Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms.

OBJECTIVE: The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy. METHODS: The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence. RESULTS: A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed. CONCLUSION: The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

Physician-Modified Stent-Grafts Created in the Three-Dimensionally Aortic Template Have Better Reliability and Greater Alignment With the Target Vessels Than Stent-Grafts Modified Based on Measurements From Computed Tomography.

PURPOSE: Physician-modified stent-grafts (PMSG) are widely used, especially when a patient's condition precludes waiting for a custom-made device. In recent years, the modification process has been upgraded using 3-dimensional (3D) aortic templates. Nonetheless, the reliability of PMSG and accuracy of fenestration alignment with the target vessel are not known. Thus, the study is aimed to fulfill the gap in current knowledge. MATERIALS AND METHODS: Ten computed tomographic (CT) scans of aortic aneurysm previously treated with the fenestrated endovascular repair were selected to 3D-print aortic templates and elastic vessel phantoms. Two vascular surgeons performed fenestrations using the 3D template and modification plan based on CT measurements. Two operators each performed 10 fenestrated stent-grafts in the aortic template and 10 using CT measurements, for a total of 40 fenestrated stent-grafts. Then, stent-grafts were implanted in elastic vessel phantoms, which served to evaluate fenestration alignment with the target vessel. The alignment was judged in a 5-point scale: 0%, 1% to 25%, 26% to 50%, 51% to 75%, and 76% to 100%. The distances between fenestrations served to calculate interobserver variability for both methods. The measurements were processed as interclass correlation coefficient (ICC), Pearson and Spearman correlation, and Bland-Altman plots. RESULTS: PMSG created with a 3D template had higher interclass correlation coefficient values and Pearson/Spearman correlation than fenestrations created from CT measurements. The rate of fenestration alignment with the target vessel was higher for PMSG created with a 3D template (p=0.007). CONCLUSIONS: PMSGs created with a 3D template are more reliable and have better fenestration alignment with the target vessel than PMSGs created based on CT measurements.

Off-the-Shelf Strategy for Endovascular Aneurysm Repair of Ectopic, Dominant, Renal Artery Originating From the Aortic Bifurcation: Case Report.

INTRODUCTION: An ectopic renal artery originating from the aortic bifurcation can strongly interfere with surgical or endovascular intervention in the infrarenal aorta. CASE: We present an infrarenal symptomatic aneurysm with a right ectopic/pelvic kidney associated with 1 renal artery originating from the aortic bifurcation. RESULT: During an endovascular aortic repair (EVAR) procedure, the dominant ectopic right kidney was perfused by an iliac branch device (IBD) used as an iliac extension. However, out of instructions for use (IFU), this is an "off-the-shelf" resolution for this type of rare case. CONCLUSION: The use of an "off-the-shelf" IBD to perform an EVAR with an ectopic renal artery, in patients unfit for open surgery, is a potentially valuable option.

Questionable Long-Term Results of the Extended Provisional Extension to Induce Complete Attachment (E-PETTICOAT) Technique in the Management of Chronic Type B Aortic Dissection.

BACKGROUND: Published interim results of the extended provisional extension to induce complete attachment (e-PETTICOAT) technique suggested favorable remodeling in chronic type B Aortic Dissection (cTBAD). This report presents long-term results of the e-PETTICOAT technique for the management of cTBAD (without aneurysmal dilatation). METHODS: Patients with cTBAD below the 55 mm aortic size were eligible for the management using the e-PETTICOAT technique. Follow-up was conducted at 1, 2 and 5 years based on the computed tomography angiogram. All the presurgery risk factors (entry >1 cm, inner curve entry, fusiform index >0.65, false lumen > 22 mm, aortic size >40 mm, recurrent pain or hypertension, and Stanford Dissection Risk Calculation) and postsurgery complications were examined in the study. RESULTS: A total of 20 patients underwent the e-PETTICOAT surgery. The survival rate at 1, 2, and 5 years was 75%, 70%, and 64%, respectively, and the percentage of patients without any reinterventions was 100%, 93%, and 18%. Aortic degeneration was recognized in 30%, 55%, and 85% of the patients. Only 3 of the 20 patients were alive and without any reintervention after 5 years. The receiver operating curve analysis does not indicate any factor that would predict the remodeling result in the long-term follow-up. CONCLUSIONS: The use of e-PETTICOAT technique in cTBAD might not have a beneficial influence on the long-term results.

The Rate of Postoperative Complications in Complicated Acute, and Subacute Type B Aortic Dissections after TEVAR vs. PETTICOAT Procedures: Systematic Review and Meta-Analysis.

Background and Objectives: Provisional extension to induce complete attachment (PETTICOAT) is suggested as being associated with a lower incidence of aorta-related events and fewer reinterventions compared to thoracic endovascular aortic repair (TEVAR) in patients with complicated acute, and subacute type B aortic dissections. Materials and Methods: This article is a systematic review and meta-analysis following the PRISMA guidelines. The Medline, PubMed, Embase, and Cochrane databases were searched, starting on 21 February 2022 and ending on 22 June 2022, to identify studies that investigated the rate of postoperative complications in patients treated with the PETTICOAT compared to the TEVAR. A random effects meta-analysis was performed. Of 2350 studies, 5 studies involving 360 patients were included: 143 patients after the PETTICOAT procedure and 217 after the TEVAR. Results: The meta-analysis of all studies showed that the rate of secondary endovascular reinterventions was smaller in patients treated with the PETTICOAT (n = 3 studies; OR, 0.30; 95% CI, 0.10 to 0.94; p = 0.04). The results of other postoperative complications (30-day mortality, mortality during follow-up, paraplegia, stroke, and occurrence of endoleak) were lower in the PETTICOAT group but were not statistically significant. The rate of postoperative renal failure was lower in patients treated with the TEVAR (n = 4; OR, 1.08; 95% CI, 0.46 to 2.51; p = 0.86). Conclusion: This meta-analysis suggests that the PETTICOAT procedure is related to the lower rate of secondary endovascular reinterventions for complicated acute, and subacute type B aortic dissections.

Effects of Sterilization Methods on Different 3D Printable Materials for Templates of Physician-Modified Aortic Stent Grafts Used in Vascular Surgery-A Preliminary Study.

Three-dimensionally-printed aortic templates are increasingly being used to aid in the modification of stent grafts in the treatment of urgent, complex aortic disorders, often of an emergency nature. The direct contact between the aortic template and the stent graft implies the necessity of complete sterility. Currently, the efficacy of sterilizing aortic templates and the effect of sterilization on the geometry of tubular aortic models are unknown. A complex case of aortic arch dissection was selected to prepare a 3D-printed aortic arch template, which was then manufactured in six popular printing materials: polylactic acid (PLA), nylon, polypropylene (PP), polyethylene terephthalate glycol (PETG), and a rigid and flexible photopolymer resin using fused deposition modeling (FDM) and stereolithography (SLA). The 3D models were contaminated with Geobacillus stearothermophilus broth and Bacillus atrophaeus. The sterilization was performed using three different methods: heat (105 °C and 121 °C), hydrogen peroxide plasma, and ethylene oxide gas. Before and after sterilization, the aortic templates were scanned using computed tomography to detect any changes in their morphology by comparing the dimensions. All sterilization methods were effective in the elimination of microorganisms. Steam sterilization in an autoclave at 121 °C caused significant deformation of the aortic templates made of PLA, PETG, and PP. The other materials had stable geometries, and changes during mesh comparisons were found to be submillimeter. Similarly, plasma, gas, and heat at 105 °C did not change the shapes of aortic templates observed macroscopically and using mesh analysis. All mean geometry differences were smaller than 0.5 mm. All sterilization protocols tested in our study were equally effective in destroying microorganisms; however, differences occurred in the ability to induce 3D object deformation. Sterilization at high temperatures deformed aortic templates composed of PLA, PETG, and PP. This method was suitable for nylon, flexible, and rigid resin-based models. Importantly, plasma and gas sterilization were appropriate for all tested printing materials, including PLA, PETG, PP, nylon, flexible and rigid resins. Moreover, sterilization of all the printed models using our novel protocol for steam autoclaving at 105 °C was also 100% effective, which could represent a significant advantage for health centers, which can therefore use one of the most popular and cheap methods of medical equipment disinfection for the sterilization of 3D models as well.

Arterial reconstruction with human bioengineered acellular blood vessels in patients with peripheral arterial disease.

OBJECTIVE: Vascular conduit is essential for arterial reconstruction for a number of conditions, including trauma and atherosclerotic occlusive disease. We have developed a tissue-engineered human acellular vessel (HAV) that can be manufactured, stored on site at hospitals, and be immediately available for arterial vascular reconstruction. Although the HAV is acellular when implanted, extensive preclinical and clinical testing has demonstrated that the HAV subsequently repopulates with the recipient's own vascular cells. We report a first-in-man clinical experience using the HAV for arterial reconstruction in patients with symptomatic peripheral arterial disease. METHODS: HAVs were manufactured using human vascular smooth muscle cells grown on a biodegradable scaffold. After the establishment of adequate cell growth and extracellular matrix deposition, the vessels were decellularized to remove human cellular antigens. Manufactured vessels were implanted in 20 patients with symptomatic peripheral arterial disease as above-knee, femoral-to-popliteal arterial bypass conduits. After HAV implantation, all patients were assessed for safety, HAV durability, freedom from conduit infection, and bypass patency for 2 years. RESULTS: Twenty HAVs were placed in the arterial, above-knee, femoral-to-popliteal position in patients with rest pain (n = 3) or symptomatic claudication (n = 17). All HAVs functioned as intended and had no evidence of structural failure or rejection by the recipient. No acute HAV infections were reported, but three surgical site infections were documented during the study period. Three non-HAV-related deaths were reported. One vessel developed a pseudoaneurysm after suspected iatrogenic injury during a balloon thrombectomy. No amputations of the HAV implanted limb occurred over the 2-year period, and no HAV infections were reported in approximately 34 patient-years of continuous patient follow-up. CONCLUSIONS: Human tissue engineered blood vessels can be manufactured and readily available for peripheral arterial bypass surgery. Early clinical experience with these vessels, in the arterial position, suggest that they are safe, have acceptable patency, a low incidence of infection, and do not require the harvest of autologous vein or any cells from the recipient. Histologic examination of tissue biopsies revealed vascular remodeling and repopulation by host cells. This first-in-man arterial bypass study supports the continued development of human tissue engineered blood vessels for arterial reconstruction, and potential future expansion to clinical indications including vascular trauma and repair of other size-appropriate peripheral arteries.

Complete Entry and Re-entry Neutralization protocol in endovascular treatment of aortic dissection.

There have been indisputable developments in techniques for stabilizing acute aortic syndromes. However, aneurysmal degeneration following aortic dissection remains a problem to be solved. The currently available treatment options for aortic dissection still fail to take into account the known risk factors for aneurysmal degeneration. This is why we introduced a new approach to treating patients with an aortic dissection, called Complete Entry and Re-entry Neutralization (CERN). This is our initial report on the promising interim results. MATERIAL AND METHODS: 68 patients qualified for endovascular treatment of an acute or chronic aortic dissection. Computed tomography was performed post-operatively to assess aortic remodeling after 1/6/12/24/36 months. RESULTS: the 30-day mortality rate was 4.4%. In 29 cases (43%) unfavorable remodeling was noted in the follow-up. The most important factors leading to unfavorable remodeling were: uncovered re-entry tear including the infra-renal segment, no relining of dissection membranes and insufficient coverage of the descending aorta. We analyzed these factors to develop the CERN protocol. This concept consists of six basic rules: A. cover all entry tears, B. amplify the BMS radial force, C. use the STABILISE technique, D. consider using thrombus plugs, E. avoid stenting the visceral branches, F. spare the intercostal and lumbar side branches. CERN improves the rate of favorable remodeling from 25% to 85% (P = 0.0067). CONCLUSION: Introduction of the Complete Entry and Re-entry Neutralization protocol improves the rate of favorable remodeling following endovascular treatment of aortic dissection in mid-term follow-up in patients with diffused aortic dissection.

Relationship between aortic wall oxidative stress/proteolytic enzyme expression and intraluminal thrombus thickness indicates a novel pathomechanism in the progression of human abdominal aortic aneurysm.

The possibility that oxidative stress promotes degradation of the extracellular matrix and a relationship between intraluminal thrombus (ILT) thickness and proteolytic activity within the abdominal aortic aneurysm (AAA) wall has been suggested. In the present study, the hypothesis that thin ILT is correlated with an increase in oxidative stress-related enzymes and matrix metalloproteinase-9 (MMP-9) expression within the human AAA wall was investigated. We also studied the antioxidant activity of superoxide dismutases, catalase, glutathione peroxidase, glutathione reductase, and thioredoxin within the full-thickness AAA wall and through fluoroimmunohistochemical staining of catalase and MMP-9 expression within the inner and outer media, in relation to ILT thickness. Reactive oxygen species control the degradation and remodeling of the extracellular matrix by up-regulating proteolytic enzymes, such as MMPs. Results showed that oxidative stress and proteolytic enzyme expression were simultaneously, significantly higher within thin thrombus (≤10 mm)-covered aneurysm wall when compared with the wall covered by thick thrombus (≥25 mm). These findings provide the first demonstration, to our knowledge, of a causative link between oxidative stress instigating proteolytic enzyme expression at the tissue level and human AAA development. Presence of a thin circumferential thrombus should always be considered as a risk factor for the greatest increase in aneurysm growth rate and rupture, giving an indication for surgery timing.-Wiernicki, I., Parafiniuk, M., Kolasa-Wolosiuk, A., Gutowska, I., Kazimierczak, A., Clark, J., Baranowska-Bosiacka, I., Szumilowicz, P., Gutowski, P. Relationship between aortic wall oxidative stress/proteolytic enzyme expression and intraluminal thrombus thickness indicates a novel pathomechanism in the progression of human abdominal aortic aneurysm.

Aortic Remodeling After Extended PETTICOAT Technique in Acute Aortic Dissection Type III B.

BACKGROUND: The aim of this paper was to evaluate a new technique called an "extended" provisional extension to induce complete attachment (e-PETTICOAT) technique. METHODS: In this prospective single-center clinical study, the primary safety end mid-term remodeling is evaluated for the new endovascular technique. It was based on a standard Petticoat and limited Stabilize technique, extended by the placement of 2 covered stents within the abdominal bare metal stent as parallel iliac stent grafts down to the iliac bifurcations. Computed tomographic angiography was performed postoperatively to assess aortic remodeling after 12 and 24 months. Changes in aortic size and volumes of the false and true lumen were assessed. RESULTS: Between January 2014 and December 2015, 17 patients were treated due to acute, complicated aortic dissection type III B, according to the DaBekey classification. All patients presented with branch vessel obstruction/compromise, including six cases with aortic impending rupture. A 100% technical success rate was recorded regarding the resolution of complications. Favorable remodeling was achieved in 100% of the cases. Complete false lumen thrombosis in the thoracic, infra-renal aorta and the iliac artery was noted. A small volume (9.51 ± 6.9 mL) contrast-enhanced false lumen in the abdominal aorta was observed in 76% of cases with stable aortic size after 1 and 2 years. No visceral branch occlusion, type I endo-leak, renal insufficiency or paraplegia was recorded in follow-up. CONCLUSIONS: The expanded PETTICOAT technique was feasible in achieving favorable remodeling in acute extensive aortic dissection. Extended followup is needed to ascertain long-term results. This article presents a series of 17 cases of a new endovascular method called E-PETTICOAT (EJVES 2018 https://doi.org/10.1016/j.ejvs.2018.07.038) used in complicated acute and extensive type IIIB dissections. Favorable remodeling was achieved in 100% cases with stable aorta diameter after 1 and 2 years. It was shown that the extended PETTICOAT technique gives good remodeling in acute and extensive aortic dissection. This method can potentially provide a one-step solution and an easier alternative to FEVAR/BEVAR procedures. In order to ensure favorable results, further research is needed on a wider scale with long-term followup.

Expanded Petticoat technique to promote the reduction of contrasted false lumen volume in patients with chronic type B aortic dissection.

OBJECTIVE: This study examined the outcomes of our novel concept of expanded provisional extension to induce complete attachment strategy (Petticoat) for safety, durability, and remodeling of chronic type B dissections. METHODS: Twenty patients with chronic type B aortic dissection with aneurysmal degeneration qualified for an expanded Petticoat strategy (stent graft in the thoracic, plus additional distal bare stent into the abdominal and infrarenal aorta, followed by parallel stent grafts into common iliac arteries). Computed tomography was performed preoperatively and at 1, 6, and 12 months after surgery. RESULTS: The primary technical success was 100%. The 30-day mortality rate was 0%. At 12 months, favorable aortic remodeling and complete false lumen (FL) thrombosis were noted as 100% in the thoracic and infrarenal aorta. The volume of contrast-enhanced FL decreased from 186 ± 75.4 mL all along the dissection preoperatively (range, 70-360 mL), to 6.32 ± 5.4 mL postoperatively (range, 0.0-19.6 mL) and was only observed in the visceral aorta (P = .000089). Despite persistent flow in a small area of the FL, the maximal aortic size was stable in follow-up. Neither paraplegia nor visceral branch occlusion were noted in the follow-up. CONCLUSIONS: The treatment of aortic dissections with an expanded Petticoat strategy seems to be safe and offers good early results. It significantly reduced the volume of contrast enhanced FL. Further investigation of any subsequent results will be necessary.

Holographically-Guided Endovascular Aneurysm Repair.

Purpose: To demonstrate the feasibility of augmented reality visualization in planning and navigating endovascular aortic repair. Technique: A 77-year-old patient with abdominal aortic aneurysm was treated with endovascular repair. An augmented reality head-mounted display was used during the procedure. The aneurysm and bones were projected as 3-dimensional holograms. The operator controlled the device with gestures and voice commands (movement, rotation, cutting through, and zooming). Moreover, the hologram was placed in front of the angiography monitor and manually registered with fluoroscopy. Conclusion: Augmented reality with holographic rendering is feasible and helpful during endovascular aortic repair. Its routine use could possibly lead to shorter operating time, reduced contrast volume, and lower radiation dose; however, larger studies are required to obtain statistically significant results on the outcomes.

A 3D Printed Aortic Arch Template to Facilitate Decision-Making Regarding the Use of an Externalized Transapical Wire during Thoracic Endovascular Aneurysm Repair.

Thoracic endovascular aortic repair (TEVAR) is an established treatment option, although some anatomical challenges require a through-and-through wire technique, and subsequently transapical access via minithoracotomy can be required. It is clear that an objective tool to facilitate decision-making is needed. A 3D print of a severely angulated aortic arch was used as a template to advance a stent graft, and this was achieved after pulling the top of the wire. This simulation assisted in decision-making relating to transapical access with a wire externalization. A 3D aortic print could be used in advance to simulate the TEVAR procedure and facilitate any other decisions regarding additional transapical access.

A 3-Dimensional Printed Aortic Arch Template to Facilitate the Creation of Physician-Modified Stent-Grafts.

PURPOSE: To demonstrate the utility of a 3-dimensional (3D) printed template of the aortic arch in the construction of a fenestrated and scalloped physician-modified stent-graft (PMSG). CASE REPORT: A 73-year-old woman with descending thoracic aneurysm was scheduled for thoracic endovascular aortic repair after being disqualified for open surgery. Computed tomography angiography (CTA) revealed no proximal landing zone as the aneurysm began from the level of the left subclavian artery, so a fenestrated/scalloped PMSG was planned. To facilitate accurate placement of the openings in the graft, a 3D printed aortic arch template was prepared from the CTA data and gas sterilized. In the operating room, a Valiant stent-graft was inserted into the 3D printed template and deployed. Using ophthalmic cautery, a fenestration and a scallop were created; radiopaque markers were added. The PMSG was successfully deployed with no discrepancy between the openings and the target vessels. CONCLUSION: A 3D printed aortic arch template facilitates handmade fenestrations and scallops in PMSGs and may improve accuracy and quality.

Significant changes in combined consistent biomarkers and CTAngiography revealed during an interval of 6months before abdominal aortic aneurysm rupture.

The most commonly used predictor of rupture of abdominal aortic aneurysm (AAA) is the diameter, but this does not correlate well with the risk of rupture. Therefore, in order to make further improvements in clinical decisions regarding AAA patients, the development of additional predictive tools other than aneurysm size alone is needed. We herein report a case of a 72-year-old man with AAA that underwent rupture transformation during six months. We review the morphological features changes detected by computed tomography and also observe several alters circulating biomarkers at the same time. In the study presented essentially an association of those combined parameters with the risk of AAA impending rupture.

Beyond Diameter: Enhancing Abdominal Aortic Aneurysm Surveillance with Volumetric Assessments after Endovascular Aneurysm Repair (EVAR).

This study aimed to investigate the relationship between maximum transverse diameter (MTD) and volume measurements in patients who underwent reoperations after endovascular aneurysm repair (EVAR), and their association with the occurrence of endoleaks. The study included 51 patients who underwent EVAR and subsequent re-operations caused by endoleaks type I-III. In some number of events, multiple re-operations were needed. MTD was measured using the Horos software, and segmentations of the AAA were performed using 3D Slicer. This study first evaluated post-operative computed tomography angiography (CTA) to measure MTD and volume. Then, similar measurements were made in the control scan for re-operation qualification. Negative remodeling (increase in MTD and/or volume) was observed in 40 cases using MTD, and 48 cases using volume measurements. The volume measurement showed lower missed negatives than MTD, indicating its effectiveness in screening for negative remodeling (p < 0.001). Combining both methods identified 51 negative remodeling cases and 8 positive changes, with a higher sensitivity compared to MTD alone. The volume of the sac did not predict specific endoleak types. Decreases in MTD were observed in smaller sacs, with smaller volume changes. Volume measurement is a valuable screening tool, and combining MTD and volume enhances sensitivity. However, sac volume does not predict endoleak type.

The Influence of Individualized Three-Dimensional Holographic Models on Patients' Knowledge Qualified for Intervention in the Treatment of Peripheral Arterial Disease (PAD).

We sought to determine the role of the patient-specific, three-dimensional (3D) holographic vascular model in patient medical knowledge and its influence on obtaining a more conscious informed consent process for percutaneous balloon angioplasty (PTA). Patients with peripheral arterial disease who had been scheduled for PTA were enrolled in the study. Information regarding the primary disease, planned procedure, and informed consent was recorded in typical fashion. Subsequently, the disease and procedure details were presented to the patient, showing the patients their individual model. A patient and medical supervisor equipped with mixed reality headsets could both simultaneously manipulate the hologram using gestures. The holographic 3D model had been created on a scale of 1:1 based on computed tomography scans. The patient's knowledge was tested by the completion of a questionnaire before and after the interaction in a mixed reality environment. Seventy-nine patients manipulated arterial holograms in mixed reality head-mounted devices. Before the 3D holographic artery model interaction, the mean ± standard deviation score of the knowledge test was 2.95 ± 1.21 points. After the presentation, the score had increased to 4.39 ± 0.82, with a statistically significant difference (p = 0.0000) between the two scores. Using a Likert scale from 1 to 5, the patients had scored the use of the 3D holographic model at 3.90 points regarding its usefulness in comprehending their medical condition; at 4.04 points regarding the evaluation of the holograms as helpful in understanding the course of surgery; and rated the model at 1.99 points in reducing procedure-related stress. Using a nominal scale (know or don't know), the patients had self-assessed their knowledge of the procedure before and after the 3D model presentation, with a score of 6.29 ± 2.01 and 8.39 ± 1.54, respectively. The study group tolerated the use of head-mounted devices. Only one patient had nausea and dizziness, while four patients experienced transient eye pain. The 3D holographic arterial model aided in the understanding of patients' knowledge regarding the disease and procedure, making the informed consent process more conscious. The holograms improved the patient's self-consciousness. Mixed reality headset-related complications were rare and within acceptable rates.

Six-year outcomes of a phase II study of human-tissue engineered blood vessels for peripheral arterial bypass.

Objective: The human acellular vessel (HAV) was evaluated for surgical bypass in a phase II study. The primary results at 24 months after implantation have been reported, and the patients will be evaluated for ≤10 years. Methods: In the present report, we have described the 6-year results of a prospective, open-label, single-treatment arm, multicenter study. Patients with advanced peripheral artery disease (PAD) requiring above-the-knee femoropopliteal bypass surgery without available autologous graft options had undergone implantation with the HAV, a bioengineered human tissue replacement blood vessel. The patients who completed the 24-month primary portion of the study will be evaluated for ≤10 years after implantation. The present mid-term analysis was performed at the 6-year milestone (72 months) for patients followed up for 24 to 72 months. Results: HAVs were implanted in 20 patients at three sites in Poland. Seven patients had discontinued the study before completing the 2-year portion of the study: four after graft occlusion had occurred and three who had died of causes deemed unrelated to the conduit, with the HAV reported as functional at their last visit. The primary results at 24 months showed primary, primary assisted, and secondary patency rates of 58%, 58%, and 74%, respectively. One vessel had developed a pseudoaneurysm deemed possibly iatrogenic; no other signs of structural failure were reported. No rejections or infections of the HAV occurred, and no patient had required amputation of the implanted limb. Of the 20 patients, 13 had completed the primary portion of the study; however, 1 patient had died shortly after 24 months. Of the remaining 12 patients, 3 died of causes unrelated to the HAV. One patient had required thrombectomy twice, with secondary patency achieved. No other interventions were recorded between 24 and 72 months. At 72 months, five patients had a patent HAV, including four patients with primary patency. For the entire study population from day 1 to month 72, the overall primary, primary assisted, and secondary patency rate estimated using Kaplan-Meier analysis was 44%, 45%, and 60% respectively, with censoring for death. No patient had experienced rejection or infection of the HAV, and no patient had required amputation of the implanted limb. Conclusions: The infection-resistant, off-the-shelf HAV could provide a durable alternative conduit in the arterial circuit setting to restore the lower extremity blood supply in patients with PAD, with remodeling into the recipient's own vessel over time. The HAV is currently being evaluated in seven clinical trials to treat PAD, vascular trauma, and as a hemodialysis access conduit.

Abdominal Aortic Aneurysm Morphology as an Essential Criterion for Stratifying the Risk of Aneurysm Rupture.

The current stratification model of aneurysm rupture seems to be insufficient in some clinical cases. In our study, we determined the differences in wall structure between ruptured and unruptured aneurysms. We obtained computed tomography angiograms and categorized them into the following three groups, consisting of 49 patients each: the group with ruptured abdominal aortic aneurysms (rAAA), symptomatic (sAAA), and asymptomatic (aAAA). The three-dimensional AAA anatomy was digitally reconstructed for each patient through semi-automatically obtained segmentation, and each aneurysm was distinguished by the following three parameters: AFL (aneurysm flow lumen), ILT (intraluminal thrombus), and calcifications. The AFL volume was greater in rAAA compared with aAAA (p = 0.004), the ILT volume was greater in aAAA than in rAAA (p = 0.013), and the AFL/ILT surface ratio was bigger in rAAA than in aAAA (p < 0.001), sAAA than in aAAA (p = 0.033), and rAAA than in sAAA (p = 0.016). AFL/ILT surface*100 was defined as an independent predictive factor of rAAA to aAAA (OR 1.187; 95% CI 1.099-1.281), to sAAA (OR 1.045; 95% CI 1.004-1.087), and in sAAA vs. aAAA (OR 1.067; 95% CI 1.017-1.119). Consequently, the wall of rAAA differs significantly from unruptured aneurysms. The AFL/ILT surface ratio might indicate an increased risk of aneurysm rupture and the occurrence of symptoms in AAA.