The optimal operative protocol to accomplish CO2-EVAR resulting from a prospective interventional multicenter study.

OBJECTIVES: Carbon dioxide (CO2) angiography for endovascular aortic repair (CO2-EVAR) is used to treat abdominal aortic aneurysms (AAAs), especially in patients with chronic kidney disease or allergy to iodinated contrast medium (ICM). However, some technical issues regarding the visualization of the lowest renal artery (LoRA) and the best quality image through angiographies performed from pigtail or introducer sheath are still unsolved. The aim of this study was to analyze different steps of CO2-EVAR to create an operative standardized protocol. METHODS: Patients undergoing CO2-EVAR were prospectively enrolled in five European centers from 2019 to 2021. CO2-EVAR was performed using an automated injector (pressure, 600 mmHg; volume, 100 cc); a small amount of ICM was injected in case of difficulty in LoRA visualization. LoRA visualization and image quality (1 = low, 2 = sufficient, 3 = good, 4 = excellent) were analyzed at different procedure steps: preoperative CO2 angiography from pigtail and femoral introducer sheath (first step), angiographies from pigtail at 0%, 50%, and 100% of proximal main body deployment (second step), contralateral hypogastric artery (CHA) visualization with CO2 injection from femoral introducer sheath (third step), and completion angiogram from pigtail and femoral introducer sheath (fourth step). Intraoperative and postoperative CO2-related adverse events were also evaluated. χ2 and Wilcoxon tests were used for statistical analysis. RESULTS: In the considered period, 65 patients undergoing CO2-EVAR were enrolled (55/65 [84.5%] male; median age, 75 years [interquartile range (IQR), 11.5 years]). The median ICM injected was 17 cc (IQR, 51 cc); 19 (29.2%) of 65 procedures were performed with 0 cc ICM. Fifty-five (84.2%) of 65 patients underwent general anesthesia. In the first step, median image quality was significantly higher with CO2 injected from femoral introducer (pigtail, 2 [IQR, 3] vs introducer, 3 [IQR, 3]; P = .008). In the second step, LoRA was more frequently detected at 50% (93% vs 73.2%; P = .002) and 100% (94.1% vs 78.4%; P = .01) of proximal main body deployment compared with first angiography from pigtail; similarly, image quality was significantly higher at 50% (3 [IQR, 3] vs 2 [IQR, 3]; P ≤ .001) and 100% (4 [IQR, 3] vs 2 [IQR, 3]; P = .001) of proximal main body deployment. CHA was detected in 93% cases (third step). The mean image quality was significantly higher when final angiogram (fourth step) was performed from introducer (pigtail, 2.6 ± 1.1 vs introducer, 3.1 ± 0.9; P ≤ .001). The intraoperative (7.7%) and postoperative (12.5%) adverse events (pain, vomiting, diarrhea) were all transient and clinically mild. CONCLUSIONS: Preimplant CO2 angiography should be performed from femoral introducer sheath. Gas flow impediment created by proximal main body deployment can improve image quality and LoRA visualization with CO2. CHA can be satisfactorily visualized with CO2 alone. Completion CO2 angiogram should be performed from femoral introducer sheath. This operative protocol allows performance of CO2-EVAR with 0 cc or minimal ICM, with a low rate of mild temporary complications.

Machine learning detects symptomatic patients with carotid plaques based on 6-type calcium configuration classification on CT angiography.

OBJECTIVES: While the link between carotid plaque composition and cerebrovascular vascular (CVE) events is recognized, the role of calcium configuration remains unclear. This study aimed to develop and validate a CT angiography (CTA)-based machine learning (ML) model that uses carotid plaques 6-type calcium grading, and clinical parameters to identify CVE patients with bilateral plaques. MATERIAL AND METHODS: We conducted a multicenter, retrospective diagnostic study (March 2013-May 2020) approved by the institutional review board. We included adults (18 +) with bilateral carotid artery plaques, symptomatic patients having recently experienced a carotid territory ischemic event, and asymptomatic patients either after 3 months from symptom onset or with no such event. Four ML models (clinical factors, calcium configurations, and both with and without plaque grading [ML-All-G and ML-All-NG]) and logistic regression on all variables identified symptomatic patients. Internal validation assessed discrimination and calibration. External validation was also performed, and identified important variables and causes of misclassifications. RESULTS: We included 790 patients (median age 72, IQR [61-80], 42% male, 64% symptomatic) for training and internal validation, and 159 patients (age 68 [63-76], 36% male, 39% symptomatic) for external testing. The ML-All-G model achieved an area-under-ROC curve of 0.71 (95% CI 0.58-0.78; p < .001) and sensitivity 80% (79-81). Performance was comparable on external testing. Calcified plaque, especially the positive rim sign on the right artery in older and hyperlipidemic patients, had a major impact on identifying symptomatic patients. CONCLUSION: The developed model can identify symptomatic patients using plaques calcium configuration data and clinical information with reasonable diagnostic accuracy. CLINICAL RELEVANCE: The analysis of the type of calcium configuration in carotid plaques into 6 classes, combined with clinical variables, allows for an effective identification of symptomatic patients. KEY POINTS: • While the association between carotid plaques composition and cerebrovascular events is recognized, the role of calcium configuration remains unclear. • Machine learning of 6-type plaque grading can identify symptomatic patients. Calcified plaques on the right artery, advanced age, and hyperlipidemia were the most important predictors. • Fast acquisition of CTA enables rapid grading of plaques upon the patient's arrival at the hospital, which streamlines the diagnosis of symptoms using ML.

Axillary artery aneurysms in pediatric patients: A narrative review.

OBJECTIVES: Axillary artery aneurysms in children are rare and multifactorial. The presenting clinical picture can range from an incidental discovery to threatening symptoms, including loss of extremity function. With the present study we aim to give a comprehensive review of the existing literature focusing on the etiology and management of this rare but threatening pathology. METHOD: A comprehensive review was made in a multi-staged manner. All identified studies have been categorized based on the type of lesions (true or false aneurysm) and their etiologies. RESULTS: The treatments differ from the extension of the lesions and from the etiology. CONCLUSIONS: Open surgery repair with great saphenous vein is still the best long-term approach, but even endovascular, embolization, or conservative management can be considered.

Experience with the Ankura Thoracic Stent Graft and In-situ Fenestration for the Left Subclavian Artery with the Fu-Through Needle - a Technical Overview and Comparison to Similar Endovascular Techniques.

Thoracic endovascular aortic repair (TEVAR) is a widespread minimally invasive procedure prevalently used to treat thoracic aortic pathologies. However, when the left subclavian artery (LSA) is involved in the pathology, a more complex surgical approach is required to guarantee the perfusion of the vertebral and brachial arteries. In fact, coverage of the LSA has been proven to be associated with a higher risk of stroke, spinal cord ischemia, and arm ischemia.Historically, carotid-subclavian bypass or subclavian transposition has been the only treatment options to restore the perfusion of the LSA. For the past 10 years, different endovascular techniques have been implemented in the endovascular armamentarium to reduce the risk of complications related to surgical treatment such as infection, bleeding, and chylothorax.Currently, physician-modified grafts, in situ fenestration, chimneys, and branched or fenestrated devices are available. The aim of this overview is to describe the technique with the Ankura thoracic stent graft and in situ fenestration with the Futhrough needle and thus to shed light on the different approaches by comparing their pros and cons.

Radiation doses for endovascular aortic repairs performed on mobile and fixed C-arm fluoroscopes and procedure phase-specific radiation distribution.

OBJECTIVE: The objective of this study was to analyze radiation risk to patients during endovascular aneurysm repair (EVAR) using mobile C-arm (MA) or fixed C-arm (FA) fluoroscopes and to describe the dose distribution during the different phases of the procedure. METHODS: Patients treated with EVAR using a single stent graft system between November 2009 and June 2016 were included in this study. The patients were divided into one of two groups (MA or FA) according to the type of C-arm used in the procedure. Data regarding patients' demographics and the total amount of contrast agent (CA) used, dose-area product, and fluoroscopy time for the procedures were prospectively recorded. Based on the dose report from the FA system, five standard and two optional phases of the procedure were identified to determine the dose distribution. RESULTS: Overall, 160 patients were included (mean age, 73.30 ± 8.97 years; 146 men); of these, 107 were treated with an MA system and 53 were treated with an FA system. The mean amounts of CA used were 108.55 ± 42.28 mL in the MA group and 85.37 ± 38.79 mL in the FA group (P = .0014). The mean total dose-area product values were 49.93 ± 38.06 Gy·cm2 in the MA group and 168.34 ± 146.92 Gy·cm2 in the FA group (P < .0001). There was no significant difference in fluoroscopy time between the groups. Per-phase analysis demonstrated that identification of the proximal landing zone and main body deployment required the most radiation, accounting for 24% of the total radiation dose. Overall, 47.6% of the exposure was due to digital subtraction angiography. CONCLUSIONS: Use of an FA system can significantly reduce the amount of CA needed but may also lead to higher radiation doses in EVAR procedures. Dose monitoring remains crucial for the safety of both patients and operators. A detailed analysis of dose distribution is possible with modern systems, which may improve the quality of monitoring in the future.

Quantification of volume changes in the descending aorta after frozen elephant trunk procedure using the Thoraflex hybrid prosthesis for type A aortic dissection.

BACKGROUND: Frozen elephant trunk (FET) is an established approach to reduce late complications of type A aortic dissection (AADA) by diminishing false lumen perfusion. Currently, surface size of aortic lumina are evaluated using Computed tomography (CT). However, this 2D method is prone to error as it evaluates dissection progression slice by slice. Volume measurement on the other hand can overcome this limitation and deliver better insights in aortic remodeling. Therefore, the aim was to quantify volume changes of the descending and abdominal aorta at short- and mid-term follow-up after FET. METHODS: Between April 2015 and March 2018, 20 patients who underwent surgical repair of AADA using the Thoraflex™ Hybrid Plexus (Vascutek, Terumo Aortic, Scotland) were included in this study. We measured volumetric change before surgical treatment, at discharge, at 12 and at 24 months based on CTAs (Computed tomography angiography). Surfaces and volumes have been analyzed using Aquarius iNtuition (TeraRecon Inc., Foster City, CA, USA). RESULTS: One hundred fifty-eight volumetric measures were obtained. The findings show a significant increase of volume of the true lumen (TL) while surface measurement of the TL did not show any significant change at other levels besides level C (diaphragm, P=0.00193). Variance analysis showed significant increase of volume, whereas no significant change was seen in false lumen. Post-hoc analysis revealed a significance at 24 months (P=0.047). CONCLUSIONS: Although previous studies outline the clinical benefit of Thoraflex hybrid prosthesis on short-term follow up, this study provides a more precise understanding of aortic remodeling based on volumetric measurement. Thus, quantification of volume changes should be included for the assessment of optimal follow-up timing and consecutive procedure planning.

Late-onset aortoesophageal fistula after treatment of a chronic type B aortic dissection with a three-step approach.

Aortoesophageal fistula is a rare but lethal complication after thoracic endovascular repair for thoracic aortic diseases. Extensive treatment is reserved for patients fit for surgery. Various technical approaches have been described; however, mortality rates are still high. Herein, we report a case of a 76-year-old woman with aortoesophageal fistula treated by a three-step treatment approach, with close collaboration between cardiothoracic and general surgery specialists. The patient required tracheostomy after the first procedure, but this was closed at 15 days. She subsequently recovered and is doing well at 3 months after surgery. Staged treatment aims to shorten operative times, to reduce the risk of anesthesia complications, and to provide the patients the time to recover after each procedure.