Aortic Morphology Following Endovascular Repair of Acute and Chronic Type B Aortic Dissection: Implications for Management

Endovascular Treatment Options for Chronic Dissections

Aortic dissections are classified based on the location of the entry tear. A major concern in chronic aortic dissections is aneurysmal degeneration. Aneurysmal degeneration can lead to aortic expansion and potentially death. False lumen patency is a predictor of outcomes in type B aortic dissections. Thoracic endovascular aortic repair (TEVAR) can be used to treat chronic aortic dissections. TEVAR aims to occlude the false lumen to promote thrombosis and favorable aortic remodeling. However, its benefit may be limited in chronic dissection. Several techniques have been developed to treat chronic dissections with TEVAR.

STABILISE technique to promote aortic remodeling in acute/subacute type B dissection

The goals of treating type B aortic dissections include maintaining or restoring blood supply in cases of organ malperfusion, preventing aortic rupture, promoting aortic remodeling, and preventing disease progression and aneurysmal degeneration. The European Society of Vascular and Endovascular Surgery guidelines recommend endovascular treatment for patients with complicated acute/subacute type B aortic dissections and those failing medical management. Several techniques have been used over the past few decades. Recently, the STABILISE (Stent-Assisted Balloon-Induced Intimal Disruption and Relamination in Aortic Dissection Repair) technique has been proposed to treat type B aortic dissections. This method involves proximal thoracic aortic stent grafting with the deployment of distal bare stents, followed by ballooning to intentionally rupture the intimal lamella, allowing the true lumen to fully expand and resulting in a "single-channeled aorta." Since its adoption, several authors have reported satisfactory results, demonstrating that the technique is safe and effective, and it could be considered a serious attempt to promote positive aortic remodeling over time. This paper provides an analysis of presurgical preparation and planning, detailed procedural description during surgery, necessary support equipment, and strategies for perioperative management.

Questions and Certainty in Diagnosis and Management of Acute Type B Aortic Dissection

Type B aortic dissection (TBAD) is a severe cardiovascular condition that requires timely diagnosis and intervention to prevent life-threatening complications. The aim of this review was to focus on the most crucial and controversial aspects of contemporary TBAD management. It is recognized that in the acute phase, computed tomography angiography (CTA) plays an essential role in evaluating the extent of the dissection and monitoring disease progression. CTA has significantly improved the management of TBAD by providing detailed assessments of aortic anatomy and dynamic flow changes, positioning it as the cornerstone imaging modality for identifying acute high-risk patients who may require early intervention. Recently, new advances in magnetic resonance imaging (MRI) and positron emission tomography (PET) technology have the potential to provide further information beyond imaging alone. However, such sophisticated techniques should be reserved for stable patients after the acute phase. After decades of medical therapy and high risk surgery, thoracic endovascular aortic repair (TEVAR) has emerged as a minimally invasive alternative to open surgery for complicated TBAD, offering lower perioperative morbidity and mortality. Nevertheless, its use in uncomplicated TBAD remains a topic of ongoing debate. While recent studies suggest that preemptive TEVAR combined with optimal medical therapy may reduce late adverse events and improve long-term outcomes, these findings remain controversial. This review critically analyzes the current literature on both diagnosis and TEVAR treatment, evaluating these controversies in the context of clinical practice.

Simulation of thoracic endovascular aortic repair in a perfused patient-specific model of type B aortic dissection

PURPOSE

Complicated type B Aortic dissection is a severe aortic pathology that requires treatment through thoracic endovascular aortic repair (TEVAR). During TEVAR a stentgraft is deployed in the aortic lumen in order to restore blood flow. Due to the complicated pathology including an entry, a resulting dissection wall with potentially several re-entries, replicating this structure artificially has proven to be challenging thus far.

METHODS

We developed a 3d printed, patient-specific and perfused aortic dissection phantom with a flexible dissection flap and all major branching vessels. The model was segmented from CTA images and fabricated out of a flexible material to mimic aortic wall tissue. It was placed in a pulsatile hemodynamic flow loop. Hemodynamics were investigated through pressure and flow measurements and doppler ultrasound imaging. Surgeons performed a TEVAR intervention including stentgraft deployment under fluoroscopic guidance.

RESULTS

The flexible aortic dissection phantom was successfully incorporated in the hemodynamic flow loop, a systolic pressure of 112 mmHg and physiological flow of 4.05 L per minute was reached. Flow velocities were higher in true lumen with a up to 35.7 cm/s compared to the false lumen with a maximum of 13.3 cm/s, chaotic flow patterns were observed on main entry and reentry sights. A TEVAR procedure was successfully performed under fluoroscopy. The position of the stentgraft was confirmed using CTA imaging.

CONCLUSIONS

This perfused in-vitro phantom allows for detailed investigation of the complex inner hemodynamics of aortic dissections on a patient-specific level and enables the simulation of TEVAR procedures in a real endovascular operating environment. Therefore, it could provide a dynamic platform for future surgical training and research.

Successful factors for improving aortic remodeling with thoracic endovascular repair and bare stent extension

OBJECTIVE

Proximal ExTension to Induce COmplete ATtachment (PETTICOAT), which uses downstream bare metal stents for structural support, demonstrates potential, yet its adoption is limited by variable outcomes. This study elucidates the potential of PETTICOAT in aortic dissection, emphasizing the determinants that guide patient selection.

METHODS

A retrospective analysis of 60 patients who underwent full PETTICOAT for aortic dissections was conducted. A multivariate logistic regression model identified predictors of favorable aortic remodeling. Patients underwent standardized follow-up with computed tomography scans to assess size, volumetric changes, and anatomical conditions. Selection criteria included full PETTICOAT application and a minimum of 3 months of follow-up. Demographics, preoperative conditions, and procedural details were collected and analyzed.

RESULTS

The analysis identified predictors of favorable aortic remodeling, including age >60 years, a larger downstream aorta stent graft, a smaller abdominal aorta (<450 mm2), and oral angiotensin II receptor blocker administration. Over a median 47.5 months of follow-up, survival rates in the favorable remodeling (97.3%) and unfavorable groups (100%) were similar. Downstream aortic event-free survival rates did not differ significantly (89.2% vs 73.9%), although the unfavorable group had a relatively higher incidence of distal stent-induced new entries (26.1% vs 8.1%).

CONCLUSIONS

The PETTICOAT concept effectively enhances aortic remodeling in complex aortic dissections. Predictors for favorable remodeling, including age, stent graft sizing, aortic diameter, and angiotensin II receptor blocker therapy, offer insights for optimizing patient selection. This approach improves survival outcomes, mitigates risks associated with untreated aortic segments, and provides a minimally invasive solution for aortic dissections. Despite some outcome variations, the technique holds promise for addressing the challenges of aortic dissections, with the potential for further refinement in patient selection and technique application.

Outcomes of patients with acute complicated type B aortic dissections repaired with the Zenith dissection endovascular system compared to aortic stent graft

OBJECTIVES

We aim to evaluate the safety and effectiveness of the Zenith Dissection Endovascular System (ZDES; Zenith TX2 Dissection Endovascular Graft with Pro-Form and Zenith Dissection Endovascular Stent), which uses a proximal stent graft along with a distal bare metal stent compared to traditional stent grafts in the repair of acute, complicated Type B Aortic Dissection (AcTBAD).

METHODS

This retrospective study reviews the medical charts of 32 patients with AcTBAD repaired at a single urban academic medical center. 16 of these AcTBAD cases were repaired with the ZDES (87.5% male; mean age, 63.1 years), and 16 were repaired with stent grafts (62.5% male; mean age, 60.6 years). Outcomes include 30-day morbidity, false lumen thrombosis and aneurysmal degeneration at 6 months and 1 year, thirty-day and three-year mortality, and freedom from secondary surgical intervention.

RESULTS

Twelve total postoperative adverse events occurred in the ZDES group compared to 37 in the stent graft group (p = .046). The notable adverse events included renal insufficiency (p = .04) and refractory pain (p = .002). At the 6-month follow-up, complete or partial false lumen thrombosis was noted in 100% of patients (16/16) in the ZDES group and 56.3% of patients (9/16) in the stent graft group (p < .01). At the 12-month follow-up, complete or partial thrombosis of the false lumen was noted in 1 additional patient in the stent graft group for a total of 62.6% of patients (10/16; p = .018). Growth (>5 mm) of the maximum transaortic diameter at 12 months was noted in 33.3% of patients (5/15) in the ZDES group and 54% of patients (7/13) in the stent graft group (p = .45). Thirty-day mortality occurred in one patient in the ZDES group and no patients in the stent graft group (p = 1.0). Three-year mortality occurred in four patients in the stent graft group and no patients in the ZDES group (p = .11). Although more patients in the ZDES group underwent secondary intervention to address aortic growth, there were no differences between the two groups in freedom from any secondary intervention at 365 days post-procedure (p = .13).

CONCLUSIONS

Patients treated with ZDES had fewer post-procedural adverse events. Although the use of the ZDES had favorable false lumen thrombosis at 6 and 12 months, the device was not associated with a statistically significant change in transaortic diameter. Our single institution study demonstrated that ZDES has favorable clinical outcomes, but further investigation is needed to better understand aortic remodeling in the distally stented regions. Additionally, further research is necessary to explore the incidence of endoleaks associated with ZDES to optimize long-term patient outcomes.

Emerging Trends in the Care of Type B Aortic Dissections

Aortic dissection is the most common of the acute aortic syndromes. Acute aortic dissection remains a highly morbid and potentially lethal condition despite contemporary advances in medical and surgical care. Type B aortic dissection (TBAD) is classified as uncomplicated, uncomplicated with high-risk features, and complicated. The role of thoracic endovascular aortic repair (TEVAR) in uncomplicated TBAD remains uncertain and is the topic of ongoing clinical trials. In most complicated cases, TEVAR is effective at restoring visceral and extremity blood flow. TEVAR has also been shown to arrest hemorrhage in the setting of thoracic aortic rupture. TEVAR has been demonstrated to induce satisfactory remodeling in the covered segment of the thoracic aorta, but progressive enlargement of the visceral aorta has led to a variety of techniques designed to promote remodeling in the uncovered aortic segment. There is a need to better define high-risk features so that treatment can be tailored to specific clinical conditions.

Mid-term Outcomes of Thoracic Endovascular Aortic Repair (TEVAR) in Acute Complicated Type B Aortic Dissection: A Comprehensive Analysis of Aortic Remodeling Patterns

Purpose

This study provides a comprehensive analysis of the clinical outcomes associated with endovascular treatment for acute complicated type B aortic dissection, with a focus on the complex process of aortic remodeling.

Materials and Methods

We conducted a retrospective investigation using data extracted from the Songklanagarind Hospital database between January 2010 and January 2022. Electronic medical records of patients who underwent thoracic endovascular aortic repair (TEVAR) for acute complicated type B aortic dissections were reviewed. The analysis focused on in-hospital outcomes, overall survival, aorta-related survival, reintervention-free survival, and changes in aortic lumen diameter to assess aortic remodeling.

Results

Over the study period, 32 patients with acute complicated type B aortic dissections underwent TEVAR. The in-hospital mortality rate was 9.4%, with complications occurring in 21.9% of patients. Temporary acute kidney injury was observed in 9.4% of the cases, wound bleeding in 6.3%, pneumonia in 6.3%, and permanent spinal cord ischemia in 3.1%. Re-intervention was necessary in 6.3% of cases. The overall survival rates at 6 months, 1 year, 3 years, and 6 years were 78%, 75%, 65%, and 44%, respectively. Aorta-related survival rates were 87%, 87%, 83%, and 75% at the corresponding time intervals. The reintervention-free survival rates were 96%, 96%, 71%, and 71%, respectively. Survival analysis revealed that patients with ideal aortic remodeling experienced the most favorable outcomes, whereas those with undesirable aortic remodeling exhibited the least favorable survival. Notably, undesirable pattern of aortic remodeling emerged as a singular factor with a statistically significant influence on predicting survival (hazard ratio 4.37, P-value=0.021).

Conclusion

TEVAR resulted in favorable aorta-related survival outcomes. Notably, the identification of changes in aortic lumen diameter alongside false lumen thrombosis, encapsulated within the framework of aortic remodeling patterns, has emerged as a robust predictor of post-TEVAR survival outcomes.

Long-term outcomes of primary surgical repair for communicating DeBakey IIIb chronic dissecting aortic aneurysm

Objective

This study aimed to evaluate the long-term outcomes of surgical strategies for communicating DeBakey IIIb chronic dissecting aortic aneurysm, considering the optimal primary surgical repair to prevent aortic events.

Methods

From 2002 to 2021, 101 patients with communicating DeBakey IIIb chronic dissecting aortic aneurysm who underwent surgical repair were categorized based on the primary surgical repair: 1-stage repair of thoracoabdominal aortic aneurysm (TAAAR) (n = 22) or staged repair, such as descending thoracic aneurysm repair (DTAR) (n = 43) or total arch replacement with elephant trunk implantation (TARET) (n = 25), and thoracic endovascular aortic repair (TEVAR) (n = 11). Early and late postoperative outcomes were compared among the groups.

Results

Early outcomes for TAAAR, DTAR, TARET, and TEVAR were associated with the incidence of stroke (9.1% vs 0% vs 4.0% vs 9.1%, respectively), spinal cord injury (13.6% vs 4.7% vs 8.0% vs 0%, respectively), and in-hospital mortality (9.1% vs 2.3% vs 0% vs 9.1%, respectively). During follow-up, the 10-year overall survival and 7-year aortic event-free rates for TAAAR, DTAR, TARET, and TEVAR were 61.8%, 71.6%, 21.5%, and 26.5% and 93.8%, 84.3%, 74.4%, and 51.4%, respectively. TAAAR had significantly higher overall survival (P = .05) and aortic event-free rates (P = .03) than TEVAR. TARET (hazard ratio, 2.27; P < .01) and TEVAR (hazard ratio, 3.40; P < .01) were independently associated with the incidence of aortic events during follow-up.

Conclusions

Considering the optimal primary surgical repair based on long-term outcomes, TEVAR was not a durable treatment option. Patient-specific TAAAR or DTAR should be considered rather than defaulting to minimally invasive primary repairs for all patients with communicating DeBakey IIIb chronic dissecting aortic aneurysm.

Preemptive treatment in the acute and early subacute phase of uncomplicated type B aortic dissections with poor prognosis factors

Objective

Due to its favorable outcome regarding late morbidity and mortality, thoracic endovascular repair (TEVAR) is becoming more popular for uncomplicated type B aortic dissection (TBAD). This study aimed to compare preemptive endovascular treatment and optimal medical treatment (OMT) and OMT alone in patients presenting uncomplicated TBAD with predictors of aortic progression.

Design

Retrospective multicenter study.

Methods

We analyzed patients with uncomplicated TBAD and risk factors of progression in two French academic centers. Aortic events [defined as aortic-related (re)intervention or aortic-related death after initial hospitalization], postoperative complications, non-aortic events, and radiologic aortic progression and remodeling were recorded and analyzed. Analysis was performed on an intention-to-treat basis.

Results

Between 2011 and 2021, preemptive endovascular procedures at the acute and early subacute phase (<30 days) were performed on 24 patients (group 1) and OMT alone on 26 patients (group 2). With a mean follow-up of 38.08 ± 24.53 months, aortic events occurred in 20.83% of patients from group 1 and 61.54% of patients from group 2 (p < .001). No patient presented aortic-related death during follow-up. There were no differences in postoperative events (p = 1.00) and non-aortic events (p = 1.00). OMT patients had significantly more aneurysmal progression of the thoracic aorta (p < .001) and maximal aortic diameter (p < .001). Aortic remodeling was found in 91.67% of patients in group 1 and 42.31% of patients in group 2 (p < .001). A subgroup analysis of patients in group 1 showed that patients treated with preemptive TEVAR and STABILISE had reduced maximum aortic diameters at the 1-year (p = .010) and last follow-up (p = .030) compared to those in patients treated with preemptive TEVAR alone.

Conclusion

Preemptive treatment of uncomplicated TBAD with risk factors of progression reduces the risk of long-term aortic events. Over 60% of medically treated patients will require intervention during follow-up, with no benefit in terms of postoperative events. Even after surgical treatment, patients in the OMT group had significantly more aneurysmal progression, along with poorer aortic remodeling.

STABILISE (Stent-Assisted Balloon-Induced Intimal Disruption and Relamination in Aortic Dissection Repair) Is Associated With Good Anatomical Results on the Distal Thoracoabdominal Aorta at 2 Years

PURPOSE

The aim of this comparative study was to evaluate the increased aortic diameter of the distal aorta after implementing the STABILISE technique in complicated type B aortic dissection (AD).

DESIGN

This is a comparative monocentric retrospective study.

MATERIALS AND METHODS

All patients who underwent an STABILISE procedure for complicated AD between 2018 and 2020 were included and compared with a historic cohort treated with thoracic endovascular aortic repair (TEVAR) alone. Aortic diameters were measured at 6 different levels on the thoracic and abdominal aorta. The primary end point was an increased aortic diameter at 1 and 2 years. The exclusion criterion was the absence of a computed tomography (CT) scan at 1 or 2 years.

RESULTS

A total of 55 patients were included: 24 in the TEVAR group and 31 in the STABILISE group. At the level of the stent graft, there was a decrease in aortic diameters in both groups without significant differences. At the level of the distal aorta, there was an increase in aortic diameters in both groups without significant differences. There were significantly more patients in the TEVAR group with an unfavorable increase in aortic diameter >5 mm of the distal aorta at 2 years than in the STABILISE group: 8 (33%) vs 1 (3%) (p=0.01). For chronic ADs, a significantly greater increase in aortic diameters of the distal aorta was observed in the STABILISE group.

CONCLUSIONS

The STABILISE technique is technically feasible and potentially leads to decreased longer re-intervention rates; indeed, more patients had an unfavorable increase in aortic diameter in the TEVAR group than in the STABILISE group at 2 years. The high rate of long-term distal aortic aneurysm progression and reintervention after TEVAR alone suggests that this option is not sufficient to definitively treat these complex patients.

CLINICAL IMPACT

This article reported the results of stent assisted balloon induced intimal disruption and relamination (STABILISE) with a follow-up at 2 years. This is the first comparative study between STABILISE, which has emerged as a new technique inducing aortic remodeling and therefore better long-term outcome, and the standard technique TEVAR alone. STABILISE technique is associated with good results on the distal aorta at 2 years with a rate of patient with unfavorable aortic diameter evolution greater in TEVAR group compared to STABILISE group and could improve the long-term results on the distal aorta by inducing extensive aortic remodeling.

Risk Factors for Incomplete Aortic Remodeling With Stent-Assisted Balloon-Induced Intimal Disruption and Relamination in Aortic Dissection Repair for Complicated Aortic Dissection: Results of a Multicenter Study

PURPOSE

The STABILISE technique has extended the treatment of aortic dissection to the thoracoabdominal aorta to achieve complete aortic remodeling. The aim of this multicenter study was to analyze the short- and midterm anatomical results of the STABILISE technique.

MATERIALS AND METHODS

We retrospectively analyzed patients treated with the STABILISE technique for complicated aortic dissection at 3 French academic centers. The aortic diameter at different levels was measured preoperatively, postoperatively, and at 1 year.

RESULTS

Between 2018 and 2020, 58 patients, including 47 men (average patient age: 60±11 years), were treated for type B aortic dissection in 34 cases and residual aortic dissection after type A repair in 24 cases. Three (5.2%) patients died postoperatively. Complete aortic remodeling (false lumen thrombosis and complete reapposition of the intimal flap) was achieved in 45/55 patients (81.8%), and false lumen thrombosis in the thoracic aorta was achieved in 52/55 patients (94.5%). At 1 year, with a computed tomographic (CT) scan available for 98.2% (54/55) of patients, we observed a significant decrease in the maximal thoracic aortic diameter and a significant increase in the aortic diameter at the bare-stent level compared with the preoperative CT scan. Severe aortic angulation (p=0.024) was a risk factor for incomplete aortic remodeling and significantly increased the aortic diameter (p=0.032). Chronic aortic dissection was associated with an increased risk of incomplete aortic remodeling (p=0.002).

CONCLUSIONS

STABILISE for complicated aortic dissection results in false lumen thrombosis, complete reapposition of the intimal flap, and a decrease in the maximum aortic diameter in most cases. Incomplete reapposition of the intimal flap, which is more frequent in cases of chronic aortic dissection and severe aortic angulation, is a risk factor for a significant increase in the aortic diameter at the bare-stent level, and this risk justifies close follow-up and better patient selection.

CLINICAL IMPACT

STABILISE technique for complicated aortic dissection results in false lumen thrombosis, complete aortic remodeling and a decrease in the maximum aortic diameter in most cases. At the bare-stent level, incomplete reapposition of the intimal flap, more frequent in chronic aortic dissection and severe aortic angulation, is a risk factor for an increased aortic diameter. This finding justifies close follow-up and better patient selection; thus, the STABILISE technique should be used with care in chronic aortic dissection and severe aortic angulation.

Aortic Remodeling After Thoracic Endovascular Aortic Repair for Nonacute Uncomplicated Type B Aortic Dissection

BACKGROUND

Entry closure with thoracic endovascular aortic repair (TEVAR) for Stanford type B aortic dissection (TBAD) results in aortic remodeling recently. This study aimed to evaluate the relationship between aortic diameter or timing of surgical intervention from onset and remodeling after TEVAR for uncomplicated nonacute TBAD.

METHODS

Between April 2014 and December 2021, 83 consecutive patients underwent TEVAR for TBAD at our center. Forty patients with subacute and chronic uncomplicated TBADs with a patent false lumen, who could be followed up for at least 6 months, were included in this study. Indications for TEVAR included aortic diameter enlargement and preemptive treatment to prevent future aneurysmal changes in patients at risk of aortic diameter enlargement. Aortic remodeling was accessed, and data between the remodeling and nonremodeling groups were compared.

RESULTS

The technical success rate was 97.5%, with a type Ia endoleak remaining in 1 patient. No operative or in-hospital mortality occurred. Paraparesis occurred in only 1 patient (2.5%). Follow-up was completed at a median of 53.5 months. Late death occurred in 3 cases, but there were no aortic-related deaths. Late aortic remodeling was achieved in 22 patients (55%). The preoperative maximum aortic diameter (PMAD) in the thoracic aortic region was 51.5 mm in the nonremodeling group, significantly larger than 42.5 mm in the remodeling group (P < 0.0001). The cutoff value of the PMAD for predicting aortic remodeling was 45 mm (area under the curve, 0.917; P = 0.028). The remodeling group had an earlier time from onset to intervention than the nonremodeling group, with a cutoff value of 6.3 months (area under the curve, 0.743; P = 0.021).

CONCLUSIONS

TEVAR for nonacute uncomplicated TBAD resulted in a late aortic remodeling rate of 55%. This study suggested that a PMAD of >45 mm or a period >6.3 months between dissection onset and surgery hinders aortic remodeling after TEVAR.

Prevention of distal stent graft-induced new entry after endovascular repair for type B aortic dissection: A retrospective cohort study

OBJECTIVES

Distal stent graft-induced new entry (dSINE) can occur after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD). In this study we aimed to compare the effectiveness of restrictive bare stent (RBS), tapered stent graft (TSG), and non-TSG in TEVAR in preventing dSINE after a midterm follow-up.

METHODS

This retrospective cohort study included patients with TBAD who underwent TEVAR (June 2010 to December 2018). The occurrence of dSINE during follow-up was examined. Predictors of dSINE were determined using Fine-Gray regression with death as the competing event. Survival was evaluated using Cox proportional hazards regression.

RESULTS

Finally, 364 patients were included: 111 with non-TSG TEVAR, 125 with TSG TEVAR, and 128 with TEVAR with RBS. After 54.5 months, incidences of dSINE in the 3 groups were 12.61%, 4.80%, and 1.56%, respectively (P = .002). On Fine-Gray regression adjusted for clinically relevant covariates, the expansion mismatch ratio (subdistribution hazard ratio, 1.09; 95% CI, 1.07-1.12; P < .001) and complete false lumen thrombosis (subdistribution hazard ratio, 0.35; 95% CI, 0.13-0.94; P = .037) were identified as predictors of dSINE. The Cox proportional hazards regression analysis revealed that dSINE was not only a risk factor for aortic-related mortality (hazard ratio, 17.90; 95% CI, 3.27-98.12; P = .001), but also a predominant risk factor for all-cause mortality (hazard ratio, 4.91; 95% CI, 1.66-14.52; P = .004).

CONCLUSIONS

dSINE can happen in TBAD patients who undergo TEVAR. Thus, long-term surveillance is crucial. TSG and RBS had lower expansion mismatch ratios, which might help prevent dSINE.

Self-occluding Candy-Plug: Implantation Technique to Obtain False Lumen Thrombosis in Chronic Aortic Dissections

PURPOSE

To describe the implantation steps of the latest generation of candy-plug device (third CP generation [CP III]) and to illustrate its possible pitfalls by discussing a case in whom this device was employed to occlude the false lumen (FL) of a chronic type B aortic dissection.

TECHNIQUE

A 69 year-old male patient who underwent a frozen elephant trunk arch repair due to residual type A aortic dissection developed a FL aneurysmal degeneration limited to the descending thoracic aorta. Two thoracic stent-grafts were deployed into the true lumen up to the celiac trunk origin. Then, the FL was occluded with a self-occluding CP III device (Cook Medical, Bloomington, Indiana), placed at the same level as the distal thoracic stent-graft. The distal un-stented sleeve was pushed upward to allow immediate occlusion of its central lumen, avoiding interference with reno-visceral arteries arising from the FL. Both intraoperative transesophageal echocardiography and follow-up computed tomographic angiography scan demonstrated complete FL thrombosis.

CONCLUSION

The introduction of CP III with its self-occluding mechanism helped to shorten and standardize the procedure. However, adjunctive steps may be needed to immediately obtain FL occlusion and avoid hampering the perfusion of vessels arising from the FL.

Evaluation of false lumen occluders implanted in the abdominal aorta false lumen

OBJECTIVE

Management of postdissection thoracoabdominal aneurysms with a fenestrated and/or branched endograft (F/BEVAR) is associated with favorable outcomes. Treatment should include both true lumen endografting and false lumen occlusion (FLO). Favorable results have recently been reported for FLO in the false lumen of the thoracic aorta. The purpose of this study is to analyze the results of FLO of the abdominal aorta in patients treated for post dissection thoracoabdominal aneurysm.

METHODS

A multicenter retrospective analysis of prospective data of consecutive patients managed for post dissection thoracoabdominal aortic aneurysm from April 2019 to December 2022 with F/BEVAR associated with FLO in the abdominal false lumen was conducted. The STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) was followed. Baseline demographics, operative details, and early outcomes (mortality, length of stay) were recorded. Primary endpoints were technical and clinical success. FLO technical success was defined as complete occlusion of false lumen backflow above the FLO on completion angiogram.

RESULTS

During the 3-year study, 23 patients were treated for post dissection thoracoabdominal aneurysm with F/BEVAR and the use of abdominal FLO. Twenty-one patients (91.3%) had received prior endovascular treatment. The technical and clinical success was 95.7%. The abdominal FLO had a technical success rate of 78.3%. The median diameter of the FLO was 34 mm. No patient died during the perioperative period, and one patient had spinal cord ischemia (4.3%) with partial recovery. Six patients (26.1%) required early reintervention. The median duration of hospitalization in the intensive care unit and overall was 1 day (interquartile range, 0-3 days) and 7.5 days (interquartile range, 2-22 days), respectively. During the mean follow-up of 9.9 ± 9.0 months, no patient died. False lumen occlusion was complete or partial in nine (39.1%) and nine (39.1%) patients, respectively. No aortic rupture occurred during follow-up. Maximum aortic diameter decreased in 48% and remained stable in 39% of cases.

CONCLUSIONS

Abdominal aorta FLO during endovascular treatment of post dissection thoracic abdominal aortic aneurysm is associated with favorable outcomes. It offers an additional staging therapeutic option before extensive aorto-bi-iliac coverage, associated with low spinal cord ischemia rates. FLO also provides high rates of false lumen occlusion and false lumen remodeling during follow-up. Longer follow-up and larger cohorts are required to confirm these very promising early findings.

Sizing the Frozen Elephant Trunk Based on Aortic Pathology and the Importance of Pre-Operative Imaging

The frozen elephant trunk is a formidable tool for the aortovascular surgeon. An appreciation of how to size the graft in different pathologies is key in achieving optimal results. Herein, we demonstrate worked examples of how imaging can be used to plan for a frozen elephant trunk and discuss the nuisances and uncertainties of sizing using three index cases: Type A aortic dissection, distal thoracic aortic aneurysm and chronic dissection.

Clinical Outcomes and Factors Associated With Aortic Shrinkage After Thoracic Endovascular Aortic Repair for Aneurysmal Chronic Aortic Dissection

PURPOSE

The effectiveness of thoracic endovascular aortic repair (TEVAR) for chronic aortic dissection (AD) with aneurysmal degeneration remains controversial. We retrospectively investigated clinical outcomes and assessed predictors of aortic shrinkage after TEVAR for chronic aneurysmal AD.

MATERIALS AND METHODS

Between January 2010 and December 2021, 70 patients with double-barrel-type chronic AD were enrolled. Major intimal tears in thoracic aorta were covered by stent graft. Early and late clinical outcomes, and diameter change of downstream aorta during follow-up period were reviewed. Subsequently, factors associated with aortic shrinkage were assessed by logistic regression analysis.

RESULTS

Mean age was 63 (interquartile range [IQR]: 54-68) years, 54 (80%) men, median duration from AD onset was 4 (IQR: 1-10) years, and maximum aortic diameter was 53 (IQR: 49-58) mm. Supra-aortic debranching procedure was required in 57 (81%) patients. Early aorta-related death occurred in 2 (3%) patients. Both stroke and spinal cord ischemia occurred in 1 (2%) patient. Five-year freedom rates from aorta-related death and reintervention were 96% and 51%, respectively. Sixty-four patients underwent follow-up computed tomography (84%) 1 year after TEVAR, with 33 (52%) achieving aortic shrinkage. In multivariable analysis, duration from AD onset (per year) (odds ratio [OR]: 0.82, 0.70-0.97; p=0.017) and maximum aortic-diameter ratio between aortic arch and descending aorta (per 0.1) (morphologic index; OR: 1.34, 1.04-1.74; p=0.023) were independent aortic shrinkage predictors.

CONCLUSIONS

Thoracic endovascular aortic repair for chronic AD with aneurysmal degeneration achieved satisfactory survival outcomes, but with a considerable reintervention rate. Duration from AD onset and preoperative aortic morphology could affect post-TEVAR aortic shrinkage. Earlier intervention could lead to better aortic shrinkage.

CLINICAL IMPACT

Thoracic endovascular aortic repair for chronic aortic dissection with aneurysmal degeneration showed low incidence of early and late aorta-related death. By contrast, aortic shrinkage rate was low with high incidence of reintervention to the residual downstream aorta. According to the assessment of preoperative variables, chronicity and aortic morphology could predict postoperative aortic shrinkage.

Endovascular aortic arch repair: A comparison of outcomes and current trends

OBJECTIVE

Application of thoracic endovascular aortic repair (TEVAR) to the aortic arch has been met with the development of purpose-made endoprostheses for on-label use in the aortic arch. An appraisal of the clinical efficacy of each major device is therefore useful towards informing clinical decision making for patients eligible for endovascular arch repair (EAR) rather than open surgical reconstruction.

METHODS

A literature review of publications outlining clinical experience with the RELAY™ Branched and Zenith™ devices was undertaken, and the results therefrom analysed to evaluate the clinical efficacies of each device.

RESULTS

Early- and long-term mortality rates associated with EAR appear favourable, especially compared against open surgical repair. EAR is also associated with good neurological outcomes and target vessel patency rates. However, EAR continues to be associated with substantial reintervention rates.

CONCLUSIONS

At the present stage, EAR represents a promising alternative option to open surgical reconstruction in patients that meet its eligibility criteria. Though there remains a substantial learning curve associated with EAR, its favourable outcome profile is likely to increase its applicability in the future.

Hemodynamic parameters impact the stability of distal stent graft-induced new entry

Stent graft-induced new entry tear (SINE) is a serious complication in aortic dissection patients caused by the stent-graft itself after thoracic endovascular aortic repair (TEVAR). The stability of SINE is a key indicator for the need and timing of reinterventions. This study aimed to understand the role of hemodynamics in SINE stability by means of computational fluid dynamics (CFD) analysis based on patient-specific anatomical information. Four patients treated with TEVAR who developed a distal SINE (dSINE) were included; two patients had a stable dSINE and two patients experienced expansion of the dSINE upon follow-up examinations. CFD simulations were performed on geometries reconstructed from computed tomography scans acquired upon early detection of dSINE in these patients. Computational results showed that stable dSINEs presented larger regions with low time-averaged wall shear stress (TAWSS) and high relative residence time (RRT), and partial thrombosis was observed at subsequent follow-ups. Furthermore, significant systolic antegrade flow was observed in the unstable dSINE which also had a larger retrograde flow fraction (RFF) on the SINE plane. In conclusion, this pilot study suggested that high RRT and low TAWSS may indicate stable dSINE by promoting thrombosis, whereas larger RFF and antegrade flows inside dSINE might be associated with its expansion.

Changing Management of Type B Aortic Dissections

The purpose of this manuscript is to review recent trends in the management of acute type B aortic dissection. Due to its efficacy and low morbidity, thoracic endografting has rapidly been adopted as the treatment of choice for most patients with malperfusion or rupture as a consequence of acute aortic dissection. This technology is increasingly applied to patients without rupture or malperfusion, so-called "uncomplicated" dissections, to reduce the incidence of late aneurysmal degeneration in the ungrafted segments of the thoracoabdominal aorta. A variety of techniques have been proposed, including intentional rupture of the dissection membrane to obliterate the false lumen as well as the candy-plug technique to eliminate retrograde flow in the false lumen.

Aortic arch surgery for type B aortic dissection: How far should we go? The value of a hybrid approach

Traditionally, the management of type B aortic dissection has been the domain of the vascular surgeons. Timing and type of intervention still generate debate. We sought to review our early experience with the treatment of this condition based on a hybrid approach following an aortic multi-disciplinary team meeting involving close cooperation between cardiac surgeons, vascular surgeons, interventional radiologists, vascular anesthetists, and cardiac anesthetists. Four patients (age 41-56 years; 3 males; 1 female) with type B aortic dissection underwent aortic arch surgery through a hybrid approach: one elective procedure consisting of ascending aorta and hemi-arch replacement with debranching followed by thoracic endovascular aortic repair (TEVAR); one redo procedure requiring aortic arch replacement with hybrid frozen elephant trunk; two acute presentations (aortic arch replacement and debranching followed by TEVAR; AVR with ascending aorta, arch, and proximal descending thoracic aorta replacement with conventional elephant trunk and debranching). Deep hypothermic circulatory arrest was required in three patients. Despite respiratory complications and slightly prolonged postoperative course, all patients survived without onset of stroke, paraplegia, malperfusion, endoleak, or need for re-exploration. Follow-up remains satisfactory. Different factors may affect outcome following complex aortic procedures. Nevertheless, close cooperation between cardiac surgeons, vascular surgeons, and interventional radiologists may reduce potential for complications and address aspects that may not be completely within the domain of individual specialists.

Volume Analysis to Predict the Long-Term Evolution of Residual Aortic Dissection after Type A Repair

Background: The aim of this study was to evaluate the aortic diameter and volume during the first year after a type A repair to predict the long-term prognosis of a residual aortic dissection (RAD). Methods: All patients treated in our center for an acute type A dissection with a RAD and follow-up > 3 years were included. We defined two groups: group 1 with dissection-related events (defined as an aneurysmal evolution, distal reintervention, or aortic-related death) and group 2 without dissection-related events. The aortic diameters and volume analysis were evaluated on three postoperative CT scans: pre-discharge (T1), 3−6 months (T2) and 1 year (T3). Results: Between 2009 and 2016, 54 patients were included. Following a mean follow-up of 75.4 months (SD 31.5), the rate of dissection-related events was 62.9% (34/54). The total aortic diameters of the descending thoracic aorta were greater in group 1 at T1, T2 and T3, with greater diameters in the FL (p < 0.01). The aortic diameter evolution at 3 months was not predictive of long-term dissection-related events. The total thoracic aortic volume was significantly greater in group 1 at T1 (p < 0.01), T2 (p < 0.01), and T3 (p < 0.01). At 3 months, the increase in the FL volume was significantly greater in group 1 (p < 0.01) and was predictive for long-term dissection-related events. Conclusion: This study shows that an initial CT scan volume analysis coupled with another at 3 months is predictive for the long-term evolution in a RAD. Based on this finding, more aggressive treatment could be given at an earlier stage.

Thoracic Endovascular Aortic Repair for Chronic Type B Aortic Dissection: Pre- and Postprocedural Imaging

Aortic dissection is a chronic disease that requires lifelong clinical and imaging surveillance, long after the acute event. Imaging has an important role in prognosis, timing of repair, device sizing, and monitoring for complications, especially in the endovascular therapy era. Important anatomic features at preprocedural imaging include the location of the primary intimal tear and aortic zonal and branch vessel involvement, which influence the treatment strategy. Challenges of repair in the chronic phase include a small true lumen in conjunction with a stiff intimal flap, complex anatomy, and retrograde perfusion from distal reentry tears. The role of thoracic endovascular aortic repair (TEVAR) remains controversial for treatment of chronic aortic dissection. Standard TEVAR is aimed at excluding the primary intimal tear to decrease false lumen perfusion, induce false lumen thrombosis, promote aortic remodeling, and prevent aortic growth. In addition to covering the primary intimal tear with an endograft, several adjunctive techniques have been developed to mitigate retrograde false lumen perfusion. These techniques are broadly categorized into false lumen obliteration and landing zone optimization strategies, such as the provisional extension to induce complete attachment (PETTICOAT), false lumen embolization, cheese-wire fenestration, and knickerbocker techniques. Familiarity with these techniques is important to recognize expected changes and complications at postintervention imaging. The authors detail imaging options, provide examples of simple and complex endovascular repairs of aortic dissections, and highlight complications that can be associated with various techniques. Online supplemental material is available for this article. ^©RSNA, 2022.

Favorable neurological outcomes in thoracic endovascular aortic repair with RELAY™ branched-An international perspective

BACKGROUND

While open surgical repair continues to be the mainstay option for aortic arch reconstruction, the associated mortality, morbidity, and high turn-down rates have led to a need for the development of minimally invasive options for aortic arch repair. Though RELAY™ Branched (Terumo Aortic, Inchinnan, UK) represents a promising option for complex endovascular aortic arch repair, neurological complications remain a pertinent risk. Herein we seek to present multicenter data from Europe documenting the neurological outcomes associated with RELAY™ Branched.

METHODS

Prospective data collected between January 2019 and January 2022 associated with patients treated with RELAY™ single-, double-, and triple-branched endoprostheses from centers across Europe was retrospectively analyzed with descriptive and distributive analysis. Follow-up data from 30 days and 6, 12, and 24 months postoperatively were included. Patient follow-up was evaluated for the onset of disabling stroke (DS) and non-disabling stroke (NDS).

RESULTS

Technical success was achieved in 147 (99.3%) cases. Over 24 months period, in total, six (4.1%) patients suffered DS, and eight (5.4%) patients suffered NDS after undergoing aortic arch repair with RELAY™. All patients that developed postoperative DS had been treated with the double-branched RELAY™ endoprosthesis.

DISCUSSION

The data presented herein demonstrates that RELAY™ Branched is associated with favorable neurological outcomes and excellent technical success rates. Key design features of the endoprosthesis and good perioperative management can contribute greatly to mitigating neurological complications following endovascular aortic arch repair.

Adverse complications of frozen elephant trunk, do we have enough quality data?

BACKGROUND

Frozen elephant trunk has in recent times become a mainstay for total arch replacement in aortovascular surgery and is indicated to treat a spectrum of complex aortic pathologies. However, despite associated excellent postoperative results it is incredibly important to recognize potential adverse complications such as negative aortic remodeling, endoleak, and distal stent-graft induced new entry so that outcomes can be further improved.

AIM OF THE STUDY

Below we provide commentary on a recent article in the Journal of Cardiac Surgery discussing the topic.

CONCLUSIONS

Despite the fascinating outcomes of this systematic review and meta-analysis the heterogeneity of the literature regarding these adverse outcomes remains an issue which can only be solved with large multicenter trials directly comparing graft types as well as indications for surgery.

Does endovascular duration impact clinical outcomes in aortic arch repair? The RELAY™ branched international stance

Background

The high mortality and morbidity rates in surgical aortic arch repair are a barrier to therapy for a considerable proportion of patients with aortic arch aneurysm or dissection. There is hence a demand for the development and adoption of a minimally invasive alternative to aortic arch repair, such as thoracic endovascular aortic repair (TEVAR). Procedural duration is a key factor in the pathogenesis of complications in surgical aortic arch repair. Herein, we evaluate whether endovascular duration impacts neurological outcomes, target vessel patency, and reintervention rates in aortic arch TEVAR with RELAY™ Branched (Terumo Aortic, Inchinnan, UK), which is specifically developed for on-label use within the aortic arch.

Methods

Prospective data was collected between January 2019 and January 2022 on the clinical outcomes of TEVAR for aortic arch dissection and aneurysm with RELAY™ single-, double-, and triple branched endoprostheses from centers across Europe. They were then retrospectively analyzed with descriptive and distributive analysis. Follow-up data on the incidence of disabling stroke (DS), target vessel patency, and reintervention from 30 days and 6-, 12-, and 24 months postoperative was included in the analysis.

Results

147 (99.3%) of all 148 cases were successful. Over the 24 month follow-up period, in total 6 (4.1%) patients suffered DS, 24 (16.3%) required reintervention, and target vessel patency was exhibited in 118 (80.2%) patients. The modal endovascular duration was 100-150 min (in 64.6%, n = 95 cases). Analysis revealed that endovascular duration was associated with a lower likelihood of reintervention at 30 days, 6-, and 12 months (P = 0.011, P = 0.019, P = 0.037), a greater likelihood of target vessel patency at 6- and 24 months (P = 0.032, P = 0.035). No relationship between endovascular duration and DS was revealed.

Discussion

The data demonstrates that RELAY™ Branched is associated with promising clinical outcomes for on-label aortic arch TEVAR. The underlying mechanism linking endovascular duration and reintervention rates, or target vessel patency is likely multifactorial and complex. Given that TEVAR is carried out under general anesthetic only, it is unlikely that prolonged procedural duration has any major effect over neurological outcomes for arch TEVAR.

Beta-blocker Use After Thoracic Endovascular Aortic Repair in Patients with Type B Aortic Dissection Is Associated with Improved Early Aortic Remodeling

OBJECTIVE

Beta-blockers are first-line anti-impulse therapy in patients presenting with acute type B aortic dissection (TBAD). However, little is understood about their impact after aortic repair. The aim of this study was to evaluate the role of postoperative beta-blocker use on outcomes of thoracic endovascular aortic repair (TEVAR) in TBAD.

METHODS

The Vascular Quality Initiative database was queried for all patients undergoing TEVAR for TBAD from 2012 to 2020. Aortic-related reintervention, all-cause mortality and effect of TEVAR on false lumen thrombosis of the treated aortic segment were assessed and compared between patients treated with and without beta-blocker postoperatively. Cox proportional hazards models were used to estimate the effect of beta-blocker therapies on outcomes.

RESULTS

1,114 patients undergoing TEVAR for TBAD were identified with a mean follow-up of 18±12 months. The mean age was 61.1±11.9 years, and 791 (71%) were male. 935 (84%) patients were maintained on beta-blocker at discharge and follow-up. Patients on beta-blocker were more likely to have an entry tear originating in zones 1-2 (22% vs 13%; P=.022). The prevalence of acute, elective and symptomatic AD, concurrent aneurysm, number of endografts used, distribution of the proximal and distal zones of dissection and operative time were comparable between the two cohorts. At 18-months, significantly more complete false lumen thrombosis (58 vs 47%; log-rank P=.018) was observed in patients on beta-blocker while the rates of aortic-related reinterventions (13% vs 9%; log-rank P=.396) and mortality (0.2% vs 0.7%; log-rank P=.401) were similar in patients with and without beta-blocker, respectively. Even after adjusting for clinical and anatomic factors, postoperative beta-blocker use was associated with increased complete false lumen thrombosis (HR 1.56; 95% CI: 1.10-2.21; P=.012) but did not affect mortality or aortic-related reintervention. A secondary analysis of beta-blocker use in acute versus chronic TBAD showed a higher rate of complete false lumen thrombosis in patients on beta-blocker in chronic TBAD (59% vs 38%; log-rank P=.038). In contrast, there was no difference in the rate of complete false lumen thrombosis in acute TBAD between the two cohorts (58% vs 51%; log-rank P=.158). When analyzed separately, postoperative ACE inhibitor use did not affect the rates of complete false lumen thrombosis, mortality and aortic-related reintervention.

CONCLUSIONS

Beta-blocker use was associated with promotion of complete false lumen in patients undergoing TEVAR for TBAD. In addition to its role in acute setting, anti-impulse control with beta-blocker appears to confer favorable aortic remodeling and may improve outcomes after TEVAR, particularly for chronic TBAD.

A systematic review and meta-analysis of stroke rates in patients undergoing thoracic endovascular aortic repair for descending thoracic aortic aneurysm and type B dissection

OBJECTIVE

We performed a systematic review and meta-analysis to assess the stroke rates after thoracic endovascular aortic repair (TEVAR) for descending thoracic aortic aneurysms and/or dissections.

METHODS

A systematic search of all the literature reported until September 2021 was performed according to the PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines. The pooled perioperative stroke rates and corresponding 95% confidence intervals (CIs) were estimated using fixed or random effect methods.

RESULTS

A total of 878 study titles were identified by the initial search strategy, of which 43 were considered eligible for inclusion in the meta-analysis. A total of 5764 patients (63.5% male) were identified among the eligible studies. The pooled any stroke rate was 4.4% (95% CI, 3.60%-5.28%). However, after procedures without left subclavian artery (LSA) ostial coverage (eg, TEVAR deployed within or distal to zone ≥3), the stroke rate was 3.15% (95% CI, 2.21%-4.22%). For the patients with LSA coverage, the pooled stroke rate was 2.8% (95% CI, 1.69%-4.14%) for patients receiving left subclavian artery revascularization. However, the patients without LSA revascularization had a pooled estimated stroke incidence of 11.8% (95% CI, 5.85%-19.12%).

CONCLUSIONS

Stroke has been a common finding after TEVAR, especially with LSA coverage without revascularization, validating current clinical practice guidelines recommending routine revascularization, when feasible. Additional studies with larger patient numbers that provide separate data regarding the aortic pathology treated, the anatomic location of the stroke and their association with functional recovery and survival are needed.

Aortic remodeling after endovascular aortic repair and tailored distal entry tears exclusion in Crawford type III or IV dissection aneurysm

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) can only promote 55-80% false lumen (FL) thrombosis when only the proximal primary tear is covered during the repair of type B aortic dissection (TBAD). This study evaluated the effectiveness and clinical outcome of tailored exclusion of the primary entry tear with TEVAR and distal fenestrations with ancillary devices in patients with subacute or chronic Crawford type III and IV aortic dissection aneurysm.

METHODS

All patients underwent either TEVAR for primary entry tear; subsequently, various ancillary devices were applied on each distal fenestration. These techniques included covered stent occlusion of detached visceral artery entry tears, TL stenting and FL occlusion with vascular plugs in the common iliac artery dissection, or TEVAR coverage for multiple fenestrations from segmental arteries. This case series included nine patients (seven men and two women; mean age: 63.4 years) during January 2013 to May 2019. Outcome analysis included the rates of technical success and procedure-related complications, completeness of FL occlusion, aortic remodeling, and midterm mortality at 2 years.

RESULTS

The mean follow-up duration was 37.7 months without in-hospital mortality. One patient was lost to follow-up at the second month, the rest of patients were all alive during the follow-up period. All patients achieved complete FL thrombosis, and six patients exhibited aneurysm diameter shrinkage.

CONCLUSION

Tailored exclusion of visceral and iliac distal fenestrations with proximal primary tear coverage can promote FL thrombosis and aortic remodeling in the visceral aortic segment in patients with Crawford type III or IV aortic dissection aneurysm.

Five-Year Results of Aortic Remodeling for Acute, Subacute, and Chronic Type B Aortic Dissection Following Endovascular Repair

Background

This study was performed to compare aortic remodeling and clinical outcomes in patients with acute, subacute, and chronic type B aortic dissection (TBAD) after thoracic endovascular aortic repair (TEVAR).

Methods

We retrospectively examined 323 consecutive patients with acute (n = 129), subacute (n = 161), and chronic (n = 33) TBAD who underwent TEVAR from June 2013 to December 2016 in in multicenter institution. Patient demographics, clinical data, and imaging characteristics were recorded and compared among the three groups.

Results

The three groups had comparable baseline characteristics. Perioperative mortality rates were similar among the acute (2.3%), subacute (0.0%), and chronic (0.0%) groups (P = 0.34). Perioperative morbidity rates, including the rates of visceral and lower limb malperfusion and cerebral infraction, were also similar. The rate of perioperative endoleak was significantly higher in the chronic group (18.1%) than in the acute (3.9%) and subacute (3.7%) groups (P = 0.02). The mean follow-up duration was 78 ± 22 months (range, 36–101 months). The mortality rates were comparable among the three groups. The rates of reintervention and lower limb malperfusion were higher in the chronic group than in the acute and subacute groups. FL diameter reduction were more robust in the acute and subacute groups than in the chronic group.

Conclusion

Patients with acute, subacute, and chronic TBAD had different outcomes in this study. Patients with acute and subacute TBAD had fewer complications than those with chronic TBAD. Aortic remodeling after TEVAR was more favorable in patients with acute and subacute TBAD than in patients with chronic TBAD. TEVAR promotes more positive remodeling at the stent graft level than at the distal level of the aorta.

The Knickerbocker Technique: Technical Aspects and Single-Center Results of a New Endovascular Method for False Lumen Occlusion in Chronic Aortic Dissection

PURPOSE

To describe the technical aspects and early results of a new endovascular fenestration method for false lumen occlusion in chronic aortic dissection: the Knickerbocker Technique.

METHODS

A retrospective observational study including all consecutively treated patients between November 1, 2012, through May 31, 2016, who underwent thoracic endovascular aortic repair with false lumen occlusion using the Knickerbocker Technique for thoracic false lumen aneurysm in chronic aortic dissection in a tertiary care center. Primary endpoints consisted of technical (correct deployment of the stent-graft) and clinical (false lumen occlusion) success. Secondary endpoints included overall survival and morbidity after 30 days. In 12 patients, follow-up computed tomography angiogram (CTA) was available and aortic remodeling was evaluated.

RESULTS

We identified 16 eligible patients (75% men, mean age: 69 years, range: 52-80 years). Technical success was 94%. Overall survival after 30 days was 100%; there was 1 aortic reintervention (additional false lumen embolization due to endoleak type 1a in 1 patient). Median total follow-up was 31.5 months (range: 3-66 months). Four (25%) of 16 patients died during follow-up, in 3 of those patients the cause of death is unknown, and 1 patient developed cardiac tamponade after being treated by fenestrated thoracic endovascular aortic repair. Imaging follow-up with CTA was available in 12 patients (median imaging follow-up: 27.5 months, range: 1-57 months). Nine (75%) of 12 patients showed thoracic aortic remodeling, and in 3 patients aneurysm size was stable. No patient showed aneurysm growth.

CONCLUSION

The Knickerbocker Technique is a feasible endovascular fenestration method to achieve false lumen occlusion and aortic remodeling in chronic aortic dissection with low invasiveness.

Thoracic endovascular repair of chronic type B aortic dissection: a systematic review

BACKGROUND

At present, the optimal management strategy for chronic type B aortic dissection (CTBAD) remains unknown, as equipoise remains regarding medical management versus endovascular treatment versus open surgery. However, the results over recent years of thoracic endovascular aortic repair (TEVAR) in CTBAD appear promising. The aim of this systematic review was to provide a comprehensive analysis of the available data reporting outcomes and survival rates for TEVAR in CTBAD.

METHODS

Electronic searches of six databases were performed from inception to April 2021. All studies reporting outcomes, specifically 30-day mortality rates, for endovascular repair of CTBAD were identified. Relevant data were extracted, and a random-effects meta-analysis of proportions or means was performed to aggregate the data. Survival data were pooled using data derived from original Kaplan-Meier curves, which allows reconstruction of individual patient data.

RESULTS

Forty-eight studies with 2,641 patients were identified. Early (<30 days) all-cause and aortic-related mortality rates were low at 1.6% and 0.5%, respectively. Incidence of retrograde type A dissection in the post-operative period was only 1.4%. There were also low rates of cerebrovascular accidents and spinal cord injury (1.1% and 0.9%, respectively). Late follow-up all-cause mortality was 8.0%, however, late aortic-related mortality was only 2.4%. Reintervention rates were 10.1% for endovascular and 6.7% for surgical reintervention. Pooled rates of overall survival at 1-, 3-, 5- and 10-year were 91.5%, 84.7%, 77.7% and 56.3%, respectively.

CONCLUSIONS

The significant heterogeneity in the available evidence and absence of consensus reporting standards are important considerations and concern when interpreting the data. Evaluation of the evidence suggests that TEVAR for CTBAD is a safe procedure with low rates of complications. However, the optimal treatment strategy for CTBAD remains debatable and requires further research. Evidence from high-quality registries and clinical trials are required to address these challenges.

Safety of Left Subclavian Artery Selective Coverage without Revascularization in Thoracic Endovascular Aortic Repair for Type B Aortic Dissections

PURPOSE

Whether to proceed left subclavian artery (LSA) revascularization in patients with LSA coverage due to insufficient proximal landing zone (PLZ) during thoracic endovascular aortic repair (TEVAR) remains controversial.

METHODS

A total of 903 patients who received TEVAR were retrospectively analyzed. LSA could be covered if the PLZ was less than 15 mm accompanied with 1) a dominant or balanced right vertebral artery, 2) a complete circle of Willis, and 3) a left vertebral artery with a diameter ≥3 mm and without severe stenosis.

RESULTS

LSA selective coverage was necessary for 35.0% (316/903) of the patients to extend the PLZ. Patients presented with weakness, pain, cooling and discoloration of the left upper extremity (LUE), and pulselessness of the left brachial artery were more in the LSA-covered group. The ischemia of LUE occurred more often in patients with LSA covered completely than in those with LSA covered partially. Functional arm status showed no significant difference in the arm, shoulder, and hand questionnaire scores at 12 months postoperative between the LSA-covered group and LSA-uncovered group, or between the LSA-covered completely group and LSA-covered partially group.

CONCLUSION

It was safe to cover the LSA origin without revascularization if the PLZ was less than 15 mm accompanied with careful evaluation (description in method).

Spontaneous Isolated Dissection of Iliac Artery Treated with Endovascular Repair: A Case Report

Spontaneous isolated dissection of the iliac artery (SID-IA) is a rare pathologic condition. The predisposing factors and best treatment strategies are still being debated. We present the case of a 59-year-old male with acute right lower limb ischemia characterized by the sudden occurrence of rest pain, hypoesthesia, and paresis. Angiography showed SID-IA extending down to the femoral bifurcation. The patient had no risk factors for SID-IA; however, he survived an electrocution and had arterial hypertension at admission. Endovascular revascularization was successfully performed, with complete restoration of limb blood flow and remission of symptoms. Follow-up ultrasonography at 1 year confirmed stent patency and absence of clinical symptoms. Endovascular stenting is a good therapeutic option for symptomatic SID-IA without rupture.

Endovascular repair of acute complicated type B aortic dissection-systematic review and meta-analysis of long-term survival and reintervention

Background

Thoracic endovascular repair (TEVAR) is considered the first-line therapy in the repair of acute complicated type B aortic dissection (AC-BAD). Given the difficulty of designing randomized trials in this surgical cohort, long-term outcome data is limited. This systematic review and meta-analysis provide a complete aggregation of reported long-term survival and freedom from reintervention of AC-BAD patients based on the existing literature.

Methods

Three databases were searched from date of database inception to January 2021. The relevant references were identified and baseline cohort characteristics, survival and freedom from reintervention were extracted. The primary endpoints were survival and freedom from reintervention, whilst secondary endpoints were post-operative outcomes such as cord ischemia and endoleak. Kaplan-Meier curves were digitized and aggregated as per established procedure.

Results

A total of 2,812 references were identified in the literature search for review, with 46 selected for inclusion. A total of 2,565 patients were identified, of which 1,920 (75%) were male. The mean age of the cohort was 59.8±5.8. Actuarial survival at 2, 4, 6 and 10 years was 87.5%, 83.2%, 78.5% and 69.7%, respectively. Freedom from all secondary reintervention at 2, 4, 6, 8 and 10 years was 74.7%, 69.1%, 65.7%, 63.9% and 60.9%, respectively. When accounting for study quality, actuarial survival at 2, 4, 6 and 8 years was 85.4%, 79.1%, 69.8% and 63.1%, respectively. Freedom from all secondary reintervention at 2, 4, 6 and 8 years was 73.2%, 67.6%, 63.7% (maintained), respectively.

Conclusions

TEVAR is associated with promising long-term survival extended to 10 years, though rates of freedom from reintervention remain an ongoing point for improvement. Randomized controlled trials comparing endovascular with open repair in the setting of acute, complicated type B aortic dissection are needed.

Surgical Strategy for Chronic Type B Dissecting Aortic Aneurysm to Prevent Aorta-Related Events

BACKGROUND

This study was aimed to evaluate the outcomes of performing open repair or thoracic endovascular aortic repair for chronic type B dissecting aortic aneurysm.

METHODS

From July 2004 to February 2019, 52 patients underwent surgery as open repair (n = 32) or endovascular repair (n = 20) for chronic type B dissecting aortic aneurysm. Replacement of the aorta was limited to the aneurysmal portion with or without reconstructing the visceral arteries or the segmental arteries. Stent grafts were deployed in the true lumen above the celiac artery to cover the primary entry for even DeBakey IIIb dissection.

RESULTS

Operative mortality and morbidity rates, including spinal cord ischemia incidence, did not differ between the groups. Operative mortality and morbidity rates, including spinal cord ischemia incidence, did not differ between the groups. In the endovascular repair group, 3 patients died due to rupture of residual false lumen in the early, and late postoperative follow-up. The 5-year rate of freedom from all-cause death, aorta-related death, and aorta-related event were 84% ± 6%, 94% ± 3% and 84% ± 6%. The endovascular repair was independently associated with all-cause death (hazard ratio [HR], 5.7; confidence interval [CI], 1.02-31.6; P = 0.04) and aorta-related event (HR, 30.9; CI 4.9-195.0; P < 0.001). In the open group, postoperative residual aortic diameter was an independent predictor of aorta-related events, and the threshold was 41 mm.

CONCLUSIONS

Open repair remains a better option than simple endovascular repair alone in DeBakey IIIb dissection, but the distal un-resected aortic portion over 41 mm was associated with late aortic events.

Use of ASD closure device for the sealing of false lumen entry in the ascending aorta after dissection Type A surgical repair

We present a case of a persistent false lumen after ascending aorta replacement due to Stanford Type A dissection treated by endovascular means. The main entry tear was occluded with an atrial septal defect closure device, sealing the false lumen. A total of five additional stents were implanted to centralise and secure the flow in the true lumen. CT scan at 6-month follow-up showed excellent results with a decreased total aortic diameter and thrombosed false lumen.

Results of a prospective follow-up study after type A aortic dissection repair: a high rate of distal aneurysmal evolution and reinterventions

OBJECTIVES

We investigated the anatomical evolution of residual aortic dissection after type A repair and factors associated with poor prognosis at a high-volume aortic centre.

METHODS

Between 2017 and 2019, all type A aortic dissections were included for prospective follow-up. Patients without follow-up computed tomography (CT) scan available for radiological analysis and patients without residual aortic dissection were excluded from this study. The primary end point was a composite end point defined as dissection-related events including aneurysmal evolution (increased diameter > 5 mm/year), aortic reintervention for malperfusion syndrome, aortic diameter >55 mm, rapid aortic growth >10 mm/year or aortic rupture and death. The secondary end points were risk factors for dissection-related events and reintervention analysis. All immediate and last postoperative CT scans were analysed.

RESULTS

Among 104 patients, after a mean follow-up of 20.4 months (8-41), the risk of dissection-related events was 46.1% (48/104) and the risk of distal reintervention was 17.3% (18/104). Marfan syndrome (P < 0.01), aortic bicuspid valve (P = 0.038), innominate artery debranching (P = 0.025), short aortic cross-clamp time (P = 0.011), initial aortic diameter >40 mm (P < 0.01) and absence of resection of the primary entry tear (P = 0.015) were associated with an increased risk of dissection-related events or reintervention during follow-up.

CONCLUSIONS

Residual aortic dissection is a serious disease requiring close follow-up at an expert centre. This study shows higher reintervention and aneurysmal development rates than currently published. To improve long-term outcomes, the early demographic and anatomic poor prognostic factors identified may be used for more aggressive treatment at an early phase.

TEVAR for complicated and uncomplicated type B aortic dissection-Systematic review and meta-analysis

BACKGROUND

Type B aortic dissection (TBAD), is defined as a dissection involving the aorta distal to left subclavian artery with the ascending aorta and the aortic arch not affected. TBAD is classified due to the time frame and presence of complications. Complicated TBAD (co-TBAD) patients have a greater mortality rate than uncomplicated TBAD (un-TBAD) and thoracic endovascular aortic repair (TEVAR) is considered the gold-standard intervention for these clinical challenges.

METHODS

We undertook a systematic review of the literature regarding TEVAR intervention in co-TBAD and un-TBAD. A comprehensive search was undertaken across four major databases and was evaluated and assessed until June 2020.

RESULTS

A total of 16,104 patients were included in the study (7772 patients co-TBAD and 8352 un-TBAD). A significantly higher proportion of comorbidities were seen in co-TBAD patients compared with un-TBAD. Acute dissection was more frequent in the co-TBAD group (73.55% vs. 66.91%), while chronic dissection was more common in un-TBAD patients (33.8% vs. 70.73%). Postprocedure stroke was higher in co-TBAD (5.85% vs. 3.92%; p < .01), while postprocedural renal failure was higher in un-TBAD patients (7.23 vs. 11.38%; p < .01). No difference was observed in in-hospital mortality however the 30 days mortality was higher in the co-TBAD group. One-year survival was higher in the uncomplicated group but this difference was not observed in the 5-year survival.

CONCLUSION

In our analysis we can appreciate that despite significantly higher comorbidities in the co-TBAD cohort, there was no difference in in-hospital mortality between the two groups and the 5-year survival did not have any difference.

Retrospective analysis of factors associated with aortic remodeling in patients with Stanford type B aortic dissection after thoracic endovascular aortic repair

Objective

Acute aortic dissection is a life-threatening condition. Thoracic endovascular aortic repair (TEVAR), together with optimized medical treatment, is currently the first line treatment for acute Stanford type B aortic dissection. TEVAR can close the entry tear and reduce mortality. Aortic remodeling after TEVAR can directly affect the patient’s long-term prognosis. The factors that influence aortic remodeling have, however, received insufficient clinical attention and remain unclear. It is very important to identify these factors.

Methods

A total of 100 patients were continuously enrolled from 2011 to 2018 in 2 centers. Relevant data, including time from hospital admission to surgery, medicine use and aortic computed tomography angiography images obtained before and 6 months after surgery were collected. Patients were divided into favorable and adverse aortic remodeling groups, according to the degree of aortic remodeling. Analysis of variance and the chi-square test were performed using SPSS software to compare differences between groups and to determine the factors that influence postoperative aortic remodeling.

Results

The proportion of single-stent implantations was higher in the favorable remodeling group than in the adverse remodeling group (79.5% vs. 53.8% in distal end of stent-graft level and 81.3% vs. 56.4% in diaphragm level, respectively, p < 0.05). The earlier the TEVAR procedure was performed, the better the aortic remodeling (3.4 days vs. 4.8 days in distal stent graft levels, and 3.6 days vs. 4.9 days in diaphragm level, respectively, p < 0.05), the presence of residual distal entry tears in the abdominal aorta also improved aortic remodeling after TEVAR (85.7% vs. 55.1% in the celiac trunk level, and 92.0% vs. 48.9% in the right renal artery level, respectively, p < 0.05).

Conclusion

Single stent-graft implantation and early surgery were associated with favorable aortic remodeling. Distal entry tears were also conducive to aortic remodeling after surgery for aortic dissection.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13019-021-01571-2.

Anticoagulation and Antiplatelet Medications Do Not Affect Aortic Remodeling after Thoracic Endovascular Aortic Repair for Type B Aortic Dissection

OBJECTIVE

There is a lack of evidence regarding the effect of anticoagulation and antiplatelet medications on aortic remodeling for aortic dissection after endovascular repair. We investigated whether anticoagulation and antiplatelet medications affect aortic remodeling after thoracic endovascular aortic repair (TEVAR) for Type B aortic dissection (TBAD).

METHODS

Records of the Vascular Quality Initiative TEVAR registry (2012-2020) were reviewed. Procedures performed for TBAD were included. Aortic reintervention, false lumen thrombosis of the treated aorta and all-cause mortality at follow-up were compared between patients treated with and without anticoagulation medications. A secondary analysis was performed to assess the effect of antiplatelet therapy in patients not on anticoagulation. Cox proportional hazards models were used to estimate the effect of anticoagulation and antiplatelet therapies on outcomes.

RESULTS

1,210 patients (mean age, 60.7±12.2 years; 825 (68%) males) were identified with a mean follow-up of 21.2±15.7 months (range 1-94 months). 166 (14%) patients were on anticoagulation medications at discharge and at follow-up. Patients on anticoagulation were more likely to be older (mean age, 65.5 vs 60 years; P<.001) and Caucasian (69% vs 55%; P=.003), with higher proportions of coronary artery disease (10% vs 3%; P<.001), congestive heart failure (10% vs 2%; P<.001) and chronic obstructive pulmonary disease (15% vs 9%; P=.017). There were no differences in the mean preoperative thoracic aortic diameter or the number of endografts used. At 18-month, the rates of aortic reinterventions (8% vs 9% log-rank P=.873), complete false lumen thrombosis (52% vs 45%; P=.175) and mortality (2.5% vs 2.7%; P=.209) were similar in patients with and without anticoagulation, respectively. Controlling for covariates with the Cox regression method, anticoagulation use was not independently associated with a decreased rates of complete false lumen thrombosis (hazard ratio (HR) 0.74; 95% confidence interval (CI), 0.5-1.1; P=.132), increased need for aortic reinterventions (HR 1.02; 95% CI, 0.62-1.68; P=.934), and mortality (HR 1.25; 95% CI, 0.64-2.47; P=.514). On a secondary analysis, antiplatelet medications did not affect the rates of aortic reintervention, complete false lumen thrombosis and mortality.

CONCLUSIONS

Anticoagulation and antiplatelet medications do not appear to negatively influence the midterm endpoints of aortic reintervention or death in patients undergoing TEVAR for TBAD. Moreover, it did not impair complete false lumen thrombosis. Anticoagulation and antiplatelet medications do not adversely affect aortic remodeling and survival in this population at midterm.

Timing and Outcome of Endovascular Repair for Uncomplicated Type B Aortic Dissection

OBJECTIVE

This study aimed to determine the effect of intervention timing, from symptom onset to thoracic endovascular aortic repair (TEVAR), on early and late outcomes in high risk patients with uncomplicated type B aortic dissection (uTBAD).

METHODS

The study retrospectively evaluated 267 uTBAD patients with high risk radiographic features who underwent pre-emptive TEVAR during the acute and subacute periods. Demographics, comorbidities, pre-operative imaging features, peri-procedural details, and follow up outcomes were analysed.

RESULTS

Among the 267 pre-emptive TEVARs for high risk uTBAD, 130 were performed in the acute phase (1-14 days); and 137 in the subacute phase (15-90 days), from initial presentation. The mean age was 55.9 ± 11.0 years and 222 (83.1%) were men. The 30 day mortality rate in the acute group was five times higher than that in the subacute group (3.8% vs. 0.7%), although without statistically significant difference (p = .11). No statistically significant difference in 30 day outcomes (aortic rupture, retrograde type A dissection [RTAD], immediate type Ia endoleak, stroke, spinal cord ischaemia, and re-intervention) was noted (p > .05 for each). Of note, aortic rupture, RTAD, and disabling stroke were observed only in the acute group. Multivariable logistic analyses showed that intervention timing was not associated with 30 day outcomes. The median clinical follow up was 48.2 ± 25.9 months (range 1 - 106 months). There were no significant differences in all cause mortality, dissection related death, late intervention, or aortic related late events among timing cohorts (p > .05 for each). Furthermore, aortic remodelling, by analysing the flow status of the false lumen and evaluation of aortic diameters, either at the thoracic aorta level or the abdominal aorta level, was similar between the two groups. Multivariable Cox analyses showed that intervention timing was not associated with late outcomes.

CONCLUSION

The present study indicates that TEVAR for high risk uTBAD in the acute phase was associated with a trend toward higher rates of early complications, while the long term outcomes were comparable with those of the subacute phase.

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

BACKGROUND

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

METHOD

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

RESULTS

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

CONCLUSION

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

A 10-Year Aortic Center Experience with Hybrid Repair of Chronic "Residual" Aortic Dissection After Type A Repair

PURPOSE

Hybrid aortic arch repair in patients with chronic residual aortic dissection (RAD) is a less invasive alternative to conventional surgical treatment. The aim of this study was to describe the short-term and long-term results of hybrid treatment for RAD after type A repair.

METHODS

In this retrospective single-center cohort study, all patients treated for chronic RAD with hybrid aortic arch repair were included. Indications for treatment were rapid aortic growth, aortic diameter > 55 mm, or aortic rupture.

RESULTS

Between 2009 and 2020, we performed 29 hybrid treatments for chronic RAD. Twenty-four patients were treated for complete supra-aortic debranching in zones 0 and 5 with left subclavian artery debranching alone in zone 2. There was 1 perioperative death (3.4%): The patient was treated for an aortic rupture. There was no spinal cord ischemia and 1 minor stroke (3.4%). After a median follow-up of 25.4 months (range 3-97 months), the long-term mortality was 10.3% (3/29) with no late aortic-related deaths. Twenty-seven patients (93.1%) developed FL thrombosis of the descending thoracic aorta; the rate of aneurysmal progression on thoraco-abdominal aorta was 41.4% (12/29), and the rate of aortic reintervention was 34.5% (10/29).

CONCLUSION

In a high-volume aortic center, hybrid repair of RAD is associated with good anatomical results and a low risk of perioperative morbidity and mortality, including that of patients treated in zone 0. A redo replacement of the ascending aortic segment is sometimes necessary to provide a safer proximal landing zone and reduce the risk of type 1 endoleak after TEVAR.

3D Morphologic Findings Before and After Thoracic Endovascular Aortic Repair for Type B Aortic Dissection

BACKGROUND

Stanford type-B aortic dissection (TBAD) is commonly treated by thoracic endovascular aortic repair (TEVAR). Usually, the implanted stent-grafts will not cover the entire dissection-affected region for those patients with dissection extending beyond the thoracic aorta, thus the fate of the uncovered aortic segment is uncertain. This study used 3-dimensional measurement of aortic morphological changes to classify the different remodeling effects of TBAD patients after TEVAR, and hypothesized that not only initial morphological features, but also their change over time at follow-up are associated with the remodeling.

METHODS

Forty-one TBAD patients underwent TEVAR and CT-angiography before and after the intervention (twice or more follow-ups) were included in this study. According to the false-lumen volume variations post-TEVAR, patients who had abdominal aortic expansion at the second follow-up were classified into the Enlarged (n =12, 29%) and remaining into the Stable group (n = 29, 71%). 3D morphological parameters were extracted on precise reconstruction of imaging datasets. Statistical differences in 3D morphological parameters over time between the 2 groups and the relationship among these parameters were analyzed.

RESULTS

In the Enlarged group, the number of all tears before TEVAR was significantly higher (P = 0.022), and the size of all tears at the first and second follow-up post-TEVAR were significantly higher than that in the Stable group (P = 0.008 and P = 0.007). The location of the primary tear was significantly higher (P = 0.031) in the Stable group. The cross-sectional analysis of several slices below the primary tear before TEVAR shows different shape features of the false lumen in the Stable (cone-like) and Enlarged (hourglass-like) groups. The number of tears before TEVAR has a positive correlation with the post-TEVAR development of dissection (r = 0.683, P = 0.00).

CONCLUSION

The results in this study indicated that the TBAD patients with larger tear areas, more re-entry tears and with the primary tear proximal to the arch would face a higher risk of negative remodeling after TEVAR.

Aortic remodelling after thoracic endovascular aortic repair in acute and chronic type B aortic dissections

OBJECTIVES

Type B aortic dissections are routinely treated with thoracic endovascular aortic repair (TEVAR). The timing for TEVAR remains controversial and might have an impact on the remodelling capacity of the aorta. This study analyses and compares aortic remodelling in acute (ABD) and chronic (CBD) type B aortic dissections after TEVAR.

METHODS

This retrospective study analysed the preoperative, postoperative and at least 1-year follow-up computed tomography of 53 TEVAR patients (36 ABD, 17 CBD) at a single institution between May 2005 and May 2016. The volumes of aortic lumen (AL), true lumen, false lumen (FL) and perfused FL were measured at the stent graft level (A), from the stent graft to the coeliac trunk (B) and from the coeliac trunk to the bifurcation (C). The absolute volumes, normalized volume changes and FL thrombosis rate of ABD and CBD patients were compared.

RESULTS

Absolute AL and FL of segment A were significantly larger in CBD patients compared to ABD patients preoperatively (AL: 354 ± 68 vs 255 ± 51 ml, P = 0.023, FL: 253 ± 56 vs 183 ± 35 ml, P = 0.028) until last follow-up (AL: 462 ± 52 vs 246 ± 52 ml, P = 0.003, FL: 268 ± 202 vs 91 ± 31 ml, P = 0.004). The true lumen in segment A increased more in ABD than in CBD patients preoperatively to postoperatively (112% vs 36% P < 0.001) and within the first year postoperatively (171% vs 80% P < 0.001). FL in segment A decreased more in ABD compared to CBD patients within the first year (-42% vs -13% P < 0.001) and thereafter (-50% vs +6% P = 0.002). In segments B and C, the FL thrombosis rate was higher in ABD than in CBD patients at all time points and significantly higher in segment A after the first year (91% vs 98% P = 0.035).

CONCLUSIONS

Aortic remodelling after TEVAR is significantly different in acute and chronic dissection patients. TEVAR promotes aortic remodelling in both acute and chronic dissections in terms of true lumen increase at stent graft level. Nevertheless, significant AL reduction by FL shrinkage is primarily found in ABD.

Management of acute type B aortic dissection

BACKGROUND

The best management of acute uncomplicated type B aortic dissection is currently a controversial area. Recent advances in endovascular intervention have begun to establish pre-emptive thoracic endovascular aortic repair as a potential strategy. A review about the management for type B aortic dissection has been conducted.

METHODS

A narrative review consisting of 157 original articles, meta-analyses and guidelines was conducted. The findings were synthesized and summarized using 70 articles.

RESULTS

There are clear guidelines directing surgical management of acute complicated type B aortic dissection. However, the best management of acute uncomplicated disease is more ambiguous, which is especially concerning in a condition which is associated with significant morbidity and mortality. Medical management alone is generally favoured. Endovascular intervention is now being considered by some surgeons, but it can be technically difficult, while exposing the patient to potential surgical risks.

CONCLUSIONS

Clinical and anatomical risk factors have been identified to help vascular surgeons make decisions about treatment in acute uncomplicated type B aortic dissection. New endovascular strategies are being developed to reduce surgical risk and address technical challenges. Registry data should be used to support future best management.

Clinical and Morphologic Outcomes of Endovascular Repair for Subacute and Chronic Type B Aortic Dissection

BACKGROUND

The objective of the study was to assess long-term remodeling, survival, and reintervention outcomes after thoracic endovascular aortic repair (TEVAR) for subacute and chronic type B aortic dissection (TBAD).

METHODS

All patients who underwent TEVAR for subacute or chronic TBAD at a tertiary referral center between 1999 and 2015 were included in this cohort study. The primary outcome was aortic remodeling, and secondary outcomes included survival, rate of major complications, and reinterventions.

RESULTS

Fifty patients were included, with mean age of 62.4 years, 10 (20%) DeBakey type IIIA and 40 (80%) DeBakey type IIIB dissection; 45 standard TEVAR, 2 branched TEVAR, 3 TEVAR combined with fenestrated or branched EVAR. Indication for TEVAR was intact (n = 40) or ruptured (n = 1) postdissection aneurysm, hypoperfusion (n = 4), treatment-refractory pain (n = 2), or a combination (n = 3). Mean clinical follow-up was 76 months, and median radiological follow-up was 46 months. Thirty-day survival was 96%, stroke 4%, renal failure 0%, paraplegia 0%. Three- and five-year survival was 92% (95% confidence interval (CI) [79; 97]) and 77% (95% CI [61; 87]), respectively. Of 19 late deaths, 6 were confirmed aorta related. Five-year freedom from reintervention was 69% (95% CI [53-80]). Distal stent graft extension due to aortic dilatation composed most reinterventions. Mean maximal aortic diameter was 58.7 mm preoperatively and 51.9 mm on last follow-up (P = 0.003). On thoracic level, true lumen expanded (+10.0 mm, 95% CI [6.4; 13.6]) (P < 0.001) and false lumen decreased (-11.9 mm, 95% CI [-15.2; -8.5]) (P < 0.001) from baseline to the last computed tomography. In the abdominal aorta, true lumen diameter change was +3.1 mm (95% CI [1.4; 4.8]) (P = 0.001); false lumen diameter change was +1.0 mm (95% CI [-1.8; 3.8]) (P = 0.464).

CONCLUSIONS

TEVAR for subacute and chronic TBAD results in favorable remodeling of the thoracic but not the abdominal aorta. Five-year survival is almost 80%, but late aortic deaths still occur. Aortic dilatation distal to the treated segment requiring reintervention is common, emphasizing the importance of follow-up.