Giant aortic arch aneurysm in elderly patient

Here we present you a Type II of Crawford classification aortic aneurysm. Our patient 89-year-old woman with history of hypertension, diabetes mellitus, smoking habits and polyposis of descending/sigmoid colon came to our attention for rectorrhagia, asthenia, dyspnoea and dizziness. A computer tomography exam revealed an aortic arch aneurysm, aortic ectasia at a level of aortic hiatus and infra-renal aortic aneurysmal dilation.In accord to aortic team meeting and patient decision, to refer this lady to medical therapy instead to surgery/hybrid treatment for age patient, comorbidities and high mortality relates to intervention. Aortic arch pathologies are unusual and their treatment is challenging.The aetiology of aortic arch diseases is congenital, chronic, post traumatic, inflammatory, infectious, mechanical and anastomotic, but most frequently is degenerative. Furthermore, the improvement in diagnostic imaging and the aging populations, aortic arch aneurysms have increasingly diagnosed.The incidence of aortic arch diseases is 10-11% and many patients were asymptomatic. Otherwise, many patients came to hospital with catastrophic, life-threatening events and urgent treatment is required. Despite the progress and new technologies have produced new therapeutic options for both cardiac and vascular surgeons is important to highlight the primary role of the aortic team, an interdisciplinary assessment, to find the best tailored treatment, both in acute and chronic setting, for the interest of each patient

Time dependent analysis of concrete structures with variable structural system

A integral relationship is presented for the immediate computation of the function governing the structural system change problem

Creep in continuous composite beams. Part I: Theoretical treatment

Continuous composite beams under statical and geometrical axternal actions are investigated

Approximate calculation methods for solving problems of structures subjected to structural system changes

After presenting the solutions to the problem of heterogeneous structures subject to changes of their structural system, obtained with the use of the main approximate methods, the reliability of the results is examined to compare these with those obtained with the application of the numerical step-by-step procedures of the General Method

Creep in continuous composite beams. Part II: Parametric study

A parametric analysis is performed for continuous composite beams showing the creep effects

Algebraic methods for time-dependent analysis of composite beams

The algebraic viscoelastic methoda are applied for composite beams with flexible shear connector

Homogeneous structures subjected to successive structural system changes -

A viscoelastic analysis of structures subjected to successive structural system chages is performed

Time-dependent Analysis of Prestressed Composite Beams

none3The viscoelastic analysis of composite steel-concrete continuous beams, with prestressed slab and flexible shear connectors, is presented. Two prestressing systems, involving the application of prestressing forces before or after the connection of the concrete slab to the steel beam, are considered. The mathematical formulation of the problem involves internal compatibility equations between beam and slab and between slab and prestressing cables. Such conditions are formulated taking into account the integral-type creep law for the concrete slab. With the model proposed, some relevant examples were investigated and discussed. Partial longitudinal prestressing of the slab, performed using cable with length less than the whole structure, is also analyzed. Particular attention is paid to examining the ''primary'' and the ''secondary'' effects of the prestressing, and the shear force distribution at beam-slab interface. A parametric study is then performed by varying the stiffness of shear connectors and the combining time between slab and beam.L. DEZI;G. LEONI;A. M. TARANTINODezi, Luigino; G., Leoni; A. M., Tarantin

Creep and shrinkage analysis of composite beams

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Viscoelastic heterogeneous structures with variable structural system

The effects of the viscoelastic heterogeneities on structures under successive structural system changes are investigated