until recently. Although the outcomes for open surgical repair of the ascending aorta have improved over the years, approximately 30% of patients with an emergent surgical indication, such as type A aortic dissection, are considered to be too high risk for open repair. For these patients, endovascular repair of the ascending aorta offers a life-saving procedure. The ascending aorta is regarded as the final frontier for endovascular therapy. Endovascular repair of it has posed a formidable challenge thus far, due to its unique anatomy, hemodynamic forces, and lack of an appropriate stent-graft designed specifically for the ascending aorta. Although currently there are no comprehensive data from randomized clinical trials, there are several case series and case reports that have shown favorable outcomes. Improvements in available devices soon will drive an exponential increase in the number of patients undergoing endovascular ascending aortic repair. In this review, the authors discuss multiple aspects of endovascular ascending aortic repair including the unique surgical and anesthetic considerations, the devices used, and the available outcomes data, and future directions are also explored.

Systematic review and meta-analysis of endovascular interventions for Stanford type A aortic dissection

OBJECTIVE

The standard surgical approach to Stanford type A aortic dissection is open repair. However, up to one in four patients will be declined surgery because of prohibitive risk. Patients who are treated nonoperatively have an unacceptably high mortality. Endovascular repair of the ascending aorta is emerging as an alternative treatment for a select group of patients. The reported rates of technical success, mortality, stroke, and reintervention have varied. The objective of the study was to systematically report outcomes for acute type A dissections repaired using an endovascular approach.

METHODS

The systematic review and meta-analysis was conducted in accordance with the PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines. We performed online literature database searches through April 2020. The demographic and procedural characteristics of the individual studies were tabulated. Data on technical success, short-term mortality, stroke, and reintervention were extracted and underwent meta-analysis using a random effects model.

RESULTS

Fourteen studies with 80 cases of aortic dissection (55 acute and 25 subacute) were included in the final analysis. A wide variation was found in technique and device design across the studies. The outcomes rates were estimated at 17% (95% confidence interval [CI], 10%-26%) for mortality, 15% (95% CI, 8%-23%) for technical failure, 11% (95% CI, 6%-19%) for stroke and 18% (95% CI, 9%-31%) for reintervention. The mean Downs and Black quality assessment score was 13.9 ± 3.2.

CONCLUSION

The technique for endovascular repair of type A aortic dissection is feasible and reproducible. The results of our meta-analysis demonstrate an acceptable safety profile for inoperable patients who otherwise would have an extremely poor prognosis. Data from clinical trials are required before the technique can be introduced into routine clinical practice.

Acute Aortic Syndrome of Ascending Thoracic Aorta: Transcarotid Percutaneous Exclusion of a Ruptured Pseudoaneurysm

Treatment of ascending aorta disease is surgical; however, some series have evaluated the effectiveness of endovascular treatment. We report the case of a patient with a ruptured pseudoaneurysm who underwent endovascular repair via the left common carotid artery. The clinical and neurological evolution was satisfactory during the in-hospital follow-up. (Level of Difficulty: Intermediate.).

Finite element modeling to predict procedural success of thoracic endovascular aortic repair in type A aortic dissection

Objective

Thoracic endovascular aortic repair (TEVAR) is recommended for type B aortic dissection and recently has even been used in selected cases of proximal (Stanford type A) aortic dissections in scenarios of prohibitive surgical risk. However, mechanical interactions between the native aorta and stent-graft are poorly understood, as some cases ended in failure. The aim of this study is to explore and better understand biomechanical changes after TEVAR and predict the result via virtual stenting.

Methods

A case of type A aortic dissection was considered inoperable and selected for TEVAR. The procedure failed due to stent-graft migration even with precise deployment. A novel patient-specific virtual stent-graft deployment model based on finite element method was employed to analyze TEVAR-induced changes under such conditions. Two landing positions were simulated to investigate the reason for stent-graft migration immediately after TEVAR and explore options for optimization.

Results

Simulation of the actual procedure revealed that the proximal bare metal stent pushed the lamella into the false lumen and led to further stent-graft migration during the launch phase. An alternative landing position has reduced the local deformation of the dissection lamella and avoided stent-graft migration. Higher maximum principal stress (>20 KPa) was found on the lamella with deployment at the actual position, while the alternative strategy would have reduced the stress to <5 KPa.

Conclusions

Virtual stent-graft deployment simulation based on finite element model could be helpful to both predict outcomes of TEVAR and better plan future endovascular procedures.

Important longitudinal and circumferential pulsatile changes in zone 0 of the aorta during the cardiac cycle

OBJECTIVES

Correct stent-graft sizing is important when planning for thoracic endovascular repair in zone 0. As the movements of the aorta are constantly evolving in longitudinal and circumferential directions during the cardiac cycle, the diameter may not be the only important measurement. The aim of this study is to measure the circumferential and longitudinal pulsatile changes throughout the cardiac cycle.

METHODS

Ninety-two patients, who were evaluated for transcatheter aortic valve replacement, were selected for this retrospective study. Their electrocardiogram-gated cardiac computed tomography was analysed. We identified the area, perimeter and diameter of the thoracic aorta in zone 0 and calculated the differences between these parameters at 3 locations in zone 0. The measurements were made in multiplanar views perpendicular to the semi-automatically created centreline in both systolic and diastolic phases.

RESULTS

The mean age of our study cohort was 77 ± 11 years. The mean change between systole and diastole of the area (mm2), perimeter (mm) and diameter (mm) were compared at 3 different locations in the ascending aorta: at the sinotubular junction (0.78 mm2 vs 0.89 mm vs 1.41 mm), mid-ascending (0.72 mm2 vs 0.68 vs 0.81 mm) and proximal edge of the brachiocephalic artery (0.76 mm2 vs 0.73 mm vs 0.73 mm). The change in percentage is the smallest in the area at the sinotubular junction compared to the perimeter and diameter (2.6% vs 3.1% vs 4.7%).

CONCLUSIONS

Changes in measurement of ascending aortic diameter with cardiac cycle are larger than measurement change in the area. This is especially more pronounced in zone 0A. For more accurate information on the morphometric changes, it may be necessary to measure the area when planning for thoracic endovascular repair to maximize results. A prospective study comparing these different measurements regarding the outcomes is advised by the authors to understand the clinical implications.

Thoracic aortic surgery: status and upcoming novelties

Several novel technological developments and surgical approaches have characterized the field of aortic surgery in the recent decade. The progressive introduction of endovascular procedures, minimally invasive surgical techniques and hybrid approaches have changed the practice in aortic surgery and generated new trends and questions. Also, the advancements in the manufacturing of tissue engineered vascular grafts as substitutes for aortic replacements are enlightening new avenues in the treatment of aortic disease. This review will provide an overview of the current novel perspectives, debates and trends in major thoracic aortic surgery.

Endovascular Treatment of the Ascending Aorta: is this the Last Frontier in Aortic Surgery?

Regardless the successful treatment of the descending aorta with endovascular prosthesis, for the ascending aorta segment, because of several anatomic and physiologic issues, this technique has been considered an alternative only for high-risk or inoperable patients. Despite restricted indications, hundreds of treatments have been performed worldwide, demonstrating its safety and reproducibility if it is done in high-quality centers. Therefore, understanding patients' selection criteria and technique limitations are critical to its application.

Urgent retrograde two-stage hybrid repair of a complicated blunt traumatic aortic injury

Blunt traumatic aortic injury (BTAI) is a rare but life-threatening emergency that is usually caused by sudden acceleration/deceleration injuries in vehicular accidents. We describe our initial experience of a retrograde two-stage hybrid treatment approach for the emergent management of a 63-year-old motorcyclist who presented with a complicated BTAI with malperfusion syndrome. To our best knowledge, this uncommon BTAI case with fatal distal malperfusion saved by an urgent retrograde two-stage hybrid procedure has been reported rarely. This early reperfusion strategy with two-stage retrograde endovascular technique could be an effective and life-saving treatment option for polytrauma patients with suitable aortic anatomy.

Replacing the ascending aorta in the elderly: do or do not

Advanced age is a proven independent factor for perioperative morbidity and mortality in all forms of aortic surgery and forms an important variable in most available risk scores. Improvements in selection and perioperative management of high-risk elderly cohorts have reduced the incidence of adverse outcomes. Concerns remain however in the surgical and anesthesiology community that exposing elderly frail patients to ascending aortic surgery is associated with significant risk. As with many clinical scenarios, individualization of care for each patient is of paramount importance. With advances in our understanding of perioperative and intraoperative care, age should no longer be considered in isolation as a contraindication to ascending aortic surgery.

Are We There Yet? Emerging Milestones in Aortic Dissection Care

See Article Reutersberg et al.

Primary Endovascular Repair of the Ascending Aorta

Different case series have been published demonstrating the feasibility of endovascular repair of the ascending aorta in selected patients deemed unfit for open surgery. However, the use of commercially available stent graft in the ascending aorta remains off-label, and their excessive length often prevents their deployment in the ascending aorta. Here we report a case of successful primary endovascular repair of the ascending aorta using a physician modified off-the-shelf device.