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Upper limb loss alters individuals’ private and professional life. Prosthetic devices are thus a solution to supply the missing upper limb segments. Nevertheless, commercial prostheses are often unaffordable, or inaccessible, to underprivileged individuals (e.g., no health insurance, low incomes, warzone). Among potential affordable alternatives, additive manufacturing, commonly “3D printing”, has been increasingly employed. This technology offers higher availability and accessibility, and can produce complex geometrical and highly customized products, which are essential features for prostheses manufacturing. Therefore, this study aims to portray an overview of reliable open-source upper limb 3D-printed prostheses currently available. We thus searched the scientific literature and online repositories hosting 3D-printable designs. We extracted data relative to mechanical and kinematic properties, 3D printing process and efficacy for each device. We found six studies implementing open-source 3DP upper limb prostheses and twenty-five open-source designs from online databases meeting selection criteria. Devices’ technical specifications were not systematically reported. In conclusion, though open-source 3D-printed upper limb prostheses can perform some functional tasks and grasps, and are widely employed to supply limb differences, further research is mandatory to validate their usage and to prove their clinical efficacy. More guidelines are required to unify contributions from private makers and non-governmental organizations with scientific groups.

OBJECTIVES: Our goal was to assess the aortic leaflet free margin length (FML) and geometric height (gH) in a normal aortic valve (AV), aorta dilatation and aortic leaflet prolapse. METHODS: We measured the FML and gH intraoperatively in 132 patients operated on for aortic insufficiency, aortic dilatation, endocarditis or fibroelastoma. Patients were divided into 3 groups: normal tricuspid AV (group 1, n = 12), aortic dilatation (group 2, tricuspid = 43, bicuspid = 18) and leaflet prolapse (group 3, tricuspid = 32, bicuspid = 27). The FML and gH were compared between the groups and between the leaflets within each group. RESULTS: In a normal tricuspid AV, the mean FML and gH were 34.7 ± 3.1 mm and 18.8 ± 1.7 mm, respectively. In group 2 tricuspid, the FML and gH were greater than those in group 1 (FML 43.7 ± 4.4, P < 0.001; gH 21.2 ± 1.8, P = 0.003). In group 3, tricuspid, the FML of the prolapsing leaflet was greater than the FML of the non-prolapsing leaflet (48.3 ± 5.4 vs 42.2 ± 3.6; P < 0.001). In group 2, bicuspid, FML of both leaflets were similar in group 2, but augmented on the fused leaflet compared to the non-fused leaflet in group 3 (fused 55.4 ± 6.3; non-fused 46.2 ± 6.2; P < 0.001). In groups 2 and 3 bicuspid, the gH of the non-fused leaflet was systematically greater than the fused leaflet (group 2 non-fused 24.6 ± 2.5 vs fused 20.4 ± 2.1; P < 0.001). CONCLUSIONS: In aortic dilatation and leaflet prolapse, FML and, to a lesser extent, gH increased significantly compared to those of normal AV function. FML and gH dimensions also depended on the valve configuration (tricuspid/bicuspid). These data provide new insight into the pathomorphology of AV disease and will serve to further develop new methods of AV repair based on intraoperative measurements of the FML.

In the originally published version of this article there was some unclear syntax in the first sentence of the Conclusions of the Abstract, which should read: In aortic dilatation and leaflet prolapse, FML and, to a lesser extent, gH increased significantly compared to those of normal AV function. This has now been corrected.

Glutaraldehyde fixed xenogeneic heart valve prosthesis are hindered by calcification and lack of growth potential. The aim of tissue decellularization is to remove tissue antigenicity, avoiding the use of glutaraldehyde and improve valve integration with low inflammation and host cell recolonization. In this preliminary study, we investigated the efficacy of a NaOH-based process for decellularization and biocompatibility improvement of porcine pulmonary heart valves in comparison to a detergent-based process (SDS-SDC0, 5%). Native cryopreserved porcine pulmonary heart valves were treated with detergent and NaOH-based processes. Decellularization was assessed by Hematoxylin and eosin/DAPI/alpha-gal/SLA-I staining and DNA quantification of native and processed leaflets, walls and muscles. Elongation stress test investigated mechanical integrity of leaflets and walls (n = 3 tests/valve component) of valves in the native and treated groups (n = 4/group). Biochemical integrity (collagen/elastin/glycosaminoglycans content) of leaflet-wall and muscle of the valves (n = 4/group) was assessed and compared between groups with trichrome staining (Sirius Red/Miller/Alcian blue). Secondly, a preliminary in vivo study assessed biocompatibility (CD3 and CD68 immunostaining) and remodeling (Hematoxylin and eosin/CD31 and ASMA immunofluorescent staining) of NaOH processed valves implanted in orthotopic position in young Landrace pigs, at 1 (n = 1) and 3 months (n = 2). Decellularization was better achieved with the NaOH-based process (92% vs 69% DNA reduction in the wall). Both treatments did not significantly alter mechanical properties. The detergent-based process induced a significant loss of glycosaminoglycans (p < 0,05). In vivo, explanted valves exhibited normal morphology without any sign of graft dilatation, degeneration or rejection. Low inflammation was noticed at one and three months follow-up (1,8 +/- 3,03 and 0,9836 +/- 1,3605 CD3 cells/0,12 mm in the leaflets). In one

OBJECTIVES: Aortic cusp free margins are a central target in most aortic valve repair operations to optimize valve coaptation. The objective of this anatomical study was to analyse the normal dimensions of free margin length (FML) and coaptation surface and to analyse their relationship with other valve and root dimensions in normal tricuspid aortic valves. METHODS: We analysed 25 aortic root homografts. Eight valve and root measurements were obtained from fresh specimens including the length of the free margin while applying appropriate tension on the structures. The valves were then fixed with formalin in the diastolic position under pressure to allow measurement of the coaptation surface. In addition to normal values, we analysed the correlations and ratios between the different measures. RESULTS: The mean FML was 34.3 ± 3.1 mm. The FML was similar between the 3 cusps and correlated with all other valve and root measures. The ratio of the FML to the geometric height was 1.81, and the free edge length/sinotubular junction was 1.29. The mean coaptation surface was 122 ± 21 mm2 per cusp and corresponded to 41% of the cusp surface. The central coaptation length was 3.3 ± 0.8 mm, and the lateral coaptation length was 5.9 ± 0.6 mm. The total coaptation surface per specimen was 184 ± 32 mm2. CONCLUSIONS: We described the normal dimensions of the FML and coaptation surface in the tricuspid aortic valve. These measurements will serve in the further development of an objective method of free margin shortening based on intraoperative measurements of the FML to treat cusp prolapse and low coaptation after valve-sparing surgery.

Ce papier se situe dans le cadre de la conception d'un dispositif chirurgical en cardiologie destiné à la découpe circulaire de la valve aortique. Ici, les conséquences d'une mauvaise utilisabilité du dispositif peuvent être graves mais il est impossible de réaliser des tests utilisateurs pour chaque itération de conception. Les auteurs présentent les méthodes qu'ils ont appliquées pour contourner l’évaluation en situation réelle et pour aménager l'utilisabilité d'un prototype. L’intérêt des méthodes (inspection heuristique, modélisation de la tâche et test en situation artificielle) relève de leurs utilisations combinées. Globalement, les résultats tendent à montrer que la triangulation de méthode est vraiment intéressante si elle croise des méthodes de collecte de données artificielles et réelles, avec l’utilisateur et sans l’utilisateur.

Provided is an instrument (100) for gauging a free margin (420) length (FML) of a heart valve cusp (410) in a vessel (416) comprising a gauging head (200) having a proximal (20) and distal end (40) comprising a body (210) having a prising member (212) at the distal (40) end adapted to be received within a cusp pocket (428) of the heart valve cusp and which extends in a proximal (20) direction to form a gauging member (220) of a fixed and defined length (L) adapted to abut the free margin (420), wherein the gauging member (220) comprises at either end a contact probe (222-a, 222-b) spaced apart by the fixed and defined length (L) and adapted to abut a vessel wall where the free margin edges attach.

A device (100) is presented for excision of a heart valve comprising a first (120) and second (140) clamping element in mutual sliding relation, each having an annular clamping surface (122, 142) which annular clamping surfaces (122, 142) mutually co-operate to form an annular clamping region (166) configured for clamping a heart valve annularly, and a slidable cutting element (160) slidable and rotatable with respect to the annular clamping region (166) configured to circularly excise the heart valve, wherein the slidable cutting element (160) is displaceable within an annulus of the annular clamping zone region (166).

Glutaraldehyde preservation is the gold standard for cardiovascular biological prosthesis. However, secondary calcifications and the absence of tissue growth remain major limitations. Our study assessed in vitro and in vivo the biocompatibility of human (fascia lata, pericardium) and porcine tissues (pericardium, peritoneum) treated with a physicochemical procedure for decellularization and non-conventional pathogens inactivation. Biopsies were performed before and after treatment to assess decellularization (HE/Dapi staining/DNA quantification/MHC I/alpha gal immunostaining) and mechanical integrity. Forty-five rats received an abdominal aortic patch of native cryopreserved tissues (n = 20), treated tissues (n = 20) or glutaraldehyde-preserved bovine pericardium (GBP, control, n = 5). Grafts were explanted at 4 weeks and processed for HE/von Kossa staining and immunohistochemistries for lymphocytes (CD3)/macrophages (CD68) histomorphometry. 95% of decellularization was obtained for all tissues except for fascia lata (75%). Mechanical properties were slightly altered. In the in vivo model, a significant increase of CD3 and CD68 infiltrations was found in native and control implants in comparison with decellularized tissues (p < 0.05). Calcifications were found in 3 controls. Decellularized tissues were recolonized. GBP showed the most inflammatory response. This physicochemical treatment improves the biocompatibility of selected xeno/allogeneic tissues in comparison with their respective native cryopreserved tissues and with GBP. Incomplete decellularization is associated with a significantly higher inflammatory response. Our treatment is a promising tool in the field of tissue decellularization and tissue banking.

The increase of life expectancy in Western countries over the past 30 years has resulted in an exponential increase of elderly patients presenting for cardiac surgery. In this population, aortic stenosis is the most important acquired heart disease, with a prevalence of 4.8% in patients aged over 75 years. Despite the good results with conventional aortic valve replacement in elderly patients, many patients are denied surgery because of the high operative risk. In this frail population, transcatheter aortic valve implantation (TAVI) can be a good compromise to achieve good results and minimize morbidity and mortality. This technique allows the implantation of an expandable bioprosthesis without the resection of the native aortic valve. Several complications have been described as a consequence of the residual highly calcified valve being squeezed between the aortic wall and the stent of the implant. To avoid those complications, it is necessary to resect the aortic valve before TAVI. Starting from the initial need asked by the surgeon – design a device for minimally invasive aortic valve resection – this thesis firstly focuses on a detailed study of the heart, the pathology of calcific aortic stenosis and its different current medical treatments. The clarification of the task starts with the analysis of the need and the functional analysis of the need leading to the establishment of the functional specifications. Then, the choices for the different function from the functional specifications are performed. The conception of the different subsets of the solution follows a traditional design method, until the realization of demonstrators. A clinical trial on patients undergoing open heart surgery ends this work and validates the concept of the final solution. Finally, some prospects are given to improve the device before its marketing thanks to the results achieved throughout this work., (FSA - Sciences de l'ingénieur) -- UCL, 2016

Transcatheter aortic valve implantation was introduced into clinical practice in 2002 as a rescue approach in patients presenting with symptomatic severe aortic stenosis but not eligible for conventional aortic valve replacement. This technique allows implantation of a balloon expandable bioprosthesis without resection of the native aortic valve. Several complications are described as a consequence of the residual highly calcified valve being squeezed against the aortic wall by the stent of the implant. This can result in deformation of the metal stent and paravalvular leakage, risk of occlusion of the coronary ostia, or central and peripheral embolization of valvular debris. To avoid these complications, many authors suggest the possibility to resect and remove the native aortic valve before transcatheter aortic valve implantation. In this field, different authors have described possible techniques and different sources of energy to resect the calcified valve. In this article, we review the development of these experimental techniques and discuss future prospects in this field.

L'atelier vise à offrir participants de vivre une expérience d’activité de sensibilisation au travail en équipe. Cette activité peut s’organiser pour un très grand nombre de participants. Il s’agit de résoudre une mission situation-problème en équipe. Elle permet de développer des compétences transversales liées au travail en équipe et propose par la suite de réaliser un bilan critique sur le fonctionnement en équipe.

Le travail en groupe et la communication sont des compétences indispensables à la pratique du métier d’ingénieur. Dès la 1ère année, les étudiants ingénieurs de l'Ecole Polytechnique de Louvain (EPL) doivent adopter des méthodes de travail collectif en vue de développer des compétences ad hoc. Cet article présente une expérience menée en début de curriculum.