Five-year results of the STABLE II study for the endovascular treatment of complicated, acute type B aortic dissection with a composite device design

Bioabsorbable Stent-Covering with Sustained Anticoagulant Activity Fabricated via Alternate Layer-by-Layer Self-Assembly of Heparin and Silk Fibroin

For severe local vasculopathy, covered stents are considered the major medical devices in interventional therapy due to their function to isolate lesions and deliver drugs. However, commercial stent-coverings have unsatisfactory drug-loading capacity and lack bioactivity. Silk fibroin (SF) possesses excellent biocompatibility, biodegradability, and endothelialization ability. In this study, we developed a bioabsorbable SF stent-covering loaded with heparin (Hep) via layer-by-layer self-assembly. Hep was embedded in the stent-covering via interfacial adsorption (Hep-SF) or direct blending with SF (Hep/SF). For interfacial adsorption, the Hep loading capacity increased with adsorption time and Hep concentration, reaching up to 589 μg/cm2. All Hep-modified SF stent-coverings were nonhemolytic. After Hep modification, the recalculation time of the Hep-SF stent-covering was significantly prolonged (>2 h), platelet adhesion to its surface was reduced, and no obvious clots formed. Compared to the Hep/SF stent-coverings, the release quantity of Hep from the Hep-SF stent-covering was higher at each time point, regardless of diffusion or enzymatic degradation, but its diffusion release rate was lower than that of the high-dosage Hep/SF stent-covering, suggesting that the Hep-SF stent-covering had more sustained Hep release. Moreover, the released Hep maintained a high anticoagulant activity to significantly prolong activated partial thromboplastin time and thrombin time after long-time diffusion or enzymatic degradation. The results indicated that the Hep-SF stent-covering developed in this study not only had a high loading capacity for anticoagulant drugs (on-demand adjustable) but also could achieve effective and sustained anticoagulant function until the SF material was completely degraded.

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.

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.

Long-Term Volumetric Evaluation of Stent-Assisted Balloon-Induced Intimal Disruption and Relamination of Aortic Dissection (STABILISE) in Acute Type B Aortic Dissection

BACKGROUND

To quantify the volumetric aortic remodeling of patients with acute type B aortic dissection treated with the stent-assisted balloon-induced intimal disruption and relamination (STABILISE) technique.

METHODS

All patients with acute type B aortic dissection operated with the STABILISE technique between 2014 and 2017 with preoperative, postoperative, and >12 months (follow-up) computed tomography scans were included in this study. True lumen and total aortic volume were accurately assessed in the thoracic and abdominal portions with a semiautomatic three-dimensional tool. Associations with long-term adverse events were estimated.

RESULTS

Seventeen patients were measured at preoperative, postoperative, and a mean follow-up of 19 ± 8 months. The false lumen to total volume ratio decreased on average from 63% to 18% after STABILISE (P < 0.001) and remained around 12% at follow-up. These remodeling was more pronounced in the thoracic aorta (7%) than in the abdominal aorta (28%). The trend in aortic size growth was stronger for volumes than for maximum areas or diameters (P < 0.001, P < 0.05, and P < 0.05, respectively). Adverse events were identified in 4 patients during a long-term follow-up of 76 ± 18 months. The only aortic size variable assessed preoperatively that was associated with undesirable events was the total volume of the abdominal aorta (P < 0.05).

CONCLUSIONS

A volumetric analysis of dissected aortic size after the STABILISE procedure allowed accurate quantification of mid-term aortic remodeling and helped to identify the abdominal aortic volume as a preoperative variable associated with undesirable long-term events.

Evaluation of Thoracic Endovascular Repair for the Treatment of Type B Aortic Dissection Complicated by Malperfusion

Objectives: This study aims to investigate the efficacy of thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD) complicated by malperfusion. Methods: This retrospective study included patients who underwent TEVAR for the treatment of TBAD complicated by malperfusion from June 1998 to June 2022 in four institutions. In addition to the common outcomes, including short- and medium-term mortality and morbidity, the preservation of each organ was investigated. Results: A total of 23 patients were included in this analysis. The 30-day mortality was 4% (1/23) of the patients. The overall survival rate was 87% at 1 year. The preservation rate of each organ was 33% (4/12) for the visceral organs, 85% (17/20) for the kidneys, and 100% (18/18) for the legs. Fisher's exact test showed a significant difference in the preservation rate between the viscera and the other organs (P = 0.018 vs. kidneys, P = 0.0025 vs. legs). It was shown that the survival rate of patients with visceral malperfusion was significantly lower than that of patients with non-visceral malperfusion (P = 0.006). Conclusion: In terms of mortality, TEVAR showed satisfactory results. The preservation of visceral organs was still challenging even with TEVAR and adjunctive measures.

Navigating clinical appropriateness: A review of management strategies for type B aortic dissection

Aortic dissection is a catastrophic, life-threatening event. Its management depends on the anatomic location of the intimal tear (type A v B) and the clinical presentation in type B aortic dissection. In this article, the current evidence supporting clinical practice, gaps in knowledge, and the need for more rigorous research and higher-quality studies are reviewed.

Volumetric analysis in primary and residual type B aortic dissection treated with stented-assisted balloon-induced intimal disruption and relamination technique can predict aortic reintervention

OBJECTIVE

The aim of this study was to investigate the mid-term results of stented-assisted balloon-induced intimal disruption and relamination (STABILISE) in patients with aortic dissection with the implementation of volumetric analysis.

METHODS

This was a single-center retrospective analysis of prospectively collected data. From May 2017 to September 2022, 42 patients underwent STABILISE for acute complicated or subacute high-risk aortic dissection. STABILISE was completed with distal extended endovascular aortic repair in 24 patients. A computed tomography scan was performed at baseline, before hospital discharge, and at 1, 3, and 5 years. Perfused total aortic, true lumen, and false lumen volumes were assessed for thoracic, visceral, and aorto-iliac segment. The ratio between false lumen and total volume was named perfusion dissection index (PDI). Complete remodeling was defined as PDI = 0, and positive remodeling as PDI ≤0.1.

RESULTS

Technical success was 97.6%. No 30-day deaths, spinal cord injuries, or retrograde dissections were observed. Mean follow-up was 44 ± 19.4 months. Thoracic diameter was lower at last available computed tomography scan (36.7 vs 33.0 mm; P = .01). Aortic growth >5 mm was observed in 9.5% of the patients. Thoracic and visceral aortic complete remodeling were 92.8% and 83.3%, respectively, with no difference between acute and subacute group. Distal extended endovascular aortic repair significantly increased complete remodeling in the aorto-iliac segment, compared with STABILISE alone (69.6% vs 21.4%; P < .001). Freedom from vascular reinterventions at 3 years was 83.1% (95% confidence interval, 71.5%-96.6%). Total PDI ≤0.1 at first postoperative control was a predictor of vascular reinterventions (P < .0001).

CONCLUSIONS

STABILISE is a safe and feasible technique associated with high mid-term rates of complete remodeling in the thoracic and visceral aorta. Volumetric analysis allows the quantification of aortic remodeling and represents a predictor of aortic reinterventions.

Extended thoracic endovascular aortic repair is optimal therapy in acute complicated type B dissection

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) represents optimal therapy for complicated acute type B aortic dissection (aTBAD). Persistent knowledge gaps remain, including the optimal length of aortic coverage, impact on distal aortic remodeling, and fate of the dissected abdominal aorta.

METHODS

Review of the Emory Aortic Database identified 92 patients who underwent TEVAR for complicated aTBAD from 2012 to 2018. Standard TEVAR covered aortic zones 3 and 4 (from the left subclavian to the mid-descending thoracic aorta). Extended TEVAR fully covered aortic zones 3 though 5 (from the left subclavian to the celiac artery). Long-term imaging, clinical follow-up, and overall and aortic-specific mortality were reviewed.

RESULTS

Extended TEVAR (n = 52) required a greater length of coverage vs standard TEVAR (n = 40) (240 ± 32 mm vs 183 ± 23 mm; P < .01). In-hospital mortality occurred in 5.4% of patients (7.7% vs 2.5%; P = .27) owing to mesenteric malperfusion (n = 3) or rupture (n = 2). The overall incidences of postoperative stroke, transient paraparesis, paraplegia, and dialysis were 5.4% (3.9% vs 7.5%; P = .38), 3.2% (5.8% vs 0%; P = .18), 0%, and 0% respectively, equivalent between groups. Follow-up was 96.6% complete to a mean of 6.1 years (interquartile range, 3.5-8.6 years). There were significantly higher rates of complete thrombosis or obliteration of the entire thoracic false lumen after Extended TEVAR (82.2% vs 51.5%; P = .04). Distal aortic reinterventions were less frequent after extended TEVAR (5.8% vs 20%; P = .04). Late aorta-specific survival was 98.1% after extended TEVAR vs 92.3% for standard TEVAR (P = .32).

CONCLUSIONS

Extended TEVAR for complicated aTBAD is safe, results in a high rate of total thoracic false lumen thrombosis/obliteration, and reduces distal reinterventions. Longer-term follow-up will be needed to demonstrate a survival benefit compared to limited aortic coverage.

Endovascular treatment for thoracic aortic disease from the Global Registry for Endovascular Aortic Treatment

OBJECTIVE

Global Registry for Endovascular Aortic Treatment (GREAT) is an international prospective multicenter registry collecting real-world data on performance of W. L. Gore thoracic and abdominal aortic endografts. This analysis evaluated the long-term differences in patient survival and device performance in patients undergoing thoracic endovascular aortic repair (TEVAR) for any thoracic aortic pathology.

METHODS

From August 2010 to October 2016, 5014 patients were enrolled in GREAT. The population of interest was comprised of only patients treated for thoracic aortic pathologies. Through 5 years, primary outcomes were all-cause and aortic-related mortality, stroke, aortic rupture, endoleaks, migration, fracture, compression, paraplegia, and any reintervention through 5 years, grouped by pathology. Secondary outcomes were reintervention rate and freedom from serious device- and aortic-related events.

RESULTS

The 578 patients with thoracic aortic pathologies enrolled in GREAT and identified for this analysis were categorized by common pathologies: thoracic aneurysm (n = 239), thoracic dissection (n = 203), arch (n = 26), and other (n = 110). The mean age of this population was 66.1 ± 12.8 years, and 64.7% were male. Procedure survival was 99.7%. In the overall group, at index procedure to 30 days and 31 days to 5 years, Kaplan-Meier estimates of freedom from all-cause mortality were 99.6% and 66.4%, respectively, and for aortic-related mortality were 97.7% and 94.6%, respectively. Aortic rupture rate was 0.5% (n = 3) at 30 days and 1.4% (n = 8) through 5 years. Stroke and spinal cord ischemic events were 1.9% (n = 11) and 1.6% (n = 9) at 30 days and at 5 years were 3.6% (n = 20), 0.5% (n = 3), respectively. Reinterventions were required in 7.3% (n = 42) at 30 days and 12.4% (n = 69) through 5 years. The number of patients with endoleaks at 30 days was 2.1% (n = 12): n = 3 (1.1%) for each of types IA, 1B, and II; n = 2 (0.3%) for type III; and n = 4 (0.7%) for unspecified. Through 5 years, the percentage of patients was 8.3% (n = 40): n = 15 (3.1%) for type IA; n = 10 (2.1%) for type IB; n = 11 (2.3%) for type II; and n = 9 (1.9%) for unspecified. One patient (0.2%) had stent migration at 30 days (aneurysm group); none were reported through 5 years. There were no incidents of stent compression or fracture from index procedure through 5 years.

CONCLUSIONS

Data herein demonstrates durability and support for treatment of thoracic aortic disease with the GORE TAG conformable thoracic stent graft, including no incidents of stent compression/fracture and high freedom from aortic-related mortality. The planned analysis of follow-up to 10 years in GREAT will be beneficial.

Current perspectives in acute type B aortic dissections: a literature review

In this new millennial, endovascular strategies have revolutionized the treatment of acute type B aortic dissection (aTBAD). With reduced in-hospital mortality and good long-term outcomes TEVAR has become the gold standard for the treatment of complicated dissection and is gaining increasing support for its preventive applicability in some uncomplicated dissections. With this new paradigm came a shift of the treatment goal where just covering the entry tear is not enough and instead achieving long-term positive thoracoabdominal remodeling is needed. More extensive approaches with composite device designs (covered stent graft and bare metal stent) emerged to answer this aortic conundrum. At 5-year of follow-up, "Provisional ExTension To Induce COmplete Attachment technique" (PETTICOAT) and its evolution "Stent assisted balloon induced intimal disruption and relamination in aortic dissection repair" (STABILISE) seem to be safe techniques that can allow, when anatomically feasible, excellent aortic remodeling and, in some cases, even the healing of the dissection. Nevertheless, STABILISE results, although promising, are mostly based on small series and therefore need to be validated by analyzing medium-long-term results from the international registry. Given the plethora of new data and the disparity of expert opinions on the best treatment to adopt, in this review we aim to summarize the current knowledge on the results of these different strategies for acute TBAD.

Contemporary outcomes of open repair of acute complicated type B aortic dissection

OBJECTIVE

Open repair of acute complicated type B aortic dissection (ACTBAD), required when endovascular repair is not possible, is historically considered high-risk. We analyze our experience with this high-risk cohort compared with the standard cohort.

METHODS

We identified consecutive patients undergoing descending thoracic or thoracoabdominal aortic aneurysm (TAAA) repair from 1997 to 2021. Patients with ACTBAD were compared with those having surgery for other reasons. Logistic regression was used to identify associations with major adverse events (MAEs). Five-year survival and competing risk of reintervention were calculated.

RESULTS

Of 926 patients, 75 (8.1%) had ACTBAD. Indications included rupture (25/75), malperfusion (11/75), rapid expansion (26/75), recurrent pain (12/75), large aneurysm (5/75), and uncontrolled hypertension (1/75). The incidence of MAEs was similar (13.3% [10/75] vs 13.7% [117/851], P = .99). Operative mortality was 5.3% (4/75) vs 4.8% (41/851) (P = .99). Complications included tracheostomy (8%, 6/75), spinal cord ischemia (4%, 3/75), and new dialysis (2.7%, 2/75). Renal impairment, urgent/emergent operation, forced expiratory volume in 1 second ≤50%, and malperfusion were associated with MAEs, but not ACTBAD (odds ratio: 0.48, 95% confidence interval [CI]: [0.20-1.16], P = .1). At 5 and 10 years, there was no difference in survival (65.8% [95% CI: 54.6-79.2] vs 71.3% [95% CI: 67.9-74.9], P = .42, and 47.3% [95% CI: 34.5-64.7] vs 53.7% [95% CI: 49.3-58.4], P = .29, respectively) or 10-year reintervention (12.5% [95% CI: 4.3-25.3] vs 7.1% [95% CI: 4.7-10.1], P = .17, respectively).

CONCLUSIONS

In an experienced center, open repair of ACTBAD can be performed with low rates of operative mortality and morbidity. Outcomes similar to elective repair are achievable even in high-risk patients with ACTBAD. In patients unsuitable for endovascular repair, transfer to a high-volume center experienced in open repair should be considered.