Isolated supradiaphragmatic descending thoracic aorta stenosis in a Takayasu's disease: Surgical cure

A 21-year-old male patient presented with a typical middle aortic syndrome. Echography disclosed a severe narrowing of the lower thoracic aorta with parietal thickening. The isolated character of the lesion was confirmed by magnetic resonance imaging and aortography. The surgical cure was realized by a Dacron bypass between the upper thoracic descending aorta and the juxta-diaphragmatic thoracic aorta. Aortic biopsy confirmed Takayasu's disease. Postoperative course was uneventful with normalized blood pressure. The therapeutic options, surgery versus percutaneous dilatation and stent, are discussed. Copyright © 2001 Elsevier Science B.V.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Aortic valve aneurysm after acute endocarditis

Endocarditis at the aortic level is usually characterized by the presence of a vegetation or an abscess on echocardiography. This paper reports on what is believed by the authors to be the first case of endocarditis presenting as an aneurysmal deformation of one aortic cusp without a vegetation.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Ascending aorta syphilitic aneurysm presenting as a dystrophic disease

A 37-year-old female originating from Central Africa presented with cardiac failure, aortic insufficiency and aortic root dilatation of supposed dystrophic origin. Left coronary ostial dilatation and dense adhesions between the aorta and the pulmonary trunk at operation were the only unusual features. However, pathological examination evoked a syphilitic disease and serology confirmed luetic infection. The diagnosis and the therapeutic approach are discussed. Syphilitic aneurysms belong to the protohistory of vascular surgery (1), but, in the antibiotherapy era, tracking a syphilitic aneurysm is like fishing for coelacanth. When this pathology mimics a dystrophic aneurysm, diagnosis and therapeutic attitude becomes hazardous and justifies the present report.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Prolonged cardiac arrest treated by emergency closed chest cardiopulmonary bypass in a patient with suspected amphetamine cardiomyopathy

Organized by the Belgian Society of Intensive Care and Emergency Medicineinfo:eu-repo/semantics/nonPublishe

Gallium nitride MEMS resonators: how residual stress impacts design and performances

International audienceStarting from Gallium Nitride epitaxially grown on silicon, pre-stressed micro-resonators with integrated piezoelectric transducers have been designed, fabricated, and characterized. In clamped-clamped beams, it is well known that tensile stress can be used to increase the resonant frequency. Here we calculate the mode shape functions of out-of-plane flexural modes in pre-stressed beams and we derive a model to predict both the resonant frequency and the piezoelectric actuation factor. We show that a good agreement between theory and experimental results can be obtained and we derive the optimal design for the electromechanical transduction. Finally, our model predicts an increase of the quality factor due to the tensile stress, which is confirmed by experimental measurements under vacuum. This study demonstrates how to take advantage from the material quality and initial stress resulting of the epitaxial process