Troponin I/ejection fraction ratio: A new index to differentiate Takotsubo cardiomyopathy from myocardial infarction

– Transient hypokinesis, akinesis, or dyskinesis of the left ventricular mid-segments with or without apical involvement; the regional wall motion abnormalities extend beyond a single epicardial vascular distribution; a stressful trigger is often, but not always, present; – Absence of obstructive coronary disease or angiographic evidence of acute plaque rupture; – New ECG abnormalities (either ST-segment elevation and/or T wave inversion) or modest elevation in cardiac troponin; and – Absence of pheochromocytoma or myocarditis.

Optimal design of steel frames accounting for buckling

A formulation of a special design problem devoted to elastic perfectly plastic steel frame structures subjected to different combinations of static and dynamic loads is presented. In particular, a minimum volume design problem formulation is presented and the structure is designed to be able to elastically behave for the assigned fixed loads, to elastically shakedown in presence of serviceability load conditions and to prevent the instantaneous collapse for suitably chosen combinations of fixed and ultimate seismic loadings as well as of fixed and wind actions. The actions that the structure must suffer are evaluated by making reference to the actual Italian seismic code. The dynamic respon…

Bòvedas tabicadas: experimental and numerical analysis

A class of thin vaults, the so-called “bovedas tabicadas”, which represent one of the most common Spanish traditional building techniques at the end of XIX century are studied here, treating the relevant analysis problem through a numerical, as well as an experimental, approach. At first the problem is studied by searching for the behaviour of the material effecting suitable experiments. Once the constitutive behaviour of the materials and the structural elements are experimentally characterized, a semi inverse method for the identification of the optimum mechanical parameters to assign to an equivalent homogeneous ideal material through analysis reproducing the executed experimental tests …

Multicriterion design of frames with constraints on buckling

The present paper is devoted to the optimal design of frame structures subjected to static and dynamic loading assuming the material behaviour as elastic perfectly plastic. The relevant optimal design problem is formulated as a minimum volume search problem. The minimum volume structure is determined under suitable constraints on the design variables as well as accounting for different resistance limits: the elastic shakedown limit and the instantaneous collapse limit, considering for each limit condition suitably chosen amplified load combinations. The effects of the dynamic actions are studied on the grounds of the dynamic features of the structure taking into account the structural perio…

Computational methods for optimal shakedown design of FE structures

The paper concerns the optimal shakedown design of structures discretized by elastic perfectly plastic finite elements. The design problem is formulated in four alternative versions, i.e. as the search for the minimum volume design whose shakedown limit load multiplier is assigned or as the search for the maximum shakedown limit load multiplier design whose volume is assigned; both problems are approached on the grounds of the shakedown lower bound and upper bound theorems. Correspondingly four computational methods, one for each original problem, are presented. These methods consist in solving iteratively new problems which are simpler than the original ones, but expressed in such a way th…

EFFECT OF CANREONATE PLUS ANGIOTENSIN-CONVERTING ENZYME INHIBITORS VERSUS ANGIOTENSIN-CONVERTNG ENZYME INHIBITORS AOLNE ON SYSTOLIC AND DIASTOLIC FUNCTION IN PATIENTS WITH ACUTE ANTERIOR MYOCARDIAL INFARCTION

delayed facilitated percutaneous coronary intervention versus immediate in reperfused stemi

Sul progetto di telai metallici ad elevata dissipazione plastica

A bilateral convergent bounding technique for plastic deformations

For the class of elastic perfectly plastic discrete structures, subjected to a dynamic loading history, a bilateral bounding technique for plastic deformations has been studied. The computation of the bound is founded on the concept that to obtain it, any history of fictitious plastic deformations can be used, if only admissible. Such history is obtained by solving a sequence of linear programming problems (LPPs) with a multiple step compared to the step of the sequence of the quadratic programming problems (QPPs) adopting in the classic elasto-plastic analysis. The constraints of the LPPs coincide with the constraints of the QPPs, while the objective function is a linear combination of var…

Comparison of Ivabradine Versus Metoprolol in Early Phases of Reperfused Anterior Myocardial Infarction With Impaired Left Ventricular Function: Preliminary Findings

BACKGROUND: beta-blockers in ST-segment elevation myocardial infarction (STEMI) are indicated for patients without a contraindication, particularly in patients with high heart rates (HR) or blood pressures. Epidemiological studies have shown that elevated HR represents a risk factor for cardiovascular morbidity. The study investigates the feasibility, tolerability, and the effects after 30 days of follow-up of ivabradine (IVA) versus metoprolol (METO) in early phases of anterior STEMI reperfused by percutaneous coronary intervention (PCI). METHODS AND RESULTS: Patients with a first anterior STEMI, Killip class I-II, an acceptable echocardiographic window, and admitted within 4hours of the o…

Optimal design of structures equipped with different seismic protecting devices

Analisi numerica e sperimentale sul comportamento meccanico delle volte catalane

P-Delta effect in structural optimization

The present paper is devoted to the optimal design of structures constituted by elastic perfectly plastic material. In particular, reference will be made to the minimum volume design of multi-storey steel frames taking into account the P-Delta effect. For the sake of generality, the structure is thought as discretized into compatible finite elements and subjected to fixed and quasi-statically acting (wind) loads as well as to dynamic (seismic) loads. The effects of the dynamic actions are studied by utilizing a classical modal technique. The relevant optimal design problem is formulated on the grounds of a statical approach and different resistance limits are considered: in particular, it i…

Effects of canrenoate plus angiotensin-converting enzyme inhibitors versus angiotensin-converting enzyme inhibitors alone on systolic and diastolic function in patients with acute anterior myocardial infarction

Background Aldosterone (ALDO) exerts profibrotic effects, acting via the mineralocorticoid receptors in cardiovascular tissues. Aldosterone antagonism in combination with angiotensin-converting enzyme inhibition may better protect against the untoward effects of ALDO than angiotensin-converting enzyme inhibition alone. Methods In a double-blind randomized study, the tolerability and efficacy of canrenoate (25 mg/d) plus captopril versus captopril alone were evaluated in 510 patients with an acute anterior myocardial infarction (MI), a serum creatinine concentration 5.5 mEq/L and creatinine levels to >2.0 mg/L after 10 days of treatment were observed. At 180 days, the mitral E-wave–A-wave ra…

G-protein-coupled receptor kinase 5 polymorphism and Takotsubo cardiomyopathy.

BACKGROUND: Takotsubo cardiomyopathy (TTC) is an increasingly reported clinical syndrome that mimics acute myocardial infarction without obstructive coronary artery disease and is characterized by transient systolic dysfunction of the apical and/or mid-segments of the left ventricle. The syndrome mainly occurs in postmenopausal women with high adrenergic state conditions. Nowadays, the pathophysiology of TTC is not yet known and the possibility of a genetic predisposition is controversial. AIMS: The purpose of this study was to assess the genetic susceptibility to TTC through analysis of the L41Q polymorphism of the G-protein-coupled receptor kinase 5 (GRK5). METHODS AND RESULTS: In a cohor…

Reply to letter by Parodi et al. regarding article: Revised clinical diagnostic criteria for Takotsubo syndrome: The Takotsubo Italian Network proposal.

Combination of indomethacin and statin compared with indomethacin and placebo in patients with a first episode of acute pericarditis: preliminary findings

The aim of the present study was to evaluate the safety and efficacy of the combination of indomethacin and statin compared with indomethacin plus placebo in patients with a first episode of pericarditis. A total of 55 consecutive patients with acute pericarditis were randomized in a double-blind manner into two groups: group I (statin group) was treated with 150 mg of indomethacin plus 10 mg of rosuvastatin, and group 2 (placebo group) was treated with 150 mg of indomethacin plus placebo. Both groups received treatment up to the normalization of inflammation markers and for the following week. Clinical and laboratory assessments [white cell count, ESR (erythrocyte sedimentation rate) and C…

Shakedown design of structures under dynamic loading

The optimal (minimum volume) design of elastic plastic structures under static and dynamic loads is studied. The minimum volume design is reached accounting for different resistance limits: it is required that the optimal structure simultaneously satisfies the elastic shakedown limit and the instantaneous collapse limit, or alternatively the elastic and the plastic shakedown limits, adopting for each limit condition a suitably chosen load combination and some appropriate load amplifiers. The load combinations are characterized by the presence of fixed loads, quasi-statical cyclic loads and dynamic (seismic) loads. Reference is made to the Italian Code related to structural analysis and desi…

Analisi limite elastica di strutture con resistenze aleatorie sotto azioni dinamiche campionate

Bounds on plastic deformations for structures in plastic shakedown

Optimal design of structures under dynamic loading

Climatic variables in Takotsubo cardiomyopathy: role of temperature

Background Recent studies documented a seasonal (summer) and circadian (morning) temporal distribution of takotsubo cardiomyopathy (TTC). Aim The aim of our study was to investigate whether there is a relationship among season, temperature and the occurrence of TTC. A second aim of our study was the comparison of climatic variables in Takotsubo cardiomyopathy versus acute myocardial infarction (AMI). Methods We enrolled consecutive patients with TTC in three Italian centres and, for comparison consecutive patients with AMI. The frequency of TTC and AMI patients according to month, season and quartiles of temperature (I quartile: 9.8–15-, II quartile: 15–19-, III quartile: 19–25- and IV quar…

Is delayed facilitated percutaneous coronary intervention better than immediate in reperfused myocardial infarction? Six months follow up findings

Background: There are several new strategies proposed to improve the outcome of patients with ST-elevation myocardial infarction (STEMI). One approach is the resurgent use of facilitated percutaneous coronary interventions (PCI). Until recently, deciding whether immediate PCI after combined treatment (facilitated PCI) is more appropriate than delayed PCI (short time) has not been investigated. The aim of this study, therefore, was to investigate the outcomes in patients initially successfully treated pharmacologically and immediate PCI < 2 hr, and in patients initially successfully treated with pharmacological therapy and with delayed PCI (12–72 h). Methods: 451 reperfused STEMI patients, a…

On the analysis of Catalan thin vaults

This paper is concerned with the identification, modelling and analysis of thin layered vaults, typical in the Catalan constructions of the XIX century. These special structures, also known as bovedas tabicadas, are characterized by very low thickness with respect to the medium surface dimensions and by the presence of different superimposed layers of bricks tied with mortar, are studied in order to individuate a coherent mechanical model for describing the material behaviour, to recognize the structural response utilizing as comparison adequate experimental results, and to extend the obtained results for the analysis of new vaults or for the restoration design of existing vaults. Firstly, …

An optimal design of FE structures with limited ductility

The minimum volume design of elastic perfectly plastic FE structures subjected to quasi-static fixed and cyclic loads is searched in such a way that the structure remains into the elastic field in serviceability conditions, while it is subjected to alternating plasticity under very strong cyclic actions, incremental and instantaneous collapse being prevented. In order to take into account the limited ductility of the material, suitable chosen limits on the plastic deformations related to the initial transient phase and/or to the subsequent steady-state phase are considered for the structure subjected to very strong cyclic actions. A numerical application confirm the theoretical expectations…

A plastic shakedown design of FE structures with constraints on deformations

Bounds on transient phase plastic deformations in optimal design of steel frames subjected to cyclic loads

A minimum volume multicriterion design of elastic perfectly plastic steel frames subjected to a combination of quasi-static fixed and cyclic loads, bounding the transient phase plastic deformations, is proposed. The problem is formulated according to a plastic shakedown criterion, so that incremental and instantaneous collapse are certainly prevented when the frame is subjected to very strongly amplified cyclic loads. The further condition that the structure must also behave elastically in serviceability conditions is imposed. Since the steady-state loading history is known it is possible to directly bound the steady-state plastic deformations. By applying a suitable own bounding theorem, i…

An Optimal Design Formulation according to some limited Ductility Behaviour

Shakedown design of frames with constraints on deformations

Delayed facilitated percutaneous coronary intervention is better than immediate in reperfused myocardial infarction

Optimum design of structures with limited ductility

Optimality conditions for shakedown design of trusses

This paper deals with optimal shakedown design of truss structures constituted by elastic perfectly plastic material. The design problem is formulated by means of a statical approach on the grounds of the shakedown lower bound theorem, and by means of a kinematical approach on the grounds of the shakedown upper bound theorem. In both cases two different types of design problem are formulated: one searches for the minimum volume design whose shakedown limit load is assigned; the other searches for the maximum shakedown limit load design whose volume is assigned. The Kuhn-Tucker equations of the four problems here above mentioned are found by utilizing a variational approach; these equations …

Reply to letter by Parodi et al. regarding article: Revised clinical diagnostic criteria for Tako-tsubo syndrome: The Tako-tsubo Italian Network proposal.

Immediate versus delayed facilitated percutaneous coronary intervention. A pilot study

The study was aimed to investigate the outcomes in patients initially successfully treated pharmacologically and immediate PCI <2 hours, and in patients initially successfully treated with pharmacological therapy and delayed PCI (12-72 hours). All patients had to have successful reperfusion, to receive the combination of a standard abciximab infusion plus half dose rtPA. Similar results were observed in both groups. Delayed PCI group showed a favorable trend in restenosis and bleedings (ns) and a significant reduced angiographic evidence of thrombus formation in IRA. Our very preliminary data suggest the safety and possible use of delayed facilitated PCI in patients with STEMI. The studied …

Discrete Structure Shakedown Design Ices ’95, Hawai, July 30 – August 3, 1995

The minimum volume shakedown design problem was already approached by several authors with studies devoted to discrete structures (see e.g. [1]–[5]) and to continuous structures (see e.g. [6]). Except some very simple structural typologies, also the optimal shakedown design problem formulations for continuous structures need to be discretized in the application stage. In any case, the relevant optimal shakedown design problem for discrete (or discretized) structures is formulated in terms of design variables as well as behavioural variables, and consists in the search for the/a minimum volume design among all feasible designs (i.e. able to shakedown). Due to its strong non-linearity, the la…

A multicriterion design of steel frames with shakedown constraints

The minimum volume design of elastic perfectly plastic steel frames subjected to fixed and cyclic loads is searched in such a way that the structure remains in elastic field in serviceability conditions, while it is subjected to alternating plasticity under very strong cyclic actions, incremental and instantaneous collapse being prevented. The problem is faced on the grounds of a statical and a kinematical approach. The Kuhn-Tucker conditions of the two problems prove that they are each one the dual of the other and provide useful pieces of information about the structural behaviour. Numerical applications confirm the theoretical expectations: optimal designs turn out to be quite light, wit…

An Approximate Technique for Dynamic Elastic-Plastic Analysis

The possibility of obtaining an approximate sufficiently reliable response for elasticplastic discretized structures subjected to dynamic load (kinematical and/or mechanical), with alow computational effort, has been considered. A suitable technique to this effect comes from the form of the dynamic influence matrix of imposed plastic strains on self-stresses, which is shaped by adding up a sparse time-dependent matrix and a block diagonal time-independent matrix (which is the sum of two block diagonal matrices). Several cases of practical interest have been studied, among these cases a special one where all the degrees-of-freedom are dynamic. The technique is compared to other approximate t…

The indirect force method

Abstract It is known that the matrix force method shows some advantages over the displacement method for certain classes of problems, particularly in optimization and in the stress concentration analysis. Notwithstanding this, few efforts have been made to employ this method in engineering problems. In this paper, within the elastic analysis of frames and trusses, the indirect force method, utilizing beam-node type finite elements, is proposed. This method is based on the kinematical and mechanical study of nodes and of beams, the latter connected with the nodes by their first extremes according to a preliminary arrangement. In this formulation kinematical singularities are included, in the…

On the structural optimization in presence of base isolating devices

The minimum volume design of plane frames constituted by elastic perfectly plastic material and subjected to appropriate combinations of fixed, cyclic and dynamic loads is studied. The influence on the design, in terms of cost (volume) and behavioural features, of seismic protecting devices is particularly focused. The considered protecting device is a lead rubber bearing base isolation system. Two optimal design problem formulations are proposed for the structure with or without the protecting device, both based on the so-called statical approach. The minimum volume frame is reached accounting for three different resistance limits: the purely elastic limit, the (elastic) shakedown limit an…

Progetto ad adattamento plastico di strutture ad elementi finiti

Safety and tolerability of abciximab in patients with acute myocardial infarction and failed thrombolysis.

Abstract Aim: The aim of this study was to evaluate glycoprotein IIb/IIIa receptor inhibitor effectiveness in AMI patients with unsuccessful thrombolysis. Methods: Eighty-four patients hospitalised within 4 h of symptom onset were randomised (single blind) into two groups. Regardless of the group, placebo or GP IIb/IIIa inhibitors were administered to patients who did not present with reperfusion signs 30 min after starting thrombolysis and 30–60 min after the end of full thrombolysis in patients with pain recurrence and ST-segment elevation. Reperfusion was assessed by the creatine kinase peak occurring within 12 h, by the observation of rapid ST-segment reduction (50–70% within 1 h) in 12…

An Iterative Approach to Dynamic Elastic-Plastic Analysis

The step-by-step analysis of structures constituted by elastic-plastic finite elements, subjected to an assigned loading history, is here considered. The structure may possess dynamic and/or not dynamic degrees-of-freedom. As it is well-known, at each step of analysis the solution of a linear complementarity problem is required. An iterative method devoted to solving the relevant linear complementarity problem is presented. It is based on the recursive solution of a linear complementarity, problem in which the constraint matrix is block-diagonal and deduced from the matrix of the original linear complementarity problem. The convergence of the procedure is also proved. Some particular cases …

Effects of Administration of Glycoprotein IIb/IIIa Receptor Antagonists in Patients with Failed Thrombolysis

Aim To evaluate the effectiveness of glycoprotein (GP) IIb/IIIa receptor antagonists in patients with acute myocardial infarction (AMI) who have undergone unsuccessful thrombolysis.

Relationship between ACE-DD polymorphism and diastolic performance in healthy subjects.

Background—The ACE-D allele has been associated with cardiovascular disease. The study evaluates the relationship between the ACE-ID genotypes and diastolic function in healthy subjects after 6 years of follow-up. Methods—Two hundred and seventy-five healthy volunteers aged 25–55 years had normal physical examination, 12-lead ECG, acceptable echocardiographic windows and echocardiogram at entry. Venous blood was drawn for DNA analysis. Results—Two hundred and forty-two subjects completed 6 years of follow-up. Three genetically distinct groups were obtained: ACE-DD group (n=71, 26F/45M, mean age 48±7 years); ACE-ID (n=115, 39F/76M, mean age 40±7 years); and ACE-II (n=56, 20F/36M, mean age 47…

An optimal design of elastic plastic structures with bounds on transient and steady-state plastic deformations

Computational procedures for plastic shakedown design of structures

The minimum volume design problem of elastic perfectly plastic finite element structures subjected to a combination of fixed and perfect cyclic loads is studied. The design problem is formulated in such a way that incremental collapse is certainly prevented. The search for the structural design with the required limit behaviour is effected following two different formulations, both developed on the grounds of a statical approach: the first one operates below the elastic shakedown limit and is able to provide a suboptimal design; the second one operates above the elastic shakedown limit and is able to provide the/an optimal design. The Kuhn–Tucker conditions of the two problems provide usefu…

Characteristics of coronary microcirculatory function in patients with Takotsubo syndrome.

Background: Takotsubo syndrome (TS) is a recently described cardiac syndrome whose pathogenesis is still unclear. We investigated the characteristics of coronary microcirculatory function in patients with TS through the analysis of the TIMI frame count (TFC) compared to normal subjects and with to subjects with microvascular angina (MA). Methods: We enrolled 71 TS patients (F:M =69:2, mean age of 65.27±9.53 years), 70 controls (F:M =34:36, mean age of 56.63±13.5 years) and 71 patients with MA, (F:M =69:2, mean age of 65.9±9.2 years). The assessment of the microcirculation was carried out through the TFC. Results: microcirculation was significantly altered in patients with TS compared with h…

Bounds on plastic strains for elastic plastic structures in plastic shakedown conditions

The problem related to the computation of bounds on plastic deformations for structures in plastic shakedown condition (alternating plasticity) is studied. In particular, reference is made to structures discretized by finite elements constituted by elastic perfectly plastic material and subjected to a special combination of fixed and cyclic loads. The load history is known during the steady-state phase, but it is unknown during the previous transient phase; so, as a consequence, it is not possible to know the complete elastic plastic structural response. The interest is therefore focused on the computation of bounds on suitable measures of the plastic strain which characterizes just the fir…

Elastic/plastic shakedown load boundary determination accounting for limited ductility structures

The problem related to the determination of the borderline between elastic/plastic shakedown and incremental/instantaneous collapse domains in the Bree diagramfor elastic perfectly plastic structures subkected to a combination of fixed and perfect cyclic load is studied. The relevant boundary is determined taking into account suitable limits related to the structures ductility features. In particular, basing on a special bounding theorem, it is possible to introduce appropriate boundary constraints on chosen measure of the plastic strains occurring at the end of the transient phase of the structural response

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Optimal Bounds on Plastic Deformations for Bodies Constituted of Temperature-Dependent Elastic Hardening Material

Bounds are investigated on the plastic deformations in a continuous solid body produced during the transient phase by cyclic loading not exceeding the shakedown limit. The constitutive model employs internal variables to describe temperature-dependent elastic-plastic material response with hardening. A deformation bounding theorem is proved. Bounds turn out to depend on some fictitious self-stresses and mechanical internal variables evaluated in the whole structure. An optimization problem, aimed to make the bound most stringent, is formulated. The Euler-Lagrange equations related to this last problem are deduced and they show that the relevant optimal bound has a local character, i.e., it …

Progetto ottimale di strutture discrete con vincoli sulla deformazione plastica

Elastic plastic analysis iterative solution

The step-by-step analysis of finite element elastic plastic structures subjected to an assigned (quasi-static) loading history, is considered; it identifies with the well-known sequence of linear complementarity problems. An iterative technique devoted to solve the relevant linear complementarity problem is presented. It is based on the recursive solution of a suitable linear complementarity problem, deduced from the relevant one and easier than it. The procedure convergency is proved. Some noticing particular cases are examined. The physical meaning of the procedure is shown to be a plastic relaxation. The suitable numerical ranges for some check parameter values, to be utilized in the app…