Experimental Multi-Parametric MRI Characterization of Iliocaval Venous Thrombosis Pathological Changes.

OBJECTIVE: Iliocaval thrombotic obstruction is a challenging condition, especially since thrombus age and corresponding pathological remodeling at presentation are unknown, which directly impacts management. Our aim was to assess the ability of Magnetic Resonance Imaging (MRI) in determining age thresholds of experimentally created inferior vena cava (IVC) thrombosis in pigs. METHODS: We used a previously described swine model of IVC thrombosis. Animals underwent MRI at baseline, immediately after thrombosis creation and after a follow-up period extending from 2 to 28 days. Thirteen animals were divided into 3 groups according to disease's chronicity: acute (AG, N1 = 5), subacute (SAG, N2 = 4) and chronic group (CG, N3 = 4) with a mean thrombosis age of respectively 6.4 ± 2.5, 15.7 ± 2.8 and 28 ± 5.7 days. A T1 weighted volumetric interpolated breath-hold examination sequence was used to anatomically delineate IVC thrombus as a region of interest. Three other MRI sequences were used to assess thrombus signal. RESULTS: Kruskal-Wallis showed a statistically significant difference in T1 relaxation times after contrast injection (P = .026) between the 3 groups of chronicity: AG (360.2 ± 102.5) was significantly different from CG (336.7 ± 55.2 ms; P = .003) and SAG (354.1 ± 89.7 ms) was significantly different from AG (P = .027). There was a statistically significant difference in native T2 relaxation times (P = .038) between the 3 groups: AG (160 ± 86.7 ms) was significantly different from SAG (142.3 ± 55.4 ms; P = .027) and SAG was significantly different from CG (178.4 ± 11.7 ms; P = .004). CONCLUSIONS: This study highlighted MRI characteristics in a swine model that may have the potential to significantly differentiate a subacute and a chronic stage from an acute stage of deep venous thrombosis in humans. Further clinical studies in humans are warranted.

Intraoperative Staff Radiation Exposure During Aortic Endovascular Procedures.

BACKGROUND: The risk of radiation exposure in the surgical operating room (OR) and/or catheterization laboratory is now well established. Complex endovascular procedures often require multiple approaches and different positioning of the staff members around the patient, potentially increasing the levels of radiations exposure. Our goal was to evaluate the levels of radiation exposure of the members of the staff during endovascular aortic procedures in order to propose radioprotection optimization. METHODS: We included 41 aortic endovascular procedures out of 114 procedures performed between January 12, 2014, and August 31, 2015, including 24 standard endovascular aortic aneurysm repair (EVAR), 7 EVAR with iliac branch (EVARib), 8 complex fenestrated/branched EVAR (F/B EVAR), and 2 thoracic EVAR (TEVAR). Procedures were performed in an OR equipped with a carbon fiber table and a mobile fluoroscopy C-arm. We collected the usual dosimetry data given by the C-arm as well as the patient's peak skin dose (PSD). In all staff members, radiation exposure was measured with thermoluminescent chip dosimeters placed on both temples, on posterior sides of both hands, and on both lower legs. RESULTS: PSD levels were low for EVAR because 24 patients had values below the reading threshold. PSD significantly increased with more complex procedures. Main operator (MO) received the higher level of irradiation on whole body, hands, and ankles. Eye lenses irradiation was higher on both assistant operators (AOs). Other members received low levels of irradiation. We found a high ranges of radiation exposure with a high risk of exposure for the AO, mainly for F/B EVAR and EVARib. CONCLUSIONS: Even if all personal protections are used, staff positioning is a major point that must be considered. If MO is supposed to be the most exposed to X-rays, specific conditions of positioning of the AO may be at risk of exposure.

What We Know From Reports on Type III Endoleak in the Literature.

Objective: To analyse case reports published on the latest generations of endograft (EG) and understand the mechanisms of type III endoleak (EL) development. Methods: A literature review was undertaken of English language case reports and series that concerned modular junction or component disconnection (type IIIa EL) and fabric perforations (type IIIb EL) after endovascular aneurysm repair. Results: Of the 2 785 studies, 56 full texts were chosen to review 73 cases. Type III EL was diagnosed with computed tomography angiography in 67.1% and digital subtraction angiography in 12.3%; the rest were identified during surgery. Of the 73 EG, 65 (89.0%) were made of polyethylene terephthalate and seven (9.6%) were polytetrafluoroethylene. The type of material was not mentioned in one (1.4%) case report. There were 25 (34.2%) type IIIa and 48 (65.8%) type IIIb EL. The most frequent were trunk-trunk in nine (12.3%) and trunk-limb overlap separations in 14 (19.2%). Type IIIb EL in the trunk area was identified in 27 (37.0%) cases, while 21 (28.8%) defects were found in the limbs. Stent fractures were recognised as an underlying mechanism of type IIIb EL development in one report. A combination of fabric lesions in the trunk and limb area was found in one case. Seven type IIIb EL were related to suture disruption or suture-fabric abrasions. Four cases were related to stent-fabric abrasions, and two developed as a result of fabric fatigue owing to kinking. Information on the mechanisms of degradation was only occasionally and scarcely presented. Given the small number of reports and lack of detailed analysis, no definitive conclusions could be drawn. Conclusion: The available information is scarce and does not allow any definitive conclusions to be drawn on the mechanisms that lead to the development of type III EL. Further explant analyses would be beneficial.

Update About the Management of Low-Density Lipoprotein Cholesterol and Hypertriglyceridemia in Lower Extremity Peripheral Artery Disease Patients: Consensus of the French Society of Vascular Medicine and the French Society for Vascular and Endovascular Surgery.

BACKGROUND: A French intersociety consensus on behalf the Société Française de Médecine Vasculaire and the Société de Chirurgie Vasculaire et Endovasculaire was proposed in 2021 for the management of patients with lower extremity peripheral artery disease (LEAD). Recent studies have been published and an update of this consensus about the management of low-density lipoprotein cholesterol (LDLc) and hypertriglyceridemia was required. METHODS: A steering committee of 12 vascular physicians and surgeons defined questions of interest about LDLc and hypertriglyceridemia management. A French expert panel voted the proposals. Consensus was considered to have been achieved if more than 80% of the responses corresponded to either "Agreement" or "Disagreement". RESULTS: Among the 56 experts who were asked to participate, 46 (82%) accepted. After the first round of the Delphi procedure, the 4 proposals reached consensus. The following suggestions and recommendations were approved: 1. For LEAD patients treated by the highest tolerated statin dose ± ezetimibe and who have an LDLc ≥0.70 g/L, we recommend adding a proprotein convertase subtilisin/kexin type 9 inhibitor. 2. For LEAD patients treated by statin and who have elevated triglyceride level between ≥150 mg/dL and ≤500 mg/dL, we suggest adding Icosapent Ethyl. 3. Before adding Icosapent Ethyl in LEAD patients treated with statin, we suggest looking for symptoms that may suggest atrial fibrillation. 4. For LEAD patients treated by Icosapent Ethyl and who have symptoms that suggest atrial fibrillation, we recommend performing an electrocardiogram. CONCLUSIONS: This update will help clinicians to improve LEAD patient management.

Editor's Choice -- Type IIIb Endoleaks: Fabric Perforations of Explanted New Generation Endoprostheses.

OBJECTIVE: To analyse explanted endografts (EGs) and describe fabric degradation responsible for type IIIb endoleaks. METHODS: As part of the European collaborative retrieval programme, 32 EGs with fabric defects on macroscopic evaluation were selected. The explanted EGs were processed and studied based on the ISO 9001 certified standard protocol. It includes instructions on the collection, transportation, cleaning, and examination of explanted material. The precise analysis was performed with a digital microscope of 20 - 200 times magnification. Possible perforation mechanisms were assessed in stress tests. RESULTS: The median time to explantation of the 32 EGs was 54 months. The explants included 65 separate EG modules, with 46 (70.8%) having a combined 388 fabric perforations. Each EG had a median of 4.79 mm2 (interquartile range [IQR] 9.86 mm2) of cumulated hole area (an average of 0.13% of an EG's area). There were 239 (61.6%) expanded polytetrafluoroethylene (ePTFE; 11 EGs) and 149 (38.4%) polyethylene terephthalate (PET; 21 EGs) fabric ruptures, with no difference in hole distribution between these types of material. Overall, 126 (32.5%) stent related and 262 (67.5%) non-stent related fabric perforations were identified. Perforations caused by fabric fatigue in ePTFE (151, 63.2%) and material kinking in PET (41, 27.5%) were the most common. The stent related perforations were larger in size (0.80 mm2) than non-stent related perforations (0.19 mm2); p < .001. Wider interstent spaces and prolonged implantation duration were associated with an increased risk of stent related perforation development; p < .001 and p = .004, respectively. Large stent related perforations were also detected in the short term, suggesting mechanical issues as underlying causes. CONCLUSION: The fabric of EGs may degrade and lead to the development of perforations. The largest perforations are stent related. Their occurrence and size depend on the implantation time and the EG shape affected by arterial tortuosity. The conclusions are limited to the samples from a select explant group.

Do Not Forget the Oncovascular: Acute Limb Ischaemia Due to Aortic Epithelioid Angiosarcoma.

Introduction: Aortic epithelioid angiosarcoma (AEA) is a rare malignant tumour and can cause acute limb ischaemia. Report: A 66 year old man was admitted with acute pulmonary oedema due to bilateral renal artery stenosis. An incidental osteolytic left sacral lesion was found on computed tomography angiography, and extensive work up revealed an AEA. Follow up was marked by acute left lower limb ischaemia 13 months later and right chronic limb threatening ischaemia 15 months later. Discussion: Physicians need to consider AEA as an aetiology for acute or chronic limb ischaemia in patients with altered general status but mostly with intra-aortic irregular vegetations without any calcification and parietal involvement on computed tomography angiography.

Case Report and Literature Review of Prosthetic Cardiovascular Mucormycosis.

We report a rare case of aorto-bi-iliac prosthetic allograft mucormycosis in a 57-year-old immunocompetent patient in France. Outcome was favorable after surgery and dual antifungal therapy with liposomal amphotericin B and isavuconazole. In a literature review, we identified 12 other cases of prosthetic vascular or heart valve mucormycosis; mortality rate was 38%.

Assessment of Thoracic Endovascular Aortic Repair Using Relay Proximal Scallop: Results of a French Prospective Multicentre Study.

OBJECTIVE: A proximal scallop design allows aortic arch repair without complex endovascular manipulation in the aortic arch. The aim was to assess the safety and efficacy at one year of the Relay proximal scallop stent graft. METHODS: A prospective multicentre study evaluated consecutive patients treated with the Relay proximal scallop stent graft in 10 French aortic centres. All consecutive patients eligible for elective thoracic endovascular repair with proximal scallop in the 10 participating centres between January 2015 and July 2018 were included. Primary endpoints were 30 day mortality, stroke, and spinal cord ischaemia (SCI) rates. Outcomes including safety and efficacy, technical and clinical success, all cause death, neurological events, vessel patency, and device specific complications were analysed. Survival and survival without severe complications were estimated using Kaplan-Meier estimates. RESULTS: Ten aortic centres treated 40 patients for thoracic aortic aneurysm (45%), penetrating atherosclerotic aneurysm (30%), and dissection (25%). Half of the procedures (50%) targeted zone 0 of the aortic arch (zone 0 in 17.5% and zones 0/1 in 32.5%), 37.5% targeted zone 2 (35% zone 2 alone; 2.5% zones 1/2), and 15% targeted zone 1 (12.5% zone 1 alone). Median follow up was one year. Thirty day mortality, stroke, and SCI rates were 10%, 5%, and 0% respectively. Primary technical success was 95%. Type Ia, Ib, and III endoleaks rates were 5.4%, 0%, and 0% respectively at one month. The overall mortality rate at one year was 17.5%. Aneurysm expansion was > 5 mm in one case at one year associated with type Ia endoleak (3%). There was no supra-aortic trunk thrombosis, one (2%) graft kink, and no migration. CONCLUSION: One year outcomes showed that the Relay proximal scallop stent graft is an acceptable answer to thoracic aortic disease to deal with short proximal landing zones.

Mortality and Delays of Management of Acute Mesenteric Ischemia: The Need of a Dedicated Program.

BACKGROUND: To study the mortality and delays of management of patients with acute mesenteric ischemia (AMI) admitted to the emergency department of a tertiary hospital and identify risk factors for 1-month mortality. METHODS: A single-center and retrospective study including all consecutive patients treated for AMI from January 2008 to December 2018 was conducted. Short- and medium-term survival was studied with a Kaplan-Meier analysis. Delays before diagnosis and surgical intervention were collected. To determine factors associated with mortality at 1 month postoperatively, univariate and multivariate analyzes were performed. RESULTS: The survival rate of the 67 included patients was 55.22% at 1 month and 37.31% at 1 year. In-hospital mortality was 50.74%. The average delay between admission and diagnosis was 4.83 ± 5.03 hr (95% confidence interval [CI], 3.60-6.05), and the delay between admission and surgical treatment was 10.64 ± 8.80 hr (95% CI, 8.49-12.79). The independent variables associated with an increased mortality at 1 month postoperatively in the univariate analysis were age >65 years old (odds ratio [OR] = 3.52; P = 0.046), lactate >3.31 mmol/l at admission (H0) (OR = 7.38; P < 0.001), lactate >3.32 mmol/l on day 1 (H24) (OR = 5.60; P = 0.002), creatinine >95.9 µmol/l at H0 (OR = 4.66; P = 0.004), aspartate aminotransferase (AST) >59 U/l at H0 (OR = 3.55; P = 0.017), and having hypertension as comorbidity (OR = 9.32; P = 0.040). Early curative anticoagulation (z = -2.4; P = 0.016) was an independent protective factor for mortality, and lactate >3.31 mmol/l at H0 (z = 2.62; P = 0.009) was an independent predictor factor of mortality at 1 month postoperatively in the multivariate analysis. CONCLUSION: AMI remains a serious and lethal condition with delays of surgical management remaining too long due to a lack of a dedicated therapeutic protocol allowing an early diagnosis.

Mechanical Performance Assessment of Physician Modified Aortic Stent Graft.

OBJECTIVE: This study aimed to compare various fenestration configurations of physician modified aortic stent grafts in order to identify which design parameters have a significant influence on the mechanical behaviour of the fenestration. METHODS: the fenestration configurations were considered according to different manufacturing parameters: cutting technique, fenestration reinforcement, suture material, reinforcement loop design, and number of suture points. The performance of the graft/bridging stent assembly was assessed at various levels: (1) branch pull out force; (2) fenestration enlargement and rupture strength; (3) balloon angioplasty resistance; and (4) behaviour under cyclic fatigue. RESULTS: Sixty manual fenestrations were created. The tests performed on the fenestrations had several main findings. First, reinforcement increased the radial force on the branch, which increased the pull out force; this may limit migration of the bridging stent in vivo. The phenomenon was amplified with a snare reinforced fenestration, which seemed to be the most efficient. Moreover, increasing the number of suture passes also appeared to increase the branch extraction force securing the assembly. The enlargement tests showed that non-reinforced fenestrations had the weakest radial strength. This was confirmed with the balloon angioplasty test, which showed that these latter specimens undergo the most significant textile degradation. After fatigue tests, all fenestrations were larger, showing that elastic recoil was incomplete in all samples. The largest recoil was observed in the non-reinforced ophthalmological cautery (OC) fenestrations (40%). Regarding the behaviour of the samples up to rupture, all samples behaved in a similar way; however, the double loop fenestration strength level was the highest. CONCLUSION: This study demonstrated that the snare double loop reinforcement has an advantage regarding durability of the graft branch assembly. Moreover, non-reinforced fenestrations show signs of weakness and lack of stability, which questions the in situ or laser fenestration procedures.

Midterm Results of Physician-Modified Stent Grafts for Thoracoabdominal and Complex Abdominal Aortic Aneurysms Repair.

BACKGROUND: To assess midterm results of physician-modified stent grafts (PMSG) for the treatment of emergent complex abdominal and thoracoabdominal aortic aneurysms (TAAA) in high-risk patients. METHODS: All consecutive patients with emergent complex abdominal or TAAA undergoing PMSG technique between January 2012 and July 2019 were retrospectively included. Indications for PMSG were symptomatic aneurysms and rapidly growing aneurysms >70 mm. Ruptured aneurysms were excluded. RESULTS: Thirty-three patients (mean age: 74 +/- 11 years) were included. The mean aneurysm diameter was 76 +- 20 mm. Patients presented with TAAA (n = 20, 61%), complex abdominal aortic aneurysms (CAAA, n = 9, 27%), type I endoleak after previous endovascular aneurysm repair (n = 3, 9%) and intramural aortic hematoma (n = 1, 3%). Chimney technique was performed in addition to PMSG in seven cases (21%). Intraoperative adverse events were recorded in seven cases (35%) in the TAAA group and one case (11%) in the CAAA group. In-hospital mortality rate was 15% (n = 3) in the TAAA group and 11% (n = 1) in the CAAA group. Moderate to severe complications were recorded in 45% of cases (n = 15). Spinal cord ischemia occurred in two cases (6%, one case without residual deficit and one with minor motor deficit). One (3%) patient required transient hemodialysis. One patient presented with early aortic rupture and required an open conversion. The mean follow-up duration was 31 months (1-79). Overall survival estimates were 81.4% (95% confidence interval [CI]: 63.1.-91.2) at 1 year and 71.6% (95% CI: 52.6-84.1) at 2 years. Freedom from reintervention rates at 1 and 2 years were 61.2% (95% CI: 41.7-75.9) and 57.4% (95% CI: 37.9-72.8). Target vessel primary patency rates at 1 and 2 years were 99.2% (95% CI: 94.2-99.9) and 97.7% (95% CI: 90.7-99.4). CONCLUSIONS: PMSG for high-risk patients with complex aneurysms provided acceptable technical success and excellent target vessel patency rates but were associated with a 12% in-hospital mortality rate. Reinterventions were frequent. This technique should be limited to selected high-risk patients for whom the risk of rupture in the short-term is deemed too high to wait for graft manufacturing of custom-made device.

Editor's Choice - Infective Native Aortic Aneurysms: A Delphi Consensus Document on Terminology, Definition, Classification, Diagnosis, and Reporting Standards.

OBJECTIVE: There is no consensus regarding the terminology, definition, classification, diagnostic criteria, and algorithm, or reporting standards for the disease of infective native aortic aneurysm (INAA), previously known as mycotic aneurysm. The aim of this study was to establish this by performing a consensus study. METHODS: The Delphi methodology was used. Thirty-seven international experts were invited via mail to participate. Four two week Delphi rounds were performed, using an online questionnaire, initially with 22 statements and nine reporting items. The panellists rated the statements on a five point Likert scale. Comments on statements were analysed, statements revised, and results presented in iterative rounds. Consensus was defined as ≥ 75% of the panel selecting "strongly agree" or "agree" on the Likert scale, and consensus on the final assessment was defined as Cronbach's alpha coefficient > .80. RESULTS: All 38 panellists completed all four rounds, resulting in 100% participation and agreement that this study was necessary, and the term INAA was agreed to be optimal. Three more statements were added based on the results and comments of the panel, resulting in a final 25 statements and nine reporting items. All 25 statements reached an agreement of ≥ 87%, and all nine reporting items reached an agreement of 100%. The Cronbach's alpha increased for each consecutive round (round 1 = .84, round 2 = .87, round 3 = .90, and round 4 = .92). Thus, consensus was reached for all statements and reporting items. CONCLUSION: This Delphi study established the first consensus document on INAA regarding terminology, definition, classification, diagnostic criteria, and algorithm, as well as reporting standards. The results of this study create essential conditions for scientific research on this disease. The presented consensus will need future amendments in accordance with newly acquired knowledge.