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Objective A crucial step in designing fenestrated stent grafts for treatment of complex aortic abdominal aneurysms is the accurate positioning of the fenestrations. The deployment of a fenestrated stent graft prototype in a patient-specific rigid aortic model can be used for design verification in vitro, but is time and human resources consuming. Numerical simulation (NS) of fenestrated stent graft deployment using the finite element analysis has recently been developed; the aim of this study was to compare the accuracy of fenestration positioning by NS and in vitro. Methods All consecutive cases of complex aortic abdominal aneurysm treated with the Fenestrated Anaconda (Terumo Aortic) in six European centers were included in a prospective, observational study. To compare fenestration positioning, the distance from the center of the fenestration to the proximal end of the stent graft (L) and the angular distance from the 0° position (C) were measured and compared between in vitro testing (L1, C1) and NS (L2, C2). The primary hypothesis was that ΔL (|L2 – L1|) and ΔC (|C2 – C1|) would be 2.5 or less mm in more than 80% of the cases. The duration of both processes was also compared. Results Between May 2018 and January 2019, 50 patients with complex aortic abdominal aneurysms received a fenestrated stent graft with a total of 176 fenestrations. The ΔL and ΔC was 2.5 mm or less for 173 (98%) and 174 (99%) fenestrations, respectively. The NS process duration was significantly shorter than the in vitro (2.1 days [range, 1.0-5.2 days] vs 20.6 days [range, 9-82 days]; P Conclusions Positioning of fenestrations using NS is as accurate as in vitro and could significantly decrease delivery time of fenestrated stent grafts.

Background Sutureless valves have recently enabled closed chest aortic valve replacement. This paper evaluates the feasibility of a robotic telemanipulation during thoracoscopic sutureless aortic valve implantation in cadavers. Methods Cadavers were prepared with a five thoracosopic trocar setting, with a transthoracic clamp inserted in the first right intercostal space and the optics inserted in the second. Seven sutureless valve implantations were scheduled using 5 Sorin Perceval and 2 Medtronic 3f Enable valves. Results In all cases performance of pericardial suspension, aortotomy and root exposure required less than 20 min. Native valve excision and sutureless bioprosthesis implantation was technically feasible in all cases. A satisfactory prosthesis sealing was ascertained visually and the absence of paravalvular leakages was assessed with a nerve hook test around the prosthetic flange. Conclusions Closed chest and robot assisted sutureless valve implantation is feasible in cadavers. Robotic technology can enhance reproducibility of the technique. Copyright © 2015 John Wiley & Sons, Ltd.

Le suivi habituel d'un anevrysme de l'aorte abdominale (AAA) apres traitement par endoprothese (EVAR) comporte la surveillance de son diametre et la detection d'une endofuite. Parmi les autres parametres proposes au clinicien pour identifier les AAA restant a risque de rupture, figure la compliance de l'AAA mais son interet n'est pas clairement defini. Le doppler tissulaire (TDI) est une modalite echographique permettant la mesure des deplacements des parois de l'AAA. Le but de cette etude etait d'analyser la compliance des AAA avant et apres EVAR, et d'en decrire l'evolution chez des patients ayant plus d'un mois de suivi. Vingt cinq patients consecutifs traites par EVAR entre fevrier 2005 et juin 2007 ont donne leur consentement eclaire pour avoir une analyse prospective du mouvement des parois de l'AAA par TDI avant EVAR et lors de chaque visite au cours du suivi. Le suivi moyen (ET) etait de 13,7 (9,7) mois. La dilatation segmentaire maximale moyenne (MMSD), la compliance segmentaire, la dilatation au diametre maximal, le module elastique de contrainte de pression (Ep) et l'indice de raideur etaient compares entre trois periodes (avant EVAR, avant la sortie et lors du dernier controle) et leur relation avec le diametre de l'AAA etait analysee. La compliance des AAA diminuait significativement immediatement apres une implantation reussie et restait stable au cours du suivi, alors que le diametre des AAA diminuait progressivement et etait statistiquement plus petit lors du dernier controle comparativement au diametre initial. La MMSD, la compliance segmentaire et la dilatation au diametre maximal etaient correlees positivement au diametre de l'AAA. Cela signifie que plus le diametre de l'AAA etait large apres EVAR reussi, plus la compliance etait elevee. A l'oppose, les pourcentages de diminution du diametre de l'AAA et de la MMSD n'etaient pas correles: il n'y avait pas de parallelisme entre la perte de compliance et la retraction de l'AAA. Cela signifie qu'il existe des modeles de perte de compliance et de retraction variables d'un AAA a l'autre au cours du suivi. Meme si la comparaison des patients sans et avec endofuite etait difficile du fait du petit effectif de ce dernier groupe (5 patients), la compliance tendait a etre plus importante en cas d'endofuite. Les mouvements de paroi d'un AAA apres EVAR reussi refletent des interactions complexes entre les composants de l'AAA traite, eux meme evolutifs au cours du temps, incluant la compliance vraie de la coque de l'AAA, la pression intrasacculaire avec des effets possiblement differents entre la pression maximale, la pression moyenne et la pression pulsee, le remodelage du thrombus, les caracteristiques de l'endoprothese et la pression systemique intra aortique. Une mesure combinee de la MMSD et de la pression intrasacculaire chez des patients sans et avec endofuite pourrait permettre d'avancer dans la comprehension du mecanisme des mouvements de parois de l'AAA apres EVAR.

Las tecnicas de imagen habituales tras la reparacion endovascular de los aneurismas (REVA) en casos de aneurismas aorticos abdominales (AAA) estan destinadas a monitorizar el diametro del AAA y detectar endofugas. Entre los parametros predictivos adicionales propuestos para identificar mejor los subgrupos de AAA que siguen presentando riesgo de rotura, se ha estudiado la motilidad de la pared tras la REVA, pero no se ha establecido de forma clara su utilidad. La eco-Doppler tisular (TDI) es una modalidad ecografica que permite realizar mediciones de la motilidad parietal a lo largo de un segmento arterial. El objetivo de este estudio fue analizar la motilidad de la pared del AAA mediante TDI antes y despues de la REVA y describir su evolucion en los pacientes con un seguimiento mayor de 1 mes. Se obtuvo el consentimiento informado de 25 pacientes consecutivos sometidos a REVA entre febrero de 2005 y junio de 2007 para ser estudiados de forma prospectiva mediante el sistema TDI antes de la REVA y en cada visita del seguimiento. La media del seguimiento fue de 13,7 (DE 9,7) meses. La media de la dilatacion maxima del segmento (MDMS), la distensibilidad del segmento, la dilatacion, el modulo elastico presion-deformacion (Ep), y la rigidez se compararon entre 3 periodos (antes de la colocacion del stent, antes del alta, y en el ultimo seguimiento), y se analizo su relacion con el diametro del AAA. Se observo una reduccion significativa en la distensibilidad del AAA inmediatamente tras la REVA, que permanecio estable durante el seguimiento posterior. Por otro lado, el diametro del AAA disminuyo progresivamente con el tiempo y fue estadisticamente menor en el ultimo control en comparacion con los valores iniciales. La MDMS, la distensibilidad del segmento, y la dilatacion del diametro maximo estuvieron relacionadas directamente con el diametro del AAA. Esto significa que cuanto mayor es el diametro del AAA tras la colocacion del stent, mayor es la magnitud que cabe esperar para estos parametros. Por el contrario, los porcentajes de reduccion del diametro del AAA y de la MDMS no estuvieron relacionados tras una REVA satisfactoria. No existio ningun paralelismo entre la perdida de distensibilidad y la reduccion del diametro a lo largo del tiempo, y no existe un unico patron respecto al diametro del AAA y la evolucion de la distensibilidad tras la REVA. A pesar de que la comparacion entre pacientes con y sin endofugas fue debil debido al tamano reducido de la muestra del primer grupo (5 pacientes con endofuga), la distensibilidad tendio a ser mayor en casos de endofuga. La motilidad de la pared del AAA tras una REVA satisfactoria refleja las complejas interacciones entre todos los componentes del aneurisma tratado con endoprotesis que evolucionan a lo largo del tiempo, incluida la distensibilidad real de la propia pared del aneurisma; la presion del saco intraaneurismatico con diferentes posibles efectos en cuanto a la presion maxima, media y del pulso; el remodelado del trombo; las caracteristicas de rigidez del implante; y la presion sistemica. La combinacion de los registros simultaneos de la MDMS con las determinaciones reales de la presion intrasacular en los pacientes con y sin endofuga mejoraria nuestro conocimiento del mecanismo de la pulsatilidad clinica en el AAA tras la REVA.

Sutureless valves have recently enabled closed chest aortic valve replacement. This paper evaluates the feasibility of a robotic telemanipulation during thoracoscopic sutureless aortic valve implantation in cadavers.Cadavers were prepared with a five thoracosopic trocar setting, with a transthoracic clamp inserted in the first right intercostal space and the optics inserted in the second. Seven sutureless valve implantations were scheduled using 5 Sorin Perceval and 2 Medtronic 3f Enable valves.In all cases performance of pericardial suspension, aortotomy and root exposure required less than 20 min. Native valve excision and sutureless bioprosthesis implantation was technically feasible in all cases. A satisfactory prosthesis sealing was ascertained visually and the absence of paravalvular leakages was assessed with a nerve hook test around the prosthetic flange.Closed chest and robot assisted sutureless valve implantation is feasible in cadavers. Robotic technology can enhance reproducibility of the technique. Copyright © 2015 John WileySons, Ltd.

Purpose: To assess numerically the flexibility and mechanical stresses undergone by stents and fabric of currently manufactured stent-grafts. Methods: Eight marketed stent-graft limbs (Aorfix, Anaconda, Endurant, Excluder, Talent, Zenith Flex, Zenith LP, and Zenith Spiral-Z) were modeled using finite element analysis. A numerical benchmark combining bending up to 180° and pressurization at 150 mmHg of the stent-grafts was performed. Stent-graft flexibility, assessed by the calculation of the luminal reduction rate, maximal stresses in stents, and maximal strains in fabric were assessed. Results: The luminal reduction rate at 90° was ‹

Background Carotid angioplasty and stenting has been proposed as an alternative to carotid endarterectomy (CEA) in patients deemed as at high risk for this surgical procedure. To date, definitely accepted criteria to identify “high-risk” patients for CEA do not exist. Our objective was to assess the relevance of numerous supposed high-risk factors in our experience, as well as their possible effect on our early postoperative results. Methods A retrospective review of 1,033 consecutive CEAs performed during a 5.6-year period at a single institution was conducted (Vascular Surgery Department, St. Etienne University Hospital, France). Early results in terms of mortality and neurologic events were recorded. Univariate and multivariate analyses for early risk of stroke, myocardial infarction, and death were performed, considering the influence of age, sex, comorbidities, clinical symptoms, and anatomic features. Results The cumulative 30-day stroke and death rate was 1.2%. A total of 10 strokes occurred and resulted in three deaths. The postoperative stroke risk was significantly higher in the subgroup of patients treated for symptomatic carotid artery disease: 2,6% ( P = 0,004). Univariate analysis and logistic regression did not show statistical significance for 30-day results in any of the considered variables. Conclusion Patients with significant medical comorbidities, contralateral carotid occlusion, and high carotid lesions can undergo surgery without increased complications. Those parameters should not be used as exclusion criteria for CEA.

Background To study the incidence, the types, and the results of secondary procedures performed after endovascular treatment of infrarenal abdominal aortic aneurysm (AAA). To compare the population of patients who underwent secondary procedure (P2) with the population of those who did not require it. Material and Methods Between 1998 and 2008, this study included all the patients electively treated for AAA with stentgrafts that were still available on the market on January 1, 2009. Data were prospectively collected and retrospectively analyzed. The postoperative follow-up included at least a systematic computed tomography scan at 6, 12, 18, and 24 months and then every year. P2 were defined as any additionnal procedures performed to treat aneurysm related complications after initial stentgraft implantation. Results We studied 162 patients with a mean 40 ± 31 months’ follow-up. In 32 patients (19.7%), there were 46 P2, 3 of them were surgical conversion and 1 with endovascular conversion. Thirty-nine P2 were scheduled, and seven were performed in emergency. Nine patients underwent more than one P2. P2 was indicated for type II endoleak in 17 cases, 13 of them with a diameter increase; for type I endoleak in 10 cases; for AAA rupture in 3 cases; for occlusion or stentgraft stenosis in 13 cases; and for 1 type III endoleak, 1 endotension, and 1 femoro-femoral crossover bypass infection. Two ruptures occurred in patients who had undergone P2. The immediate technical success was 89.1%. At 30 days, morbidity was 10.9%, and there was no mortality. Survival rates at 3 and 5 years were respectively 85.2% and 71.9% in patients with secondary procedure and 70.6% and 47.5% in the others ( p = 0.046). Conclusions In patients treated for AAA with second generation stentgrafts, in the long term, secondary procedure rate was 19.7%. Survival rate for patients who underwent a secondary procedure was better, which was probably related to the fact that they were younger at the time of stentgraft implantation. Large AAA diameter was a secondary-procedure risk factor.

International audience; Usual imaging after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm (AAA) consists of AAA diameter monitoring and endoleak detection. Among additional predictor parameters previously proposed to help clinicians in better identifying subgroups of AAA still at risk of rupture, AAA wall motion after EVAR has been studied, but its value was not clearly established. Tissue Doppler imaging (TDI) is an ultrasonographic modality which allows wall motion measurements along an arterial segment. The aim of the current study was to analyze AAA wall motion with TDI before and after EVAR and to describe its evolution in patients with more than 1 month of follow-up. Twenty-five consecutive patients undergoing EVAR between February 2005 and June 2007 gave informed consent to be prospectively investigated with the TDI system before EVAR and at each visit during follow-up. The mean (SD) follow-up was 13.7 (9.7) months. Maximum mean segmental dilation (MMSD), segmental compliance, dilation at maximum diameter, pressure strain elastic modulus (Ep), and stiffness were compared between three periods (before stenting, before discharge, and at last follow-up), and their relation with AAA diameter was analyzed. A significant decrease in AAA compliance was immediately observed after successful EVAR and remained stable during later follow-up. On the other hand, AAA diameter progressively decreased along time and was statistically lower at the last control compared to the initial value. MMSD, segmental compliance, and dilation at maximum diameter were positively related to AAA diameter. This means that the larger the AAA diameter after stenting, the higher the value for these parameters can be expected. On the contrary, percentage of AAA diameter decrease and percentage of MMSD decrease were not related after successful EVAR. There was no parallelism between loss in compliance and diameter decrease along time, and there is not a unique pattern of AAA diameter and compliance evolution after EVAR. Even if comparison between patients without and with endoleak was weak due to the small sample of the latter group (five patients with endoleak), compliance tended to be greater in case of endoleak. AAA wall motion after successful EVAR reflects complex interactions between all the components of the stented aneurysm which evolve over time, including true compliance of the aneurysm wall itself; intra-aneurysm sac pressure with possible different effects for peak, mean, and pulse pressures; remodeling of the thrombus; stiffness characteristics of the graft; and systemic pressure. Combining simultaneous MMSD records with actual intrasaccular pressure measurements in patients with and without endoleak would improve our understanding of the clinical pulsatility mechanism within AAA after EVAR.