INvestigation of STEnt grafts in patients with type B Aortic Dissection: design of the INSTEAD trial--a prospective, multicenter, European randomized trial

Long-term outcomes of TEVAR for thoracic aortic diseases: a retrospective single-center study

BACKGROUND

The outcomes of Thoracic Endovascular Aortic Repair (TEVAR) vary depending on thoracic aortic pathologies, comorbidities. This study presents our comprehensive endovascular experience, focusing on exploring the outcome in long term follow-up.

METHODS

From 2006 to 2018, we conducted TEVAR on 97 patients presenting with various aortic pathologies. This retrospective cohort study was designed primarily to assess graft durability and secondarily to evaluate mortality causes, complications, reinterventions, and the impact of comorbidities on survival using Kaplan-Meier and Cox regression analyses.

RESULTS

The most common indication was thoracic aortic aneurysm (n = 52). Ten patients had aortic arch variations and anomalies, and the bovine arch was observed in eight patients. Endoleaks were the main complications encountered, and 10 of 15 endoleaks were type I endoleaks. There were 18 reinterventions; the most of which was TEVAR (n = 5). The overall mortality was 20 patients, with TEVAR-related causes accounting for 12 of these deaths, including intracranial bleeding in three patients. Multivariant Cox regression revealed chronic renal diseases (OR = 11.73; 95% CI: 2.04-67.2; p = 0.006), previous cardiac operation (OR = 14.26; 95% CI: 1.59-127.36; p = 0.01), and chronic obstructive pulmonary diseases (OR = 7.82; 95% CI: 1.43-42.78; p = 0.001) to be independent risk factors for 10-year survival. There was no significant difference in the survival curves of the various aortic pathologies. In the follow-up period, two non-symptomatic intragraft thromboses and one graft infection were found.

CONCLUSION

Comorbidities can increase the risk of TEVAR-related mortality without significantly impacting endoleak rates. TEVAR is effective for severe aortic pathologies, though long-term graft durability may be compromised by its thrombosis and infection.

Initial Thoracic Endovascular Aortic Repair vs Medical Therapy for Acute Uncomplicated Type B Aortic Dissection

Importance

Thoracic endovascular aortic repair (TEVAR) has increasingly been used for uncomplicated type B aortic dissection (uTBAD) despite limited supporting data.

Objective

To assess whether initial TEVAR following uTBAD is associated with reduced mortality or morbidity compared with medical therapy alone.

Design, Setting, and Participants

This cohort study included Centers for Medicare & Medicaid Services inpatient claims data for adults aged 65 years or older with index admissions for acute uTBAD from January 1, 2011, to December 31, 2018, with follow-up available through December 31, 2019.

Exposures

Initial TEVAR was defined as TEVAR within 30 days of admission for acute uTBAD.

Main Outcomes and Measures

Outcomes included all-cause mortality, cardiovascular hospitalizations, aorta-related and repeated aorta-related hospitalizations, and aortic interventions associated with initial TEVAR vs medical therapy. Propensity score inverse probability weighting was used.

Results

Of 7105 patients with eligible index admissions for acute uTBAD, 1140 (16.0%) underwent initial TEVAR (623 [54.6%] female; median age, 74 years [IQR, 68-80 years]) and 5965 (84.0%) did not undergo TEVAR (3344 [56.1%] female; median age, 76 years [IQR, 69-83 years]). Receipt of TEVAR was associated with region (vs South; Midwest: adjusted odds ratio [aOR], 0.66 [95% CI, 0.53-0.81]; P < .001; Northeast: aOR, 0.63 [95% CI, 0.50-0.79]; P < .001), Medicaid dual eligibility (aOR, 0.76; 95% CI, 0.63-0.91; P = .003), hypertension (aOR, 1.26; 95% CI, 1.03-1.54; P = .03), peripheral vascular disease (aOR, 1.24; 95% CI, 1.02-1.49; P = .03), and year of admission (2012, 2013, 2014, and 2015 were associated with greater odds of TEVAR compared with 2011). After inverse probability weighting, mortality was similar for the 2 strategies up to 5 years (hazard ratio [HR], 0.95; 95% CI, 0.85-1.06), as were aorta-related hospitalizations (HR, 1.12; 95% CI, 0.99-1.27), aortic interventions (HR, 1.01; 95% CI, 0.84-1.20), and cardiovascular hospitalizations (HR, 1.05; 95% CI, 0.93-1.20). In a sensitivity analysis that included deaths within the first 30 days, initial TEVAR was associated with lower mortality over a period of 1 year (adjusted HR [aHR], 0.86; 95% CI, 0.75-0.99; P = .03), 2 years (aHR, 0.85; 95% CI, 0.75-0.96; P = .008), and 5 years (aHR, 0.87; 95% CI, 0.80-0.96; P = .004).

Conclusions and Relevance

In this study, 16.0% of patients underwent initial TEVAR within 30 days of uTBAD, and receipt of initial TEVAR was associated with hypertension, peripheral vascular disease, region, Medicaid dual eligibility, and year of admission. Initial TEVAR was not associated with improved mortality or reduced hospitalizations or aortic interventions over a period of 5 years, but in a sensitivity analysis that included deaths within the first 30 days, initial TEVAR was associated with lower mortality. These findings, along with cost-effectiveness and quality of life, should be assessed in a prospective trial in the US population.

Thoracic endovascular aortic repair or best medical therapy for uncomplicated type B aortic dissection? A meta-analysis

INTRODUCTION

The aim of this meta-analysis was to investigate all studies comparing thoracic endovascular aortic repair (TEVAR) and best medical therapy (BMT) for the treatment of uncomplicated type B aortic dissection (TBAD).

EVIDENCE ACQUISITION

PubMed/Medline and Web of Knowledge were searched until September 2014 for relevant studies published in English. Pooled odds ratio (OR) and its corresponding 95% CI were analyzed with Cochrane Review Manager (RevMan v.5.3).

EVIDENCE SYNTHESIS

Our analysis showed that compared with BMT, TEVAR did not significantly affect 30-day (hospital) mortality. A significantly lower 1-year and 2- or 3-year survival rates was observed with TEVAR vs. BMT. Interestingly, a trend just short of statistical significance towards higher 4- or 5-year survival was found with TEVAR treatment (P=0.08). No significant differences were found in false lumen (FL) thrombosis formation with TEVAR vs. BMT treatment. However, a trend toward less incomplete or no FL thrombosis was noted with TEVAR. No significantly impact on the risk of later re-intervention was found with TEVAR vs. BMT.

CONCLUSIONS

TEVAR did not provide obvious early survival advantage for uncomplicated TBAD over BMT, especially in the patients using TEVAR alone. It may remain a treatment option in uncomplicated TBAD patients with high risks for later complications. More randomized, prospective, long-term studies are needed to further clarify whether TEVAR could be a better first-line treatment strategy vs. BMT for uncomplicated TBAD.

Complicated Open Repair of Type B Aortic Dissection in a Patient With Ehlers-Danlos Syndrome Rescued by Endovascular Intervention

Ehlers-Danlos is a connective tissue disorder characterized by hypermobile joints, hyperextensible skin, and increased bleeding tendency. We report a case involving endovascular repair of an intussusception of aortic dissection that occurred in an Ehlers-Danlos patient following surgical repair of an intercostal artery bleed. Given the rarity of Ehlers-Danlos, continued reporting of treatment outcomes is important for refining complication management in this population. Our experience lends support for endovascular rescue of failed aortic repair that may arise in Ehlers-Danlos patients and contributes to the otherwise small body of literature concerning endovascular intervention in this population overall.

A Novel Solution for Distal Dilation of Chronic Dissection After Repair Involving Visceral Branches: The Road Block Strategy

Aim

Notwithstanding that unprecedented endovascular progress has been achieved in recent years, it remains unclear what is the best strategy to preserve the blood perfusion of abdominal visceral arteries and promote positive aortic remodeling in patients with distal dilatation of chronic aortic dissection in abdominal visceral part (CADAV) after aortic repair. The present study developed a Road Block Strategy (RBS) to solve this conundrum.

Methods and Results

This prospective single-center clinical study included patients suffering from symptomatic distal dilatation of CADAV after aortic repair treated with RBS from January 2015 to December 2019 and followed up regularly for at least 2 years. Stent grafts were implanted first to cover distal tears and expand the true lumen. Device embolization was performed to induce proximal and distal segmental false lumen thrombosis (FLT) apart from the level of the ostia of vital branches. Successful RBS was performed in 13 patients. Significant differences were found in maximum true lumen diameter (p < 0.05), blood flow area in false lumen (FL) (p < 0.001), and the ratio of blood lumen to FL area (p < 0.05) between the pre-procedure and the latest follow-up results. No aortic rupture, vital branches occlusion, thoracic and abdominal pain, or death occurred during hospitalization and follow-up.

Conclusions

Our findings suggest that RBS is feasible in treating distal dilatation of chronic aortic dissection after prior proximal repair, inducing false lumen thrombosis, preventing deterioration of aortic dissection, and maintaining the patency of abdominal visceral arteries.

Descending Aorta Diameters as Predictor of Late Adverse Outcomes in Patients with Uncomplicated Type B Aortic Dissection: A Systematic Review and Meta-Analysis

BACKGROUND

A subset of patients with uncomplicated type B aortic dissection (uTBAD) has been shown to possess higher risk of experiencing late adverse outcomes. Therefore, we conducted an analysis to investigate the role of descending aorta diameters, including total descending aorta diameter and false lumen diameter, as predictor of late adverse outcomes in patients with uTBAD.

METHODS

A systematic search was performed through Pubmed, ClinicalKey, ScienceDirect, and Cochrane Library to identify relevant studies. Our primary outcome was the composite late adverse events following their first episode of hospitalization. All meta-analyses were performed using Review Manager version 5.4.

RESULTS

A total of 2,339 (male 68.8%) patients from a total of 15 cohorts were included in our analysis. During follow-up period, there were 655 (27.3%) and 149 (6.3%) cases of late adverse events and mortality, respectively. Patients with higher initial descending aorta diameter were at higher risk of developing late adverse events (RR 2.99 [2.60, 3.44]; P < 0.001) and mortality (RR 3.15 [2.34, 4.25]; P <0.001) throughout follow-up period. Maximum false lumen diameter at the initial presentation seemed to significantly be associated with late adverse events (RR 1.87 [1.46, 2.39]; P <0.001) but not with mortality (RR 2.55 [0.81-8.00; P = 0.11).

CONCLUSION

Descending aorta diameters, particularly maximum initial descending aorta diameter, is a good and helpful predictor of late adverse outcomes in patients with uTBAD.

Is TEVAR really needed for uncomplicated type B aortic dissection?

Thoracic endovascular aortic repair (TEVAR) has quickly become the mainstay of treatment for acute aortic dissection, in particular cases of acute complicated Stanford Type B dissection (co-TBAD). Necessarily, TEVAR carries with it the risk of postoperative complications, including stroke and renal failure. As a result, the management of patients with uncomplicated type B aortic dissection (un-TBAD), which is generally accepted as being less severe, is safely managed via optimal medical therapy (OMT) alone. However, despite OMT, patients with un-TBAD are at substantial risk of severe disease progression requiring delayed intervention. The cost-benefit ratio associated with TEVAR for un-TBAD is therefore of key interest. Howard and colleagues produced a fascinating systematic review and meta-analysis investigating the clinical outcomes of TEVAR for complicated and uncomplicated TBAD. Their data suggest that there is no significant difference in in-hospital mortality or 5-year survival between TEVAR for un-TBAD and co-TBAD, although the 30-day mortality rate appeared to be higher in the co-TBAD cohort. Patients with co-TBAD appeared to also be at a higher risk of postoperative stroke and TEVAR endoleak, while un-TBAD patients were at a higher risk of postoperative renal failure. Further prospective research into these relationships is recommended to fully elucidate the comparative efficacies of TEVAR for un-TBAD and co-TBAD.

Predictors of adverse events in uncomplicated type B aortic dissection: a systematic review with meta-analysis

INTRODUCTION

Thoracic Endovascular Aortic Repair (TEVAR) has been selectively used for uncomplicated acute type B Aortic Dissection (TBAD); however, not all cases will benefit from TEVAR. A search for high risk clinical and radiographic predictors for complications is ongoing. This systematic review and meta-analysis aimed to identify predictors of major adverse events during follow-up of uncomplicated TBAD, in order to identify who might benefit from elective TEVAR.

EVIDENCE ACQUISITION

A systematic review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-analysis (PRISMA) statement.

EVIDENCE SYNTHESIS

16 studies were included in a qualitative synthesis and 10 in the meta-analysis. Several risk factors associated to major adverse events have been described, including (1) aortic diameter ≥40 mm, (2) greater false lumen diameter (>22mm), (3) patent false lumen, (4) primary entry tear > 10mm, and (5) greater number of false lumen vessels origin. Quantitative synthesis identified an aortic diameter ≥40 mm significantly associated with major adverse events (HR=3.56; p<0.00001). Reporting of false lumen status, aortic diameters and growth, and demographic data was not always congruent with the most recent recommendations by Society for Vascular Surgery and Society of Thoracic Surgeons, published in 2020.

CONCLUSIONS

Acute and subacute patients with uncomplicated TBAD presenting with an aortic diameter ≥ 40 mm and solely treated with BMT have an increased hazard of developing major adverse events (HR), making them potential candidates for TEVAR. Remaining risk factors analysed have weaker evidence.

Management of Uncomplicated Type B Aortic Dissection

Acute aortic dissection has an incidence of approximately half that of symptomatic abdominal and thoracic aneurysm of the aorta and more than twice the mortality of population-based controls. While urgent undelayed open surgery is the strategy of choice in proximal dissection, medical management has been the mainstay of treatment for uncomplicated distal or type B aortic dissection, but endovascular intervention is now considered a potential treatment option for all type B dissection due to its success in complicated cases. Endovascular repair can be technically demanding in aortic dissection, and timing of the repair can have a significant influence on anatomical and clinical outcome. Observational reports of feasibility and reasonable safety are flanked by only two randomised trials; the Acute Dissection Stent Grafting or Best Medical Treatment (ADSORB) trial demonstrated improved remodelling in acute dissection and the INvestigation of STEnt grafts in patients with type B Aortic Dissections (INSTEAD) trial showed better long-term survival in patients treated endovascularly in the subacute phase. Meta-analyses and other large clinical studies have demonstrated mixed results. Due to some risks associated endovascular repair and the requirement of specialist aortic care (which is not always available), a pragmatic approach for current management could involve high intensity serial imaging in the acute phase of a type B aortic dissection, thereby identifying complicated cases for early intervention and selection of patients at high risk of disease progression for deferred endovascular management in the subacute phase within 90 days.

Location of Reentry Tears Affects False Lumen Thrombosis in Aortic Dissection Following TEVAR

Purpose: To report a study that assesses the influence of the distance between the distal end of a thoracic stent-graft and the first reentry tear (SG-FRT) on the progression of false lumen (FL) thrombosis in patients who underwent thoracic endovascular aortic repair (TEVAR). Materials and Methods: Three patient-specific geometrical models were reconstructed from postoperative computed tomography scans. Two additional models were created by artificially changing the SG-FRT distance in patients 1 and 2. In all 5 models, computational fluid dynamics simulations coupled with thrombus formation modeling were performed at physiological flow conditions. Predicted FL thrombosis was compared to follow-up scans. Results: There was reduced false lumen flow and low time-averaged wall shear stress (TAWSS) in patients with large SG-FRT distances. Predicted thrombus formation and growth were consistent with follow-up scans for all patients. Reducing the SG-FRT distance by 30 mm in patient 1 increased the flow and time-averaged wall shear stress in the upper abdominal FL, reducing the thrombus volume by 9.6%. Increasing the SG-FRT distance in patient 2 resulted in faster thoracic thrombosis and increased total thrombus volume. Conclusion: The location of reentry tears can influence the progression of FL thrombosis following TEVAR. The more distal the reentry tear in the aorta the more likely it is that FL thrombosis will occur. Hence, the distal landing zone of the stent-graft should be chosen carefully to ensure a sufficient SG-FRT distance.

Thoracic endovascular repair (TEVAR) versus open surgery for blunt traumatic thoracic aortic injury

BACKGROUND

Blunt traumatic thoracic aortic injury (BTAI) is a life-threatening surgical emergency associated with mortality up to 8000 per year, most commonly caused by rapid acceleration/deceleration injury sustained through motor vehicle accident and/or blunt thoracic trauma. BTAI has high pre-hospital mortality following the primary injury, with only 10% to 15% of patients surviving long enough to reach the hospital. Open surgical repair had remained the standard treatment option for BTAI since successfully introduced in 1959. However, with technological advances, thoracic endovascular repair (TEVAR) offers an alternative treatment option for BTAI. TEVAR is a less invasive surgical approach for management of these already critical patients; many reports have described favourable early outcomes.Thoracic endovascular repair may appear to be superior to open repair for treatment of BTAI. However, its long-term results and efficacy remain unknown. No randomised controlled trials (RCTs) have provided evidence to support the superiority of the endovascular approach versus open repair in the treatment of BTAI. This review aims to address this matter. This is an update of a review first published in 2015.

OBJECTIVES

To determine whether use of thoracic endovascular repair (TEVAR) for treatment of blunt traumatic thoracic aortic injury (BTAI) is associated with reduced mortality and morbidity when compared with conventional open surgery.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL and AMED databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 20 August 2018.

SELECTION CRITERIA

We considered all published and unpublished randomised controlled trials (RCTs) comparing TEVAR and open surgery for BTAI.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed all RCTs identified by the Cochrane Vascular Information Specialist.

MAIN RESULTS

We found no RCTs that met the inclusion criteria for this review.

AUTHORS' CONCLUSIONS

We found no RCTs conducted to determine whether use of TEVAR for the treatment of BTAI is associated with reduced mortality and morbidity when compared to conventional open repair. Hence, we are unable to provide any evidence to guide the treatment option for this life-threatening condition. To perform a randomised controlled trial to clarify the optimal management of BTAI would be highly challenging due to the natural history of the condition. Despite the lack of RCT evidence, clinicians are moving forward with endovascular treatment of BTAI on the basis of meta-analyses of cohort studies and large clinical series.

Endovascular management of ruptured abdominal aortic aneurysms and acute aortic dissections

The management of vascular emergencies is dependent on rapid identification and confirmation of the diagnosis with concurrent patient stabilization prior to immediate transfer to the operating suite. A variety of technological advances in diagnostic imaging as well as the advent of minimally invasive endovascular interventions have shifted the contemporary treatment algorithms of such pathologies. This review provides a comprehensive discussion on the current state and future trends in the management of ruptured abdominal aortic aneurysms as well as acute aortic dissections.

Aortic Remodeling After Total Endovascular Aortic Repair With Multilayer Stents: Computational Fluid Dynamics Analysis of Aortic Remodeling Over 3 Years of Follow-up

PURPOSE

To report Multilayer Flow Modulator (MFM) implantation from the sinotubular junction to the distal infrarenal aorta in the treatment of type B aortic dissection (TBAD) and demonstrate aortic remodeling using computational fluid dynamics (CFD) analysis over the course of 3-year follow-up.

CASE REPORT

A hypertensive patient with complicated TBAD required thoracic endovascular aortic repair due to severe thoracic pain associated with rapid progression of the false lumen aneurysm toward the distal aortic arch. Under general anesthesia, 2 aortic multilayer stents were placed over a 0.035-inch stiff guidewire in the compressed true lumen. The aorta was covered with 2 MFM stents between the sinotubular junction and the distal infrarenal aorta. Serial computed tomography scans showed progressive remodeling of the entire dissected aortic wall, with an excellent result at 24 months. Morphological and CFD vascular analysis confirmed the aortic remodeling, with a false lumen index drop from a preoperative 4.04 to 0.01 at 36 months.

CONCLUSION

Endovascular aortic repair with multilayer stents is a promising treatment for complicated TBAD due to the unique ability of these devices to stabilize the entire aortic wall without compromising the flow in the major aortic side branches.

Short term outcome of thoracic endovascular aortic repair in patients with thoracic aortic diseases

AIM AND BACKGROUND

Open surgical repair for thoracic aortic diseases is associated with a high perioperative mortality and morbidity. Most of type B aortic dissections are uncomplicated and are medically treated which carries a high mortality rate. Thoracic endovascular aortic repair is the first-line therapy for isolated aneurysms of the descending aorta and complicated type B aortic dissection. The aim of this study is to test the safety of early thoracic endovascular aortic repair in patients with uncomplicated type B aortic dissection and patients with thoracic aortic aneurysms.

METHODS

A total of 30 patients (24 men and 6 females; mean age 59 ± 8 years) with uncomplicated type B aortic dissection and descending thoracic aortic aneurysm who underwent endovascular aortic repair in National Heart Institute and Cairo University hospitals were followed up. Clinical follow-up data was done at one, three and twelve months thereafter. Clinical follow-up events included death, neurological deficits, symptoms of chronic mal-perfusion syndrome and secondary intervention. Multi-slice computed tomography was performed at three and six months after intervention.

RESULTS

Of the 30 patients, 24 patients had aortic dissection, and 6 patients had an aortic aneurysm. 7 patients underwent hybrid technique and the rest underwent the basic endovascular technique in whom success rate was 100%. Two patients developed type I endoleak, however both improved after short term follow up. The total mortality rate was 10% throughout the follow-up. Both death and endoleak occurred in subacute and chronic cases, while using TEVAR in acute AD and aneurysm showed no side effects. Early thoracic endovascular aortic repair showed better results and less complications.

CONCLUSION

Along with medical treatment, early thoracic endovascular aortic repair in uncomplicated type B aortic dissections and thoracic aortic aneurysms is associated with better outcome.

Conservative management versus endovascular or open surgery in the spectrum of type B aortic dissection

Background

Type B aortic dissection is a life-threatening acute aortic condition often with acute ischemic signs or symptoms. With initial management focusing on alleviating malperfusion and pain, and avoiding propagation of dissection or rupture both systolic blood and pulse pressure should be reduced initially by an aggressive medical approach. In the setting of persistent signs of complications endovascular strategies have replaced open surgery and led to a fourfold increase in early survival and better long-term outcomes.

Methods

An electronic health database search was performed on articles published between January 2006 and July 2017. Publications were included in this review if (I) the index aortic pathology was type B aortic (distal) dissection; (II) when medical management, open surgical replacement or thoracic endovascular aortic repair were among those options; (III) when at least one of all basic outcome criteria such as survival, spinal cord ischemia and cerebrovascular accident was reported; (IV) when ≥15 serial patients were included. A total of 62 studies were eligible and analysed.

Results

Our manuscript has summarized data collected over 12 years on management specific outcomes in the setting of distal aortic dissection and provides an up-to-date interpretation of the published evidence. For complicated cases, treated acutely, the 30-day or in-hospital mortality was 7.3% when managed by endovascular means, whereas the pooled rate for 30-day or in-hospital mortality was 19.0% when subjected to open repair. For acute uncomplicated type B dissection usually treated with blood pressure lowering medications, the pooled 30-day or in-hospital mortality rate was 2.4%. Survival rates at 5 years averaged at 60% (40% mortality). Freedom from any aortic event ranged from 34.0% to 83.9%, underlining an inherent risk of progression and late complications. For chronic complicated type B dissection, the rates of stroke, paraplegia and operative mortality following endovascular repair ranged from 5% to 13%, 2% to 13% and 2 to 13%, respectively, while 5-year survival rates after open repair ranged from 60% to 90%. In chronic uncomplicated type B dissection almost 90% of patients survive initial hospitalization and were subjected to medical management with a 5-year survival of 50-80%. However, up to 20-55% of medically treated patients develop aneurysmal degeneration after 5 years with an unknown risk of rupture.

Conclusions

Currently, the less invasive strategy of endovascular repair (as compared to open surgery) provides improved 30-day or in-hospital survival in the setting of complicated acute type B aortic dissection and may seek broad application. Open surgical aortic reconstruction should be left to experienced aortic centres if endovascular management is not an option.

Contemporary Results of Endovascular Repair of Isolated Abdominal Aortic Dissection with Unibody Bifurcated Stent Grafts

OBJECTIVES

To report the midterm safety and efficacy of the Aegis™-B (Microport, Shanghai, China) unibody bifurcated stent graft for endovascular treatment of isolated abdominal aortic dissection (IAAD).

BACKGROUND

Isolated abdominal aorta dissection (IAAD) is a rare event. Endovascular stent grafts seem to offer an efficient therapeutic approach to treat IAAD. However, the relatively small diameter of the infrarenal aorta and aortic bifurcation remains the main anatomical limitation to endovascular repair.

METHODS

Between 2008 and 2015, we retrospectively evaluated 32 IAAD patients (21 men; mean age 58 ± 18 years), who underwent endovascular repair using Aegis™-B unibody bifurcated stent graft. Narrow proximal landing zone and narrow distal aorta was present in 11 (34.4%) patients and 10 (31.3%) patients, respectively. In the follow-up period, aortic remodeling was observed with computed tomography angiography.

RESULTS

All patients were treated by endovascular means, with a primary technical success rate of 100%. During a mean follow-up period of 30.71 ± 16.36 months (range, 8-56 months), no death, rupture, stent fracture, material failure, or device migration was observed. Complete false lumen thrombosis was observed in all patients at 1 year, and all patients were free from false lumen growth in the follow-up.

CONCLUSIONS

Endovascular treatment of IAAD using the Aegis™-B system appears to be safe and effective. Results from this study suggest this algorithm can provide stable, secure fixation for IAAD patients with narrow proximal landing zone, and distal aorta.

Changes in Geometry and Cardiac Deformation of the Thoracic Aorta after Thoracic Endovascular Aortic Repair

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) has dramatically expanded treatment options for patients with thoracic aortic pathology. The interaction between endografts and the dynamic anatomy of the thoracic aorta is not well characterized for repetitive physiologic stressors and subsequent issues related to long-term durability. Through three-dimensional (3D) modeling we sought to quantify cardiac-induced aortic deformation before and after TEVAR to assess the impact of endografts on dynamic aortic anatomy.

METHODS

Eight patients with acute (n = 4) or chronic (n = 3) type B dissections, or chronic arch aneurysm (n = 1), underwent TEVAR with a single (n = 5) or multiple (n = 3) Gore C-TAG(s). Cardiac-resolved thoracic CT images were acquired pre- and post-TEVAR. 3D models of thoracic aorta and branch vessels were constructed in systole and diastole. Axial length, mean, and peak curvature of the ascending aorta, arch, and stented lumens were computed from the aortic lumen centerline, delineated with branch vessel landmarks. Cardiac-induced deformation was computed from mid-diastole to end-systole.

RESULTS

Pre-TEVAR, there were no significant cardiac-induced changes for aortic axial length or mean curvature. Post-TEVAR, the ascending aorta increased in axial length (2.7 ± 3.1%, P < 0.05) and decreased in mean curvature (0.38 ± 0.05 → 0.36 ± 0.05 cm^-1, P < 0.05) from diastole to systole. From pre- to post-TEVAR, axial length change increased in the ascending aorta (P < 0.02), mean curvature decreased in the arch and stented aorta (P < 0.03), and peak curvature decreased in the stented aorta (P < 0.05).

CONCLUSIONS

TEVAR for a range of indications not only causes direct geometric changes to the stented aorta but also results in dynamic changes to the ascending and stented aorta. In our cohort, endograft placement straightens the stented aorta and mutes cardiac-induced bending due to longitudinal stiffness. This is compensated by greater length and curvature changes from diastole to systole in the ascending aorta, relative to pre-TEVAR.

Feasibility of a proposed randomized trial in patients with uncomplicated descending thoracic aortic dissection: Results of worldwide survey

The trial we propose will be the first multicenter, randomized, trial investigating the role of thoracic endovascular aortic repair (TEVAR) of uncomplicated type B aortic dissection (TBAD) compared to conservative (medical) management. To document the current management approaches for uncomplicated TBAD, we performed an international survey in 130 centers (in US and worldwide), of whom 114 (89%) responded. Sixty-three (54.8%) respondents do not routinely stent uncomplicated TBAD, and 43 (37.4%) perform TEVAR based on various imaging criteria. One hundred and one respondents (88.6%) agreed that equipoise was present. Almost all respondents agreed that demonstrating an improvement in major aortic complication-free survival with TBAD would lead to change in practice. The results of the survey demonstrate that a major randomized trial to determine the optimal management strategy for uncomplicated TBAD is warranted.

Volumetric analysis demonstrates that true and false lumen remodeling persists for 12 months after thoracic endovascular aortic repair

A 62-year-old man underwent an elephant trunk procedure followed by thoracic endovascular aortic repair (TEVAR). Computed tomography angiography-based models were built to quantify volume of the whole aorta and true and false lumens preoperatively, before TEVAR, after TEVAR, and at follow-up at 3, 6, and 12 months. With TEVAR, descending aortic true lumen volume increased by 54%, then increased additionally by 60% during 12 months. The descending aortic false lumen volume regressed continuously for 12 months following TEVAR, with the most rapid rate from 6 to 12 months at 16 cm3/month. TEVAR immediately increased true lumen volume and continued to remodel the true and false lumens throughout the following 12 months.

Thoracic endovascular repair (TEVAR) versus open surgery for blunt traumatic thoracic aortic injury

BACKGROUND

Blunt traumatic thoracic aortic injury (BTAI) is a life-threatening surgical emergency associated with mortality up to 8000 per year, most commonly caused by rapid acceleration/deceleration injury sustained through motor vehicle accident and/or blunt thoracic trauma. BTAI has high pre-hospital mortality following the primary injury, with only 10% to 15% of patients surviving long enough to reach the hospital. Open surgical repair had remained the standard treatment option for BTAI since successfully introduced in 1959. However, with technological advances, thoracic endovascular repair (TEVAR) offers an alternative treatment option for BTAI. TEVAR is a less invasive surgical approach for management of these already critical patients; many reports have described favourable early outcomes.Thoracic endovascular repair may appear to be superior to open repair for treatment of BTAI. However, its long-term results and efficacy remain unknown. No randomised controlled trials (RCTs) have provided evidence to support the superiority of the endovascular approach versus open repair in the treatment of BTAI. This review aims to address this matter.

OBJECTIVES

To determine whether use of TEVAR for treatment of BTAI is associated with reduced mortality and morbidity when compared with conventional open surgery.

SEARCH METHODS

The Cochrane Vascular Trials Search Co-ordinator searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 7) and clinical trials databases for details of ongoing and unpublished studies.

SELECTION CRITERIA

We considered all published and unpublished randomised controlled trials (RCTs) comparing TEVAR and open surgery for BTAI.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed all RCTs identified by the Trials Search Co-ordinator.

MAIN RESULTS

We found no RCTs that met the inclusion criteria for this review.

AUTHORS' CONCLUSIONS

We found no RCTs conducted to determine whether use of TEVAR for the treatment of BTAI is associated with reduced mortality and morbidity when compared to conventional open repair. Hence, we are unable to provide any evidence to guide the treatment option for this life-threatening condition. To perform a randomised controlled trial to clarify the optimal management of BTAI would be highly challenging due to the natural history of the condition. Despite the lack of RCT evidence, clinicians are moving forward with endovascular treatment of BTAI on the basis of meta-analyses and large clinical series.

[Acute aortic diseases. Diagnostic imaging and therapy]

Diagnostic imaging is crucial in the work-up of acute aortic diseases. Current imaging algorithms enable radiologists differentiating the various entities with subsequent clinically relevant treatment options. Within this educational overview we focus on non-traumatic acute aortic disease. Recent developments of cross sectional imaging are summarized. As for acute aortic disease, we discuss dissections, intramural hematoma, penetrating aortic ulcer, and aortitis. Current treatment options are presented.

TEVAR: Endovascular Repair of the Thoracic Aorta

The development of thoracic endovascular aortic repair (TEVAR) has allowed a minimally invasive approach for management of an array of thoracic aortic pathologies. Initially developed specifically for exclusion of thoracic aortic aneurysms, TEVAR is now used as an alternative to open surgery for a variety of disease pathologies due to the lower morbidity of this approach. Advances in endograft technology continue to broaden the applications of this technique.

Aneurysmal degeneration of the thoracoabdominal aorta after medical management of type B aortic dissections

BACKGROUND

Patients with uncomplicated type B aortic dissections who are managed medically are at risk of aortic aneurysmal degeneration over time. However, the effect of improvement in antihypertensive medications and stricter blood pressure control is unknown. The goal of this study was to determine the rate of aneurysmal degeneration in a contemporary cohort of patients with medically treated type B dissection.

METHODS

Included were all patients with acute uncomplicated type B aortic dissection who were initially managed medically between March 1999 and March 2011 and had follow-up axial imaging studies. Maximum aortic growth was calculated by comparing the initial imaging study to the most current scan or imaging obtained just before any aortic-related intervention. An increase of ≥5 mm was the threshold considered as aortic growth. Predictors of aortic aneurysmal degeneration were determined using Cox proportional hazards models.

RESULTS

We identified 200 patients (61% men) with medically managed acute type B dissections receiving multiple imaging studies. Patients were an average age of 63.4 years, and 75.5% had a history of hypertension. Mean follow-up was 5.3 years (range, 0.1-14.7 years). Mean time between the initial and final imaging studies was 3.2 years (range, 0.1-12.9 years). At 5 years, only 51% were free from aortic growth. Fifty-six patients (28%) required operative intervention (50 open, 6 endovascular repair) for aneurysmal degeneration, and the actuarial 5-year freedom from intervention was 76%. After excluding five patients (2.5%) with early rapid degeneration requiring intervention within the first 2 weeks, the mean rate of aortic growth was 12.3 mm/y for the total aortic diameter, 3.8 mm/y for the true lumen diameter, and 8.6 mm/y for the false lumen diameter. Only aortic diameter at index presentation >3.5 cm was a risk factor for future growth (odds ratio, 2.54; 95% confidence interval, 1.34-4.81; P < .01). Complete thrombosis of the false lumen was protective against growth (odds ratio, 0.19; 95% confidence interval, 0.11-0.42; P < .01).

CONCLUSIONS

Although medical management of uncomplicated acute, type B aortic dissections has been the standard of care, at 5 years, a significant number of patients will require operative intervention for aneurysmal degeneration. Further studies of early intervention (eg, thoracic endovascular aortic repair) for type B aortic dissection to prevent late aneurysm formation are needed.

Management of acute aortic dissection

A new appraisal of the management of acute aortic dissection is timely because of recent developments in diagnostic strategies (including biomarkers and imaging), endograft design, and surgical treatment, which have led to a better understanding of the epidemiology, risk factors, and molecular nature of aortic dissection. Although open surgery is the main treatment for proximal aortic repair, use of endovascular management is now established for complicated distal dissection and distal arch repair, and has recently been discussed as a pre-emptive measure to avoid late complications by inducing aortic remodelling.

Indication of endovascular treatment of type B aortic dissection--literature review

Aortic dissection is a cardiovascular event of high mortality if not early diagnosed and properly treated. In Stanford type A aortic dissection, there is the involvement of the ascending aorta, whereas in type B the ascending aorta is not affected. The treatment of type A aortic dissection is mainly surgical. The hospital mortality of type B aortic dissection surgical treatment is approximately 20%, while medical therapy is 10%. However, half the patients who are discharged from hospital after medical treatment, progress to aortic complications in the following years, and the mortality in three to five years may reach 25-50%. In addition, the surgical treatment of aortic complications after medical treatment, has also a significant mortality. This way, the endovascular treatment comes up as an interesting alternative of a less invasive treatment for this disease. They presented a mortality rate lower than 10% with more than 80% success rate of occlusion and thrombosis of the false lumen. The INSTEAD TRIAL, which randomized patients with uncomplicated type B aortic dissection for optimal medical therapy and endovascular treatment in addition to optimal medical therapy, showed that after three years of follow up, patients who underwent endovascular treatment had lower mortality and aorta-related complications. Therefore, there is a current tendency to recommend the endovascular treatment as a standard for the treatment of type B aortic dissection

Stent graft therapy for false lumen aneurysmal degeneration in established type B aortic dissection (FADED) results in differential volumetric remodeling of the thoracic versus abdominal aortic segments

BACKGROUND

Despite optimal medical therapy of type B aortic dissections, false lumen aneurysmal degeneration of these established dissections (FADED) occur over long term (>6 months). The efficacy of thoracic stent grafts (thoracic endovascular aortic repair [TEVAR]) in promoting aortic remodeling when placed at late time points remains controversial and was the focus of this investigation.

METHODS

Utilizing tomographic scans, the volume of 6 distinct aortic compartments were calculated including the stented true lumen and stented false lumen (STL and SFL), below-stent true and false lumens (BSTL and BSFL), and the infrarenal aorta true and false lumens (IRA TL and IRA FL) when applicable. Cross-sectional areas were calculated at 1-cm intervals, collated, and volumetric ratios were derived from preoperative values.

RESULTS

From 2004 to 2011, 21 patients met inclusion criteria. Complete false lumen (FL) thrombosis was achieved in 85.7% of SFL and 26.3% of BSFL. Volumetric analysis demonstrated that 71% of patients had increased STL volume and 71% had decreased SFL. In the below-stent region, 75% of patients had increased true lumen (TL) with 59% concurrently decreased FL volume. The IRA TL volume increased in 85% of patients and the IRA FL also expanded in 75% of this cohort. At the latest time point, overall growth was noted in the infrarenal aortic segment.

CONCLUSIONS

Utilization of TEVAR in patients suffering from FADED can promote TL expansion with concurrent FL regression; however, progressive dilation in the total infrarenal aorta volume may occur and warrants close surveillance.

Five-year results for endovascular repair of acute complicated type B aortic dissection

INTRODUCTION

Despite a current lack of U.S. Food and Drug Administration approval for the indication, thoracic endovascular aortic repair (TEVAR) has replaced open surgical management for acute complicated type B aortic dissection due to promising short- and midterm data. However, long-term results, with a view toward durability and need for secondary procedures, are limited. As such, the objective of the present study is to report long-term outcomes of TEVAR for acute (≤ 2 weeks from symptom onset) complicated type B dissection.

METHODS

Between July 2005 and September 2012, 50 consecutive patients underwent TEVAR for management of acute complicated type B dissection at a single referral institution. Patient records were retrospectively reviewed from a prospectively maintained clinical database.

RESULTS

Indications for intervention included rupture in 10 (20%), malperfusion in 24 (48%), and/or refractory pain/impending rupture in 17 (34%). One patient (2%) had both rupture and malperfusion indications. Ten (20%) patients required one or more adjunctive procedures, in addition to TEVAR, to treat malperfusion syndromes. In-hospital and 30-day rates of death were both 0%; 30-day/in-hospital rates of stroke, permanent paraplegia/paraparesis, and new-onset dialysis were 2% (n = 1), 2% (n = 1), and 4% (n = 2), respectively. Median follow-up was 33.8 months [interquartile range, 12.3-56.6 months]. Overall survival at 5 and 7 years was 84%, with no deaths attributable to aortic pathology. Thirteen (26%) patients required a total of 17 reinterventions over the study period for type I endoleak (n = 5), metachronous aortic pathology (n = 5), persistent false lumen pressurization via distal fenestrations (n = 4), type II endoleak (n = 2), or retrograde acute type A aortic dissection (n = 1). Median time to first reintervention was 4.5 months (range, 0 days-40.3 months). Of the 17 total reinterventions, six (35%) were performed using open techniques and 11 (65%) with endovascular or hybrid methods; there was no difference in survival between patients who did or did not require reintervention.

CONCLUSIONS

This study confirms the excellent short-term outcomes of TEVAR for acute complicated type B dissection and demonstrates the results to be durable and sustained over long-term follow-up. Although aortic reinterventions were required in one-quarter of patients, no aortic-related deaths were observed. These data support the use of TEVAR for acute complicated type B aortic dissection but also highlight the importance of life-long aortic surveillance by an experienced aortic referral center in order to identify and treat complications of the underlying disease process and treatment, as well as new aortic pathologies, as they arise.

Optimal treatment for patients with chronic Stanford type B aortic dissection: endovascularly, surgically or both?

OBJECTIVES

Patients with chronic Stanford type B aortic dissections (TBAD) are traditionally treated medically, but some of the affected thoracic and thoracoabdominal aortic segments progress to large aneurysms with a significant risk of rupture. The purpose of this study is to retrospectively evaluate, with an 'all-comers' approach, the survival and the outcome of patients following thoracic endovascular aortic repair (TEVAR) or conventional open surgery for chronic TBAD as a first-line therapy or a secondary option after failed medical treatment.

METHODS

Between January 2000 and May 2010, 80 consecutive patients (59 males, median age 63, inter-quartile range (IQR) 55-69) suffering from chronic TBAD were treated at our institution. Thirty-three were treated medically (Group A, median age: 65, IQR: 58.5-71.5), 32 received TEVAR (Group B, median age: 62, IQR: 54-67.5) and 15 patients underwent conventional open surgery (Group C, median age: 61, IQR: 54-66). The median follow-up was 42 months (range: 0.1-124.7) and 100% complete.

RESULTS

There were no significant differences with regard to age, gender and associated comorbidities between the treatment groups. The overall hospital mortality for chronic TBAD was 6.3% (n = 5); in-hospital mortalities for Groups A, B and C were 3.0, 6.2 and 13.4%, respectively. The incidence of major complications, such as paraplegia, malperfusion, renal failure and cardiac arrhythmia, did not significantly differ between the three groups. Postoperative stroke occurred more often after conventional open surgery (Group C: 13.3%; P = 0.07). Reintervention for TBAD pathology was required in Groups A, B and C in 12.1, 28.1 and 0%, respectively (P = 0.03). Secondary open surgery post-TEVAR was required in 7 cases (21.8%) with no postoperative paraplegia.

CONCLUSIONS

Open surgery for extensive thoracic and thoracoabdominal repair in chronic TBAD may be performed with acceptable early and mid-term outcomes. TEVAR for aortic complications in patients with chronic dissection may be successfully performed as a first-stage procedure in order to stabilize the patient and serve as a 'bridge' to secondary open surgery. However, close surveillance is mandatory for the timely detection of aneurysm enlargement, malperfusion or impending rupture after TEVAR.

Early malperfusion, ischemia reperfusion injury, and respiratory failure in acute complicated type B aortic dissection after thoracic endovascular repair

BACKGROUND

The aim of this study was to determine the early mortality and major complications of acute complicated type B aortic dissection (ACBD) after thoracic endovascular aortic repair (TEVAR).

METHODS

Twenty-six consecutive patients with ACBD who underwent TEVAR were included. Clinical indications before TEVAR and in-hospital mortality and major complications after TEVAR were analyzed and compared with similar reports.

RESULTS

TEVAR was technically successful in all cases. In-hospital mortality occurred in four patients (15%), and major complications occurred in an additional four patients (15%). Three of the four (75%) of the deaths were associated with malperfusion and ischemia reperfusion injury (IRI), and 3/4 (75%) of the major complications were caused by respiratory failure (RF).

CONCLUSIONS

In-hospital mortality associated strongly with severe end-organ malperfusion and IRI, while major complications associated with RF, during TEVAR. Our results indicate that malperfusion, IRI and respiratory failure during TEVAR should be carefully monitored and aggressively treated.

Endovascular versus conventional medical treatment for uncomplicated chronic type B aortic dissection

BACKGROUND

Aortic dissection is a potentially life-threatening condition that occurs when a tear forms in the inner lining of the aorta. It has traditionally been treated by blood pressure control (medical treatment) or open surgery, both with high mortality rates. More recently stent-graft repair has been suggested as an alternative.

OBJECTIVES

To identify the best management for uncomplicated (without rupture of the organs or malperfusion of the extremities) subacute or chronic type B aortic dissection.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched their Specialised Register (last searched May 2012) and CENTRAL (2012, Issue 4). Clinical trials databases were searched for ongoing or unpublished studies.

SELECTION CRITERIA

All randomised controlled trials designed to compare the outcome of uncomplicated (without rupture of the organs or malperfusion of the extremities) chronic (occurring more than two weeks previously) type B aortic dissection when treated by stenting adjunctive to best medical treatment versus best medical treatment alone were included.

DATA COLLECTION AND ANALYSIS

Data on all cause and aorta-related mortality at two years was collected and analysed. In addition, secondary outcome measures were analysed, including morbidity, complications (additional endovascular or open surgery for rupture, expansion or malperfusion) and quality of life.

MAIN RESULTS

A single trial was identified that fulfilled the inclusion criteria (INSTEAD trial). The two-year all cause survival was not statistically significantly different between study groups (95.6% ± 2.5% in the optimised medical therapy (OMT) group and 88.9% ± 3.7% in the thoracic endovascular aneurysm repair (TEVAR) + OMT group; log rank test P = 0.15).

AUTHORS' CONCLUSIONS

Overall, the data at two years were insufficient to make any practice recommendations. However, the data on the anatomic remodeling of dissected aortas observed after TEVAR + OMT is encouraging and future studies should follow up cases for at least five years to see if early endovascular interventions, even in stable initially uncomplicated type B patients, are of long-term benefit.