Overview of aortic aneurysm management in the endovascular era

Differences in mortality and risk factors, two years after endovascular repair of ruptured abdominal aortic aneurysms - Reassessment analysis

OBJECTIVE

The prevalence of abdominal aortic aneurysms (AAA) increases with age. Elective intervention for AAA is critical to prevent rupture associated with very high mortality among older males.

METHODS

The aim of this study was to address the impact of post-contrast acute kidney-PC-AKI injury among patients treated with endovascular repair of ruptured AAA-EVAR on outcomes such as new onset chronic kidney disease-CKD and mortality among patients within a two-year trial.

RESULTS

The same study group (of n = 192 patients) underwent reassessment, two years after EVAR treatment. The overall mortality rate was 16.67%, and it was higher in the AKI group - 38.89%. CKD patients had a mortality rate of 23.88% (n = 16). Among patients with an aneurysm diameter >67 mm mortality rate reached 20% (n = 6), while in the previously reported diabetes mellitus group 37.93% (n = 11). New onset of CKD was diagnosed in 23% of cases. Preexisting CKD patients with PC- AKI contributed to a 33.33% mortality rate (n = 8).

CONCLUSION

This study concludes that PC-AKI impacts outcomes and survival in endovascularly treated AAAs. Type 2 diabetes and preexisting chronic kidney disease are associated with higher mortality within a 2-year follow-up, however gender factor was not significant. A larger aneurysm diameter is related with a higher prevalence of PC-AKI. These factors should be taken into account during screening, qualifying patients for the treatment and treating patients with AAA. It may help to identify high-risk individuals and tailor preventive measurements and treatment options accordingly, improving treatment results and reducing mortality.

The Role of Inflammasome in Abdominal Aortic Aneurysm and Its Potential Drugs

Abdominal aortic aneurysm (AAA) has been recognized as a serious chronic inflammatory degenerative aortic disease in recent years. At present, there is no other effective intervention except surgical treatment for AAA. With the aging of the human population, its incidence is increasing year by year, posing a serious threat to human health. Modern studies suggest that vascular chronic inflammatory response is the core process in AAA occurrence and development. Inflammasome, a multiprotein complex located in the cytoplasm, mediates the expression of various inflammatory cytokines like interleukin (IL)-1β and IL-18, and thus plays a pivotal role in inflammation regulation. Therefore, inflammasome may exert a crucial influence on the progression of AAA. This article reviews some mechanism studies to investigate the role of inflammasome in AAA and then summarizes several potential drugs targeting inflammasome for the treatment of AAA, aiming to provide new ideas for the clinical prevention and treatment of AAA beyond surgical methods.

Spectral computed tomography angiography using a gadolinium-based contrast agent for imaging of pathologies of the aorta

OBJECTIVES

Especially patients with aortic aneurysms and multiple computed tomography angiographies (CTA) might show medical conditions which oppose the use of iodine-based contrast agents. CTA using monoenergetic reconstructions from dual layer CT and gadolinium (Gd-)based contrast agents might be a feasible alternative in these patients. Therefore, the purpose of this study was to evaluate the feasibility of clinical spectral CTA with a Gd-based contrast agent in patients with aortic aneurysms.

METHODS

Twenty-one consecutive scans in 15 patients with and without endovascular aneurysm repair showing contraindications for iodine-based contrast agents were examined using clinical routine doses (0.2 mmol/kg) of Gd-based contrast agent with spectral CT. Monoenergetic reconstructions of the spectral data set were computed.

RESULTS

There was a significant increase in the intravascular attenuation of the aorta between pre- and post-contrast images for the MonoE40 images in the thoracic and the abdominal aorta (p < 0.001 for both). Additionally, the ratio between pre- and post-contrast images was significantly higher in the MonoE40 images as compared to the conventional images with a factor of 6.5 ± 4.5 vs. 2.4 ± 0.5 in the thoracic aorta (p = 0.003) and 4.1 ± 1.8 vs. 1.9 ± 0.5 in the abdominal aorta (p < 0.001).

CONCLUSIONS

To conclude, our study showed that Gd-CTA is a valid and reliable alternative for diagnostic imaging of the aorta for clinical applications. Monoenergetic reconstructions of computed tomography angiographies using gadolinium based contrast agents may be a useful alternative in patients with aortic aneurysms and contraindications for iodine based contrast agents.

Risk factors associated with surgical site infections in patients undergoing cardiothoracic surgery: A systematic review and meta-analysis

Surgical site infections (SSIs) following cardiothoracic surgery can pose significant challenges to patient recovery and outcome. This systematic review and meta-analysis aim to identify and quantify the risk factors associated with SSIs in patients undergoing cardiothoracic surgery. A comprehensive literature search adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and based on the PICO paradigm was conducted across four databases: PubMed, Embase, Web of Science and the Cochrane Library, without any temporal restrictions. The meta-analysis incorporated studies detailing the risk factors for post-operative sternal infections, especially those reporting odds ratios (OR) or relative risks with 95% confidence intervals (CI). Quality assessment of the studies was done using the Newcastle-Ottawa Scale. Statistical analysis was executed using the chi-square tests for inter-study heterogeneity, with further analyses depending on I2 values. Sensitivity analyses were performed, and potential publication bias was also assessed. An initial dataset of 2442 articles was refined to 21 articles after thorough evaluations based on inclusion and exclusion criteria. Patients with diabetes mellitus have an OR of 1.80 (95% CI: 1.40-2.20) for the incidence of SSIs, while obese patients demonstrate an OR of 1.63 (95% CI: 1.40-1.87). Individuals who undergo intraoperative blood transfusion present an OR of 1.13 (95% CI: 1.07-1.18), and smokers manifest an OR of 1.32 (95% CI: 1.03-1.60). These findings unequivocally indicate a pronounced association between these factors and an elevated risk of SSIs post-operatively. This meta-analysis confirms that diabetes, obesity, intraoperative transfusion and smoking heighten the risk of SSIs post-cardiac surgery. Clinicians should be alert to these factors to optimise patient outcomes.

Accuracy and Sterilizability of In-House Printed Patient-Specific Aortic Model for Surgeon-Modified Stent Grafts-A Workflow Description for Emergency Aortic Endovascular Procedures

Introduction: The use of 3D-printed aortic models for the creation of surgeon-modified endoprostheses represents a promising avenue in aortic surgery. By focusing on the potential impact of sterilization on model integrity and geometry, this report sheds light on the suitability of these models for creating customized endoprostheses. The study presented here aimed to investigate the safety and viability of 3D-printed aortic models in the context of sterilization processes and subsequent remodeling. Methods: The study involved the fabrication of 3D-printed aortic models using patient-specific imaging data and established additive manufacturing techniques. Five identical aortic models of the same patient were printed. Two models were subjected to sterilization and two to disinfection using commonly employed methods, and one model remained untreated. The models were checked by in-house quality control for deformation (heat map analyses) after the sterilization and disinfection processes. Three models (sterilized, disinfected, and untreated) were sent for ex-house (Lufthansa Technik, AG, Materials Technologies and Central Laboratory Services, Hamburg, Germany) evaluation and subsequent quantification of possible structural changes using advanced imaging and measurement technologies (macroscopic and SEM/EDX examinations). After sterilization and disinfection, each aortic model underwent sterility checks. Results: Based on macroscopic and SEM/EDX examinations, distinct evidence of material alterations attributed to a treatment process, such as a cleaning procedure, was not identified on the three implants. Comparative material analyses conducted via the EDX technique yield consistent results for all three implants. Disinfected and sterilized models tested negative for common pathogens. Conclusions: The evaluation of 3D-printed aortic models' safety after sterilization as well as their suitability for surgeon-modified endoprostheses is a critical step toward their clinical integration. By comprehensively assessing changes in model integrity and geometry after sterilization, this research has contributed to the broader understanding of the use of 3D-printed models for tailor-made endovascular solutions. As medical technologies continue to evolve, research endeavors such as this one can serve as a foundation for harnessing the full potential of 3D printing to advance patient-centered care in aortic surgery.

Ferrostatin-1 inhibits ferroptosis of vascular smooth muscle cells and alleviates abdominal aortic aneurysm formation through activating the SLC7A11/GPX4 axis

Ferroptosis, a type of iron-catalyzed necrosis, is responsible for vascular smooth muscle cell (VSMC) death and serves as a potential therapeutic target for alleviating aortic aneurysm. Here, our study explored the underlying mechanism of ferroptosis affecting VSMC functions and the resultant formation of AAA using its inhibitor Ferrostatin-1 (Fer-1). Microarray-based gene expression profiling was employed to identify differentially expressed genes related to AAA and ferroptosis. An AAA model was established by angiotensin II (Ang II) induction in apolipoprotein E-knockout (ApoE-/- ) mice, followed by injection of Fer-1 and RSL-3 (ferroptosis inducer). Then, the role of Fer-1 and RSL-3 in the ferroptosis of VSMCs and AAA formation was analyzed in Ang II-induced mice. Primary mouse VSMCs were cultured in vitro and treated with Ang II, Fer-1, sh-SLC7A11, or sh-GPX4 to assess the effect of Fer-1 via the SLC7A11/GPX axis. Bioinformatics analysis revealed that GPX4 was involved in the fibrosis formation of AAA, and there was an interaction between SLC7A11 and GPX4. In vitro assays showed that Fer-1 alleviated Ang II-induced ferroptosis of VSMCs and retard the consequent AAA formation. The mechanism was associated with activation of the SLC7A11/GPX4 pathway. Silencing of SLC7A11 or GPX4 could inhibit the ameliorating effect of Fer-1 on the ferroptosis of VSMCs. In vivo animal studies further demonstrated that Fer-1 inhibited Ang II-induced ferroptosis and vessel wall structural abnormalities in AAA mouse through activation of the SLC7A11/GPX4 pathway. Fer-1 may prevent AAA formation through activation of the SLC7A11/GPX4 pathway.

Acute periapical dental abscesses and increased risk for extracranial carotid artery aneurysms

Aim: To assess the prevalence of acute periapical abscesses (PAs) in patients with a history of extracranial carotid artery aneurysms (ECAA). Materials and methods: History of acute PAs and ECAA diagnosis was retrieved by searching the appropriate query in the database. All cases were diagnosed for acute PAs by calibrated dentists for patients admitted to urgent care. The odds ratio (OR) for the prevalence of acute PAs and its association with history of ECAA were then calculated. Results: The prevalence of acute PAs in patients with a history ECAA was significantly higher as compared to the general hospital patient population (p < 0.0001). The OR was 5.5. Females were more affected than males by 1.7 folds (p < 0.001). Whites were more affected than African Americans by 1.6 folds (p < 0.00001). Conclusions: The high prevalence of acute PAs in patients with a history of ECAA may suggest an association between these two conditions warranting a thorough medical examination.

Association Between Type of Anaesthesia and Clinical Outcome in Patients Undergoing Endovascular Repair of Thoraco-Abdominal Aortic Aneurysms by Fenestrated and Branched Endografts

OBJECTIVE

Although endovascular repair of thoraco-abdominal aortic aneurysm (TAAA) is the treatment of choice in the high risk population that is ineligible for an open surgical approach, little is known about the association between the type of anaesthesia and complications. This study compared the short term clinical outcomes of patients undergoing the visceral step of TAAA with fenestrated endograft aortic repair (FEVAR) and branched endograft aortic repair (BEVAR) under general anaesthesia (GA) with sedation with monitored care anaesthesia (MAC).

METHODS

This single centre, retrospective, observational study recruited 124 consecutive patients undergoing elective F/BEVAR from 2014 - 2021. The primary endpoint was the short term complication rate according to the type of anaesthesia. Secondary endpoints included: need for inotropes or vasopressors for hypotension, time spent in the operating room, and admission to the intensive care unit. Propensity score matching was generated to account for the between group imbalance in the pre-operative covariables.

RESULTS

After propensity score matching, 42 patients under GA were matched with 42 under MAC. The two groups showed no difference in cardiac and non-cardiac complications. Among the secondary outcomes, a higher number of patients in the GA group required inotropes or vasopressors compared with MAC (33% vs. 9%; p = .031). Although GA and MAC showed the same 30 day technical success (81% vs. 83%; p = .078), non-significant lower rates of major adverse events (10% vs. 12%; p = .72), one year re-intervention (14% vs. 21%; p = .39), and one year target vessel instability (10% vs. 21%; p = .39) were observed in the GA group. Overall, the in hospital mortality rate was 4%, with no difference between GA and MAC (2% vs. 5%; p = 1.0).

CONCLUSION

The type of anaesthesia seemed to have no effect on procedure success, peri-operative morbidity, or mortality in patients undergoing F/BEVAR.

Contrast-enhanced US Evaluation of Endoleaks after Endovascular Stent Repair of Abdominal Aortic Aneurysm

Ruptured abdominal aortic aneurysm (AAA) carries high morbidity and mortality. Elective repair of AAA with endovascular stent-grafts requires lifetime imaging surveillance for potential complications, most commonly endoleaks. Because endoleaks result in antegrade or retrograde systemic arterialized flow into the excluded aneurysm sac, patients are at risk for recurrent aneurysm sac growth with the potential to rupture. Multiphasic CT has been the main imaging modality for surveillance and symptom evaluation, but contrast-enhanced US (CEUS) offers a useful alternative that avoids radiation and iodinated contrast material. CEUS is at least equivalent to CT for detecting endoleak and may be more sensitive. The authors provide a general protocol and technical considerations needed to perform CEUS of the abdominal aorta after endovascular stent repair. When there are no complications, the stent-graft lumen has homogeneous enhancement, and no contrast material is present in the aneurysm sac outside the stented lumen. In patients with an antegrade endoleak, contrast material is seen simultaneously in the aneurysm sac and stent-graft lumen, while delayed enhancement in the sac is due to retrograde leak. Recognition of artifacts and other potential pitfalls for CEUS studies is important for examination performance and interpretation. Online supplemental material is available for this article. ^©RSNA, 2022.

Comparison of percutaneous and cutdown access‑related minor complications after endovascular aortic repair

The aim of the present study was to compare the open surgical and percutaneous access for thoracic/endovascular aortic repair (T/EVAR) regarding in-hospital and post-hospital minor-complications. Percutaneous (pEVAR) and cutdown (cEVAR) techniques for femoral vessel access for T/EVAR were compared regarding their minor complications. The basic population of this retrospective cohort study consisted of 44 percutaneous and 215 cutdown accesses for endovascular aortic repair (T/EVAR-procedure) conducted between August 2008 and October 2019. The primary outcome consisted of conservatively treatable minor complications until hospital discharge and during follow up. Secondary outcomes comprised postoperative pain and complications requiring invasive treatment. Minor complications were observed in 11.4% (pEVAR) vs. 9% (cEVAR) of cases throughout index hospital stay and 10 vs. 13.7% during follow-up. No significant differences were noticed regarding overall complication rate between pEVAR and cEVAR. Only bleedings treatable through compression occurred significantly more often in the pEVAR-group (6.8 vs. 0.5%; P=0.02). In conclusions, the percutaneous technique represents a safe and quickly executable alternative to cutdown access. A significant difference in overall minor complications could not be observed. In both techniques, complications may occur even months after surgery. In order to demonstrate the superiority of the percutaneous technique compared with cutdown access, possible predictors for the use of the percutaneous technique should be defined in the future.

Platelet TGF-β1 inhibits the migration and proliferation of smooth muscle cells in aneurysms

BACKGROUND

The study explored the role of platelet TGF-β1 from the perspective of inhibiting the excessive proliferation, migration and invasion of murine aortic vascular smooth muscle cells (MASMCs).

METHOD

The platelets were first extracted from C57BL/6 mice, and the TGF-β1 protein was obtained after the purification of protein. In vitro, the concentrations of angiotensin Ⅱ (Ang Ⅱ) and TGF-β1 for intervention were screened by testing the viability of MASMCs, followed by the analysis concerning the effects of platelets, Ang Ⅱ and TGF-β1 on the proliferation, migration, invasion, and the expressions of pathway-related proteins in MASMCs. In vivo, an Ang Ⅱ-induced mouse model was established. TGF-β1 was injected into the tail of mice as a therapeutic agent, and its action mechanism was further verified by the treatment of inhibitor SB505124. The results of the cell experiment were validated by evaluating the maximum diameter of abdominal aorta, the proportion of total weight, the changes of both pathology and the expressions of pathway-related proteins in the mice.

RESULT

0.5 ng/mL Ang Ⅱ and 15 ng/mL TGF-β1 were chosen for treatment. The following results of cell functional experiments and Western blot assay demonstrated that Ang Ⅱ promoted the proliferation, migration and invasion of MASMCs via regulating related pathways, the effects of which were evidently reversed by TGF-β1 and platelets. Consistent results were also observed in the animal experiments, where TGF-β1 effectively alleviated Ang Ⅱ-induced abdominal aortic injury in mice.

CONCLUSION

TGF-β1 in platelets inhibits Ang Ⅱ-induced proliferation, migration and invasion of MASMCs.

Comprehensive comparison of three different workstations for accurate planning of endovascular stent implantation in patients with thoracic aortic aneurysms

Purpose

To assess the diagnostic precision of three different workstations for measuring thoracic aortic aneurysms (TAAs) in vivo and ex vivo using either pre-interventional computed tomography angiography scans (CTA) or a specifically designed phantom model.

Methods

This retrospective study included 23 patients with confirmed TAA on routinely performed CTAs. In addition to phantom tube diameters, one experienced blinded radiologist evaluated the dimensions of TAAs on three different workstations in two separate rounds. Precision was assessed by calculating measurement errors. In addition, correlation analysis was performed using Pearson correlation.

Results

Measurements acquired at the Siemens workstation deviated by 3.54% (range, 2.78–4.03%; p = 0.14) from the true size, those at General Electric by 4.05% (range, 1.46–7.09%; p < 0.0001), and at TeraRecon by 4.86% (range, 3.22–6.45%; p < 0.0001). Accordingly, Siemens provided the most precise workstation at simultaneously most fluctuating values (scattering of 4.46%). TeraRecon had the smallest fluctuation (scattering of 2.83%), but the largest deviation from the true size of the phantom. The workstation from General Electric showed a scattering of 2.94%. The highest overall correlation between the 1st and 2nd rounds was observed with measurements from Siemens (r = 0.898), followed by TeraRecon (r = 0.799), and General Electric (r = 0.703). Repetition of measurements reduced processing times by 40% when using General Electric, by 20% with Siemens, and by 18% with TeraRecon.

Conclusions

In conclusion, all three workstations facilitated precise assessment of dimensions in the majority of cases at simultaneously high reproducibility, ensuring accurate pre-interventional planning of thoracic endovascular aortic repair.

•

Pre-interventional planning of TEVAR in patients with TAAs using CTA is feasible.

•

All three workstations facilitated accurate measurements in vivo and ex vivo.

•

Repetition of measurements resulted in faster processing due to learning effects.

Akkermansia muciniphila Alters Gut Microbiota and Immune System to Improve Cardiovascular Diseases in Murine Model

The gut microbiota plays an important role in a variety of cardiovascular diseases. The probiotics screened based on microbiota can effectively improve metabolism and immune function of the body, which is of great value in the field of cardiovascular disease treatment. Abdominal aortic aneurysms (AAA) refer to the lesion or injury of the abdominal aortic wall resulting in a localized bulge, which is one of the cardiovascular diseases with pulsing mass as the main clinical symptom. Previous studies have confirmed that A. muciniphila was depleted in the guts of AAA patients or mice. A. muciniphila is a potential probiotic for the treatment of intestinal microbiome-related diseases. Therefore, this study aims to investigate the effects of A. muciniphila on gut microbiota and disease-related biomarkers in AAA mice. C57BL/6J mice were used to construct the AAA model and treated with A. muciniphila. Aortic aneurysm formation in the AAA group is associated with the increased diameter of the abdominal aorta and inflammatory infiltration. A. muciniphila inhibited the formation of AAA and repaired tissue damage. The number of gut microbiota and α diversity index were decreased in the model group. A. muciniphila increased the number of gut microbiota and α diversity in AAA mice. The abundance of uncultured bacterium and Lactobacillus were increased, while the abundance of the Lachnospiraceae NK4A136 group was reduced in the AAA group. Compared with the control group, the levels of MMP-1, MMP-9, IL-33, CTSB, and CTSL in tissue and the levels of IL-6, IFN-γ, and CRP in blood were significantly increased, and the levels of IL-4, IL-10, and IL-17A in blood were significantly decreased in the AAA group. The intervention of A. muciniphila reversed these changes. The gut microbiota function prediction showed changes in E. coli, Clostridium, and Lactobacillus metabolism-related functional pathways. Akkermansia was negatively correlated with Helicobacter and Lactobacillus and positively correlated with Clostridium_sensu_stricto_1 and Escherichia shigella at the genus level. In conclusion, A. muciniphila inhibited the formation of AAA by restoring gut microbiota diversity, altering the expression of peripheral immune factors, and the functions of E. coli, Clostridium, and Lactobacillus, which may provide a new theoretical basis for the application of probiotics in cardiovascular diseases.

Comparison of Surgical Outcomes of Laparoscopic Glue and Laparoscopic Suture Hernioplasty in Pediatric Female Inguinal Hernia

This study aimed to report the surgical outcomes of laparoscopic glue hernioplasty (LGH) compared with conventional laparoscopic suture hernioplasty (LSH) in pediatric female inguinal hernia repair. We retrospectively analyzed 465 female pediatric patients who underwent laparoscopic inguinal hernia repair between January 2013 and December 2020. LGH and LSH were performed in 95 and 370 cases, respectively. Surgical outcomes (length of hospital stay, operative time, complications, and recurrences) were compared between the LGH and LSH groups. We found that the operation times for bilateral hernia repair were shorter in the LGH group (LGH: 35.5 ± 8.2 min, LSH: 45.2 ± 11.6 min; p < 0.001). No significant differences in complications or recurrences were observed between the two groups during the follow-up period. Our findings suggest that LGH is a feasible and easily applied surgical technique for the treatment of pediatric female inguinal hernia.

New paradigms in minimally-invasive vascular surgery

INTRODUCTION

Vascular surgery has been greatly evolved during the last decades and novel minimally invasive techniques have been introduced. Aim of this review is to briefly present all these advances and compare them with traditional repairs.

AREAS COVERED

The authors have extensively searched literature through the Pubmed and Embase databases. All articles published up to December 2021 referring to minimally invasive techniques used for treatment of peripheral artery disease, carotid disease, aortic aneurysms and venous disease were evaluated. Minimally invasive techniques under investigation included endovascular and hybrid techniques, robot-assisted and laparoscopic approaches.

EXPERT OPINION

Several minimally invasive techniques such as endovascular and hybrid approaches have been extensively used during the last two decades to treat vascular surgery patients offering them lower mortality and morbidity risks. Novel robot assisted techniques have shown promising results in preclinical studies although further clinical evaluation is needed.

A ruptured mycotic aortic aneurysm in a patient with urinary retention: A case report

Symptomatic abdominal aortic aneurysm (AAA) is a diagnosis that is a true emergency. Since AAAs are typically asymptomatic prior to rupturing, they can easily be missed. When an abdominal aortic aneurysm becomes symptomatic and ruptures, the ramifications can be catastrophic for the patient. We present a case of a 55-year-old male who presented with urinary retention and suprapubic pain. Computerized tomography demonstrated a rapidly expanding AAA and signs of impending rupture. Emergent vascular surgical repair was performed successfully. There was concern for mycotic nature of the AAA with recent COVID-19 infection and possible bacteremia. This case demonstrates the need for maintaining a wider differential when examining patients and avoiding anchoring bias and serves as a point of discussion for potential complications of COVID-19 infection.

Huge Thoracic Aortic Aneurysm Presenting with Jaundice: A Case Report

Introduction

Thoracic aortic aneurysms (TAA) are encountered frequently in the emergency department with an obscure presentation. Most of these aneurysms are incidentally discovered while doing routine imaging studies. This report describes a case of unusual presentation of TAAs.

Case Presentation

A 37-year-old male presented to the emergency department with jaundice, shortness of breath, abdominal swelling, and lower limb edema, which worsened during the previous month. The patient was worked up and diagnosed with an ascending aortic aneurysm measuring 6.9 cm associated with severe aortic insufficiency and heart failure.

Conclusion

TAA is a life-threatening condition with indistinct signs and symptoms. A high index of suspicion and early implementation of radiological studies are prerequisites to reach a diagnosis.

Inaccurate Risk Assessment by the ACS NSQIP Risk Calculator in Aortic Surgery

OBJECTIVES

The aim of this retrospective study was to assess the predictive performance of the American College of Surgeons (ACS) risk calculator for aortic aneurysm repair for the patient population of a Dutch tertiary referral hospital.

METHODS

This retrospective study included all patients who underwent elective endovascular or open aortic aneurysm repair at our institution between the years 2013 and 2019. Preoperative patient demographics and postoperative complication data were collected, and individual risk assessments were generated using five different current procedural terminology (CPT) codes. Receiver operating characteristic (ROC) curves, calibration plots, Brier scores, and Index of Prediction Accuracy (IPA) values were generated to evaluate the predictive performance of the ACS risk calculator in terms of discrimination and calibration.

RESULTS

Two hundred thirty-four patients who underwent elective endovascular or open aortic aneurysm repair were identified. Only five out of thirteen risk predictions were found to be sufficiently discriminative. Furthermore, the ACS risk calculator showed a structurally insufficient calibration. Most Brier scores were close to 0; however, comparison to a null model though IPA-scores showed the predictions generated by the ACS risk calculator to be inaccurate. Overall, the ACS risk calculator showed a consistent underestimation of the risk of complications.

CONCLUSIONS

The ACS risk calculator proved to be inaccurate within the framework of endovascular and open aortic aneurysm repair in our medical center. To minimize the effects of patient selection and cultural differences, multicenter collaboration is necessary to assess the performance of the ACS risk calculator in aortic surgery.

Endovascular repair of abdominal aortic or iliac artery pathologies in patients with autosomal dominant polycystic kidney disease

BACKGROUND

This study aims to evaluate the efficacy and safety of endovascular aneurysm repair (EVAR) of abdominal aortic or iliac artery pathologies in patients with autosomal dominant polycystic kidney disease (ADPKD).

METHODS

From January 2014 to December 2019, fifteen consecutive patients (13 men, mean age 69.3 years, range 56-82 years) with abdominal aortic or iliac artery pathologies coexisting with ADPKD underwent EVAR in our department. Their general data, perioperative results and follow-up outcomes were retrospectively reviewed and analyzed. RESULTS：Among the fifteen patients, eleven had abdominal aortic aneurysms, one had isolated abdominal aortic dissection and the other three had iliac artery aneurysms. Three patients had thoracic penetrating aortic ulcer and two had intracranial aneurysms as the comorbidities. All patients underwent EVAR with the aorto-iliac pathologies successfully excluded. The average operative time was 171±73 minutes and average contrast volume was 87±12mL. The average follow-up time was 38.4 months (range 6-60). Aorta-bi-iliac stent-grafts were deployed in fourteen patients, while one patient received tubular stent-graft. Two patients underwent simultaneous TEVAR and EVAR, and One underwent EVAR 3 months after TEVAR. One patient was found to have a hematoma at the site of femoral access 3 days after EVAR. One patient was found to have a Type Ib endoleak 5 months after EVAR, and he recovered well with a secondary endovascular intervention. Contrast-induced nephropathy was observed in two patients (13%) post EVAR. Another patient developed renal failure 20 months after EVAR, and was treated with regular hemodialysis. All other patients did not have any reported significant deterioration of renal function during follow-up. No other adverse events, such as death, paraplegia, aneurysm rupture, or open surgery conversion occurred during operation and follow-up.

CONCLUSIONS

For patients with abdominal aortic or iliac artery diseases coexisting with ADPKD, EVAR had satisfactory mid-term outcomes, without significantly exacerbating the decline of renal function. However, patients with ADPKD might have multiple vascular lesions, especially intracranial aneurysms, which should be paid enough attention in clinical practice.

Outcomes of Endovascular Aneurysm Repair with Adjunctive Stenting

OBJECTIVE

Endovascular aneurysm repair is the standard of care for abdominal aortic aneurysm repair, however data regarding adjunctive stenting at the time of endovascular aneurysm repair (EVAR) are limited. The study aims to evaluate outcomes of patients undergoing EVAR with and without adjunctive stenting.

METHODS

Patients undergoing EVAR with stenting (EVAR-S) and without stenting (EVAR) (2008 to 2017) were selected from Cerner HealthFacts® database using ICD-9 diagnosis and procedure codes. Chi-square analysis and multivariable logistic regression were used to evaluate the association of patient characteristics with medical and vascular outcomes.

RESULTS

4,957 patients undergoing EVAR procedures were identified (3,816 EVAR and 1,141 EVAR-S). Demographic analysis revealed that patients who underwent EVAR-S had higher Charlson comorbidity scores (2.35 vs. 2.13, p = .0001). EVAR-S was associated with a greater frequency of vascular complications such as thrombolysis/percutaneous thrombectomy (0.9% vs. 0.2%; p < .0004). There were no differences seen in access complications between EVAR and EVAR-S. Multivariable analysis revealed that EVAR-S was associated with prolonged length of stay (OR 1.37, 95% CI 1.03-1.82), readmission < 30 days (OR 1.36, 95% CI 1.11-1.68), major adverse cardiac events (OR 1.59, 95% CI 1.09-2.32), respiratory complications (OR 1.47, 95% CI 1.16-1.88) and renal failure (OR 1.57, 95% CI 1.16-2.11).

CONCLUSIONS

Endovascular aneurysm repair with adjunctive stenting (EVAR-S) was associated with vascular complications requiring reintervention, although the overall rate was very low. As well, readmission within 30 days, cardiac complications, respiratory problems and renal failure were more likely when compared to standard EVAR. The need for adjunctive stenting acts as a marker for an overall sicker and more complex population, not just in terms of vascular complications but across all medical complications as well. Staging the procedure may be helpful in terms of spreading out the operative risk into smaller portions. Furthermore, consideration of a non-operative strategy should be discussed with the patient if the risk of the procedure outweighs the risk of aneurysm rupture in high-risk groups.

WITHDRAWN: Circ-LAMP2 regulates aortic smooth muscle cell proliferation and apoptosis in thoracic aortic aneurysm via modulation of autophagy and NF-κB pathway

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NEAT1 boosts the development of thoracic 1 aortic aneurysm through targeting miR-324-5p/RAN

BACKGROUND

Long non-coding RNAs (lncRNAs) have been identified in multiple cancers. Recently, NEAT1 is found to be up regulated in cervical cancer. Since the relationship between NEAT1 and thoracic aortic aneurysm (TAA) has not been clarified, our study focused on the role of NEAT1 in TAA.

METHODS

Bioinformatics, RNA pulls down and luciferase reporter assay were used to discover and determine miR-324-5p to be a target of NEAT1. RT-qPCR was used to examine NEAT1, RAN and miR-324-5p expression.

RESULTS

NEAT1 was up-regulated in TAA patients, as well as HAoSMC and HA-VSMC cells. Down-regulation of NEAT1 could inhibit the proliferative abilities while promoting apoptosis of TAA cells. MiR-324-5p expression was down-regulated in both TAA tissues and cells. Then, RAN was selected out as a target of miR-324-5p. More interestingly, miR-324-5p had inhibitory effects on malignant behaviors of TAA cells. RAN was negatively related with miR-324-5p while positively correlated with NEAT1 in the tissues. Finally, the data of rescue assays manifested that RAN up-regulation could countervail the influence of down-regulation of NEAT1 on TAA cells.

CONCLUSION

NEAT1 could contribute to the malignant behaviors of TAA cells by targeting miR-324-5p/RAN. NEAT1 might be an underlying target for the therapy of TAA.

Aortic aneurysms and dissections: Unmet needs from physicians and engineers perspectives

The treatment of aortic disease is complex, requiring cardiothoracic and vascular surgeons to make pre-, post- and intraoperative decisions directly influencing patient survival and well-being. Despite tremendous advancement in vascular surgery and endovascular techniques in the last two decades, along with the abundance of research in the field, many unmet needs and unanswered questions remain. Tight collaboration between engineers and physicians is a keystone in translating new tools, techniques, and devices into practice. Here, we have gathered our perspective, as physicians and engineers, in several pressing issues associated with the diagnosis and treatment of aortic aneurysms and dissection, referring to the current knowledge and practice, signifying unmet needs as well as future directions.

Risk assessment in aortic aneurysm repair by medical specialists versus the American College of Surgeons National Surgical Quality Improvement Program risk calculator outcomes

Objective

The aim of this online clinical vignette-based survey study was to compare risk assessments by vascular surgeons, anaesthesiologists and interventional radiologists involved in treating patients with aortic aneurysms in the Netherlands with the NSQIP risk calculator outcomes.

Methods

Participants, recruited using purposive sampling, provided their estimation of the likelihood of postoperative complications and events following aortic surgery in five fictional cases. These cases were subsequently scored using the NSQIP calculator. The risk assessments were statistically analysed using the ANOVA and student t-test.

Results

All participating specialists i.e. twelve vascular surgeons, ten interventional radiologists and ten anaesthesiologists completed the survey. In the vast majority of outcomes and vignettes, no significant differences were found between various specialists, whereas significant differences were found between the NSQIP risk calculator outcomes and the combined risk assessments of the specialists. Overall, specialist risk assessments differ from the NSQIP, but neither particularly higher nor lower compared to the risk calculator.

Conclusions

Risk assessment by vascular surgeons, anaesthesiologists and interventional radiologists differs significantly with NSQIP risk calculator outcomes, within the framework of both endovascular and open aortic aneurysm repair. Based on these results, implementing the NSQIP risk calculator in preoperative workup could be of added value in both patient planning as well as adequately informing patients for obtaining consent.

Utility of 3D printed abdominal aortic aneurysm phantoms: a systematic review

BACKGROUND

3D printed (3DP) abdominal aortic aneurysm (AAA) phantoms are emerging in the literature as an adjunct for the visualization of complex anatomy, particularly for presurgical device selection and simulation. This is the first systematic review to provide a comprehensive overview of 3DP for endovascular aneurysm repair (EVAR) planning and intervention, evaluating the readiness of current levels of technology for mainstream implementation.

METHODS

A systematic literature search of PubMed and MEDLINE was performed as per PRISMA guidelines using the terms '3D Printing', 'AAA' OR 'EVAR' and related index terms, and further relevant articles were appraised via a snowballing approach. Our last search was conducted on 14 November 2020.

RESULTS

Twenty-five articles were identified for critical analysis, with 14 cases or technical reports. Nineteen publications utilized 3DP AAA phantoms to aid presurgical decision making, device selection and design. Four publications explored the utility of 3DP phantoms as EVAR trainers, and one publication examined the technology as a tool for patient education. Flexible, transparent phantoms were deemed most useful; however, the cost and availability of higher end machines limited accessibility.

CONCLUSION

3DP phantoms have been used in EVAR to facilitate visualization of complex patient anatomy, appropriate device selection, in predicting navigational difficulties and the shape and position of endograft after deployment. These phantoms show promise in reducing known complications such as endoleak, stent graft occlusion and migration; however, larger scale prospective studies are required to validate its impacts on patient outcomes and cost savings to the healthcare system.

Thoracic and abdominal aortic aneurysms: exploring their contrast and genetic associations

Until recently thoracic aortic aneurysm (TAA) and abdominal aortic aneurysm (AAA) were correlated with atherosclerosis but following a range of cohort studies, a linkage proved unlikely. Instead, data from the Genome wide association study detected two common significantly correlated lncRNA loci: miRNA and the antisense non-coding RNA in the INK4 locus (ANRIL). lncRNAs are sometimes utilized by the body as transcription regulators and signaling molecules. This is crucial in cell transformation and embryology, including that of the mammalian heart. ANRIL, a 19 exon RNA sequence found in the chromosome 9p21 region, will be one of the main focuses of this paper. TAA and AAA have many differences due to their vessel walls but similarities in their gross anatomic structure prove a genetic correlated disease likely. ANRIL has a convincing potential to be used as an additive therapeutic tool in TAA and AAA. This is because Chr9p21 is independent of typical risk factors. However, it remains that further research and clinical studies are required before clinical translation. It is best to consider TAA and AAA separately as the underlying pathophysiology has some distinct differences. They are both commonly diagnosed late, and the hope is that genetic mutations (ANRIL) can act as a biomarker for a faster diagnosis, management and possible treatment alternative.

Accessing 3D Printed Vascular Phantoms for Procedural Simulation

Introduction: 3D printed patient-specific vascular phantoms provide superior anatomical insights for simulating complex endovascular procedures. Currently, lack of exposure to the technology poses a barrier for adoption. We offer an accessible, low-cost guide to producing vascular anatomical models using routine CT angiography, open source software packages and a variety of 3D printing technologies.

Methods: Although applicable to all vascular territories, we illustrate our methodology using Abdominal Aortic Aneurysms (AAAs) due to the strong interest in this area. CT aortograms acquired as part of routine care were converted to representative patient-specific 3D models, and then printed using a variety of 3D printing technologies to assess their material suitability as aortic phantoms. Depending on the technology, phantoms cost $20–$1,000 and were produced in 12–48 h. This technique was used to generate hollow 3D printed thoracoabdominal aortas visible under fluoroscopy.

Results: 3D printed AAA phantoms were a valuable addition to standard CT angiogram reconstructions in the simulation of complex cases, such as short or very angulated necks, or for positioning fenestrations in juxtarenal aneurysms. Hollow flexible models were particularly useful for device selection and in planning of fenestrated EVAR. In addition, these models have demonstrated utility other settings, such as patient education and engagement, and trainee and anatomical education. Further study is required to establish a material with optimal cost, haptic and fluoroscopic fidelity.

Conclusion: We share our experiences and methodology for developing inexpensive 3D printed vascular phantoms which despite material limitations, successfully mimic the procedural challenges encountered during live endovascular surgery. As the technology continues to improve, 3D printed vascular phantoms have the potential to disrupt how endovascular procedures are planned and taught.

Bioinformatics analysis of common key genes and pathways of intracranial, abdominal, and thoracic aneurysms

Background

Aneurysm is a severe and fatal disease. This study aims to comprehensively identify the highly conservative co-expression modules and hub genes in the abdominal aortic aneurysm (AAA), thoracic aortic aneurysm (TAA) and intracranial aneurysm (ICA) and facilitate the discovery of pathogenesis for aneurysm.

Methods

GSE57691, GSE122897, and GSE5180 microarray datasets were downloaded from the Gene Expression Omnibus database. We selected highly conservative modules using weighted gene co‑expression network analysis before performing the Gene Ontology, Kyoto Encyclopedia of Genes and Genomes pathway and Reactome enrichment analysis. The protein–protein interaction (PPI) network and the miRNA-hub genes network were constructed. Furtherly, we validated the preservation of hub genes in three other datasets.

Results

Two modules with 193 genes and 159 genes were identified as well preserved in AAA, TAA, and ICA. The enrichment analysis identified that these genes were involved in several biological processes such as positive regulation of cytosolic calcium ion concentration, hemostasis, and regulation of secretion by cells. Ten highly connected PPI networks were constructed, and 55 hub genes were identified. In the miRNA-hub genes network, CCR7 was the most connected gene, followed by TNF and CXCR4. The most connected miRNAs were hsa-mir-26b-5p and hsa-mir-335-5p. The hub gene module was proved to be preserved in all three datasets.

Conclusions

Our study highlighted and validated two highly conservative co-expression modules and miRNA-hub genes network in three kinds of aneurysms, which may promote understanding of the aneurysm and provide potential therapeutic targets and biomarkers of aneurysm.

Therapeutic Potential of Heme Oxygenase-1 in Aneurysmal Diseases

Abdominal aortic aneurysm (AAA) and intracranial aneurysm (IA) are serious arterial diseases in the aorta and brain, respectively. AAA and IA are associated with old age in males and females, respectively, and if rupture occurs, they carry high morbidity and mortality. Aneurysmal subarachnoid hemorrhage (SAH) due to IA rupture has a high rate of complication and fatality. Despite these severe clinical outcomes, preventing or treating these devastating diseases remains an unmet medical need. Inflammation and oxidative stress are shared pathologies of these vascular diseases. Therefore, therapeutic strategies have focused on reducing inflammation and reactive oxygen species levels. Interestingly, in response to cellular stress, the inducible heme oxygenase-1 (HO-1) is highly upregulated and protects against tissue injury. HO-1 degrades the prooxidant heme and generates molecules with antioxidative and anti-inflammatory properties, resulting in decreased oxidative stress and inflammation. Therefore, increasing HO-1 activity is an attractive option for therapy. Several HO-1 inducers have been identified and tested in animal models for preventing or alleviating AAA, IA, and SAH. However, clinical trials have shown conflicting results. Further research and the development of highly selective HO-1 regulators may be needed to prevent the initiation and progression of AAA, IA, or SAH.

Internal iliac artery revascularisation versus internal iliac artery occlusion for endovascular treatment of aorto-iliac aneurysms

BACKGROUND

Endovascular aortic aneurysm repair (EVAR) is used to treat aorto-iliac and isolated iliac aneurysms in selected patients, and prospective studies have shown advantages compared with open surgical repair, mainly in the first years of follow-up. Although this technique produces good results, anatomic issues (such as common iliac artery ectasia or an aneurysm that involves the iliac bifurcation) can make EVAR more complex and challenging and can lead to an inadequate distal seal zone for the stent-graft. Inadequate distal fixation in the common iliac arteries can lead to a type Ib endoleak. To avoid this complication, one of the most commonly used techniques is unilateral or bilateral internal iliac artery occlusion and extension of the iliac limb stent-graft to the external iliac arteries with or without embolisation of the internal iliac artery. However, this occlusion is not without harm and is associated with ischaemic complications in the pelvic territory such as buttock claudication, sexual dysfunction, ischaemic colitis, gluteal necrosis, and spinal cord injury. New endovascular devices and alternative techniques such as iliac branch devices and the sandwich technique have been described to maintain pelvic perfusion and decrease complications, achieving revascularisation of the internal iliac arteries in patients not suitable for an adequate seal zone in the common iliac arteries. These approaches may also preserve the quality of life of treated individuals and may decrease other serious complications including spinal cord ischaemia, ischaemic colitis, and gluteal necrosis, thereby decreasing the morbidity and mortality of EVAR.

OBJECTIVES

To assess the effects of internal iliac artery revascularisation versus internal iliac artery occlusion during endovascular repair of aorto-iliac aneurysms and isolated iliac aneurysms involving the iliac bifurcation.

SEARCH METHODS

The Cochrane Vascular Information Specialists searched the Cochrane Vascular Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL), in the Cochrane Library; MEDLINE; Embase; the Cumulative Index to Nursing and Allied Health Literature (CINAHL); and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 28 August 2019. The review authors searched Latin American Caribbean Health Sciences Literature (LILACS) and the Indice Bibliográfico Español de Ciencias de la Salud (IBECS) on 28 August 2019 and contacted specialists in the field and manufacturers to identify relevant studies.

SELECTION CRITERIA

We planned to include all randomised controlled trials (RCTs) that compared internal iliac artery revascularisation with internal iliac artery occlusion for patients undergoing endovascular treatment of aorto-iliac aneurysms and isolated iliac aneurysms involving the iliac bifurcation.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed identified studies for potential inclusion in the review. We used standard methodological procedures in accordance with the Cochrane Handbook for Systematic Review of Interventions.

MAIN RESULTS

We identified no RCTs that met the inclusion criteria.

AUTHORS' CONCLUSIONS

We found no RCTs that compared internal iliac artery revascularisation versus internal iliac artery occlusion for endovascular treatment of aorto-iliac aneurysms and isolated iliac aneurysms involving the iliac bifurcation. High-quality studies that evaluate the best strategy for managing endovascular repair of aorto-iliac aneurysms with inadequate distal seal zones in the common iliac artery are needed.

WITHDRAWN: Revisions to the ICD-10-CM Code Set for Aortic Aneurysms and Dissection Can Advance Clinical Research, Outcomes Reporting, and High-Value Health Care Delivery

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Abdominal Aortic Aneurysm: A Case Report and Literature Review

INTRODUCTION

Abdominal aortic aneurysms (AAA) more commonly affect men than women and are estimated to affect 4% to 8% of men older that age 60 years. Mortality because of a ruptured AAA is high, but elective repair is an effective and relatively safe intervention.

CASE PRESENTATION

A 79-year-old man came to the Emergency Department because of worsening back pain. Workup revealed a previously unknown, 10-cm aneurysm that had ruptured. Unfortunately, the patient died during emergency surgery.

DISCUSSION

A literature review of proper screening, referral timeframe, the most common surgical techniques, potential complications, and postoperative surveillance was conducted. Early detection, referral to vascular surgery, and possible open or endovascular repair are key to limiting the morbidity and mortality associated with AAA.

microRNAs in bicuspid aortic valve associated aortopathy: Recent advances and future perspectives

The risk of acute aortic events in patients with bicuspid aortic valve (BAV) constitutes a medical concern in terms of timing and surgical decision. During the past years, there has been a growing interest in the potential of microRNAs (miRNAs) as crucial epigenetic factors in multiple cellular processes associated with BAV aortopathy. Nevertheless, there are still challenges that need to be overcome before miRNAs could enter clinical practice, and further validation studies in larger and well-defined BAV cohorts are now required. This review aims at providing a comprehensive overview of the available data on the expression profiles and function of specific miRNAs in BAV aortopathy, evaluating miRNA signatures as potential molecular markers of disease. We also discuss the role of other novel classes of non-coding RNAs, including long non-coding RNAs and circular RNAs, in BAV-associated aortopathy, mainly regarding their possible implementation as diagnostic and prognostic markers.

Histologic Analysis with the Newly Designed Exoskeleton Seal® Stent-Graft in the Porcine Abdominal Aorta

PURPOSE

To investigate the technical feasibility of a novel exoskeleton Seal^® stent-graft and analyze early histologic changes in the porcine abdominal aorta.

MATERIALS AND METHODS

Six pigs received an abdominal stent-graft (Group I), and six received an iliac branch stent-graft (Group II). Groups were subdivided as follows: Group Ia, which received three bifurcated main-body stent-grafts; Group Ib, which received three bifurcated main-body stent-grafts with both iliac graft-stents; Group IIa, which received three simple uni-iliac tapered stent-grafts; and Group IIb, which received three uni-iliac tapered tapered stent-grafts with right straight limb and left branched limb. Statistical analyses were performed with the Wilcoxon signed-rank test and mixed-model regression analysis.

RESULTS

The primary technical success rate (< 24 h) was 83% because of two acute thromboses in the lumen of the stented abdominal aorta immediately after stent-graft placement. At 4 weeks, late thrombosis occurred in two pigs. Higher mean neointimal hyperplasia areas (23.5% vs. 16.2%; P = .047), neointimal hyperplasia thicknesses (545.5 μm vs. 422.2 μm; P = .001), and degrees of collagen deposition (2.71 vs. 2.33; P = .002) were observed at the bare-metal stent-graft compared with the proximal exoskeleton portion of the stent-graft, with no significant differences between the patent and occluded groups or among the four types of stent-grafts.

CONCLUSIONS

The exoskeleton stent-graft demonstrates 66% of patency rate during 1-month follow-up due to four cases of thromboses; however, the endothelialization on the junction of proximal graft showed no significant differences between the patent and occluded groups. Further studies should investigate long-term outcomes with prolonged neointimal hyperplasia.

Berberine in Cardiovascular and Metabolic Diseases: From Mechanisms to Therapeutics

Cardiovascular and metabolic diseases (CVMD) are the leading causes of death worldwide, underscoring the urgent necessity to develop new pharmacotherapies. Berberine (BBR) is an eminent component of traditional Chinese and Ayurvedic medicine for more than 2000 years. Recently, BBR has attracted much interest for its pharmacological actions in treating and/or managing CVMD. Recent discoveries of basic, translational and clinical studies have identified many novel molecular targets of BBR (such as AMPK, SIRT1, LDLR, PCSK9, and PTP1B) and provided novel evidences supporting the promising therapeutic potential of BBR to combat CVMD. Thus, this review provides a timely overview of the pharmacological properties and therapeutic application of BBR in CVMD, and underlines recent pharmacological advances which validate BBR as a promising lead drug against CVMD.

Crossing Bridges between Extra- and Intra-Cellular Events in Thoracic Aortic Aneurysms

Thoracic aortic aneurysms (TAAs) are common, life-threatening diseases and are a major cause of mortality and morbidity. Over the past decade, genetic approaches have revealed that 1) activation of the transforming growth factor beta (TGF-β) signaling, 2) alterations in the contractile apparatus of vascular smooth muscle cells (SMCs), and 3) defects in the extracellular matrix (ECM) were responsible for development of TAAs. Most recently, a fourth mechanism has been proposed in that dysfunction of mechanosensing in the aortic wall in response to hemodynamic stress may be a key driver of TAAs. Interestingly, the elastin-contractile unit, which is an anatomical and functional unit connecting extracellular elastic laminae to the intracellular SMC contractile filaments, via cell surface receptors, has been shown to play a critical role in the mechanosensing of SMCs, and many genes identified in TAAs encode for proteins along this continuum. However, it is still debated whether these four pathways converge into a common pathway. Currently, an effective therapeutic strategy based on the underlying mechanism of each type of TAAs has not been established. In this review, we will update the present knowledge on the molecular mechanism of TAAs with a focus on the signaling pathways potentially involved in the initiation of TAAs. Finally, we will evaluate current therapeutic strategies for TAAs and propose new directions for future treatment of TAAs.

Resuscitative Endovascular Balloon Occlusion of the Aorta: Principles, Initial Clinical Experience, and Considerations for the Anesthesiologist

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an endovascular technique that allows for temporary occlusion of the aorta in patients with severe, life-threatening, trauma-induced noncompressible hemorrhage arising below the diaphragm. REBOA utilizes a transfemoral balloon catheter inserted in a retrograde fashion into the aorta to provide inflow control and support blood pressure until definitive hemostasis can be achieved. Initial retrospective and registry clinical data in the trauma surgical literature demonstrate improvement in systolic blood pressure with balloon inflation and improved survival compared to open aortic cross-clamping via resuscitative thoracotomy. However, there are no significant reports of anesthetic implications and perioperative management in this challenging cohort. In this narrative, we review the principles, technique, and logistics of REBOA deployment, as well as initial clinical outcome data from our level-1 American College of Surgeons-verified trauma center. For anesthesiologists who may not yet be familiar with REBOA, we make several suggestions and recommendations for intraoperative management based on extrapolation from these initial surgical-based reports, opinions from a team with increasing experience, and translated experience from emergency aortic vascular surgical procedures. Further prospective data will be necessary to conclusively guide anesthetic management, especially as potential complications and implications for global organ function, including cerebral and renal, are recognized and described.