89 research outputs found
Beyond periodic revivals for linear dispersive PDEs
We study the phenomenon of revivals for the linear Schr\"odinger and Airy
equations over a finite interval, by considering several types of non-periodic
boundary conditions. In contrast with the case of the linear Schr\"odinger
equation examined recently (which we develop further), we prove that,
remarkably, the Airy equation does not generally exhibit revivals even for
boundary conditions very close to periodic. We also describe a new, weaker form
of revival phenomena, present in the case of certain Robin-type boundary
conditions for the linear Schr\"odinger equation. In this weak revival, the
dichotomy between the behaviour of the solution at rational and irrational
times persists, but in contrast with the classical periodic case, the solution
is not given by a finite superposition of copies of the initial condition.Comment: 26 pages, 8 figures, typos corrected, main results moved to the
introduction, reduced size of the figure
Comparative study of efficiency on prototype against generic drugs on lipid lowering agents
The purpose of the current study is to approve or disprove the efficiency of the effectiveness comparing generic drugs and the respectively prototype drugs on lipid lowering agents based on two specific quality factors; first the thickness of the vessels' endothelium and second the calcification on vessels' walls. For the study drugs where recognized and divided into two categories: Unique drugs which included prototype drugs with protected exclusivity of the use of the active substance (on patent) according to the law. And generic drugs which NOM has given approvals as generic drugs
Heart disease in patients with haemoglobinopathies
Hereditary hemoglobin disorders, also termed haemoglobinopathies, include mainly beta -thalasszemia and sickle cell disease and represent the most common monogenic disorders in human. Cardiac complications are still a leading cause of mortality and morbidity in patients with haemoglobinopathy, although heart disease due to either severe anaemia or iron overload have dramatically reduced in patient populations receiving modern regular therapy and follow-up. The spectrum of cardiovascular manifestations in haemoglobinopathies is wide and includes ventricular dysfunction, pulmonary hypertension, pericarditis-myocarditis, arrhythmias stroke and thromboembolic events..
New Revival Phenomena for Bidirectional Dispersive Hyperbolic Equations
In this paper, the dispersive revival and fractalization phenomena for
bidirectional dispersive equations on a bounded interval subject to periodic
boundary conditions and discontinuous initial profiles are investigated.
Firstly, we study the periodic initial-boundary value problem of the linear
beam equation with step function initial data, and analyze the manifestation of
the revival phenomenon for the corresponding solution at rational times. Next,
we extend the investigation to periodic initial-boundary value problems of more
general bidirectional dispersive equations. We prove that, if the initial
functions are of bounded variation, the dynamical evolution of such periodic
problems depend essentially upon the large wave number asymptotics of the
associated dispersion relations. Integral polynomial or asymptotically integral
polynomial dispersion relations produce dispersive revival/fractalization
rational/irrational dichotomies, whereas those with non-polynomial growth
result in fractal profiles at all times. Finally, numerical experiments, in the
concrete case of the nonlinear beam equation, are used to demonstrate how such
effects persist into the nonlinear regime.Comment: 28 pages, 11 figure
Social determinants of health in pulmonary embolism management and outcome in hospitals: Insights from the United States nationwide inpatient sample
BACKGROUND
The role of social determinants in the treatment and course of acute pulmonary embolism (PE) is understudied.
OBJECTIVE
To investigate the association between social determinants of health with in-hospital management and early clinical outcomes following acute PE.
METHODS
We identified hospitalizations of adults with acute PE discharge diagnosis from the nationwide inpatient sample (2016-2018). Multivariable regression was used to investigate the association between race/ethnicity, type of expected primary payer, and income with the use of advanced PE therapies (thrombolysis, catheter-directed treatment, surgical embolectomy, extracorporeal membrane oxygenation), length of stay, hospitalization charges, and in-hospital death.
RESULTS
A total of 1,124,204 hospitalizations with a PE diagnosis were estimated from the 2016-2018 nationwide inpatient sample, corresponding to a hospitalization rate of 14.9/10,000 adult persons-year. The use of advanced therapies was lower in Black and Asian/Pacific Islander (vs. White patients: adjusted odds ratio [OR], 0.87; 95% confidence interval [CI], 0.81-0.92 and OR 0.76; 95% CI, 0.59-0.98) and in Medicare- or Medicaid-insured (vs. privately-insured; OR, 0.73; 95% CI, 0.69-0.77 and OR, 0.68; 95% CI, 0.63-0.74), although they had the greatest length of stay and hospitalization charges. In-hospital mortality was higher in the lowest income quartile (vs. highest quartile; OR, 1.09; 95% CI, 1.02-1.17). Among high-risk PE, patients of other than the White race had the highest in-hospital mortality.
CONCLUSION
We observed inequalities in advanced therapies used for acute PE and higher in-hospital mortality in races other than White. Low socioeconomic status was also associated with lesser use of advanced treatment modalities and greater in-hospital mortality. Future studies should further explore and consider the long-term impact of social inequities in PE management
Cost-of-Illness Analysis of Long-Term Health Care Resource Use and Disease Burden in Patients With Pulmonary Embolism: Insights From the PREFER in VTE Registry
Background As mortality from pulmonary embolism (PE) decreases, the personal and societal costs among survivors are receiving increasing attention. Detailing this burden would support an efficient public health resource allocation. We aimed to provide estimates for the economic and disease burden of PE also accounting for long-term health care use and both direct and indirect costs beyond the acute phase. Methods and Results This is a cost-of-illness analysis with a bottom-up approach based on data from the PREFER in VTE registry (Prevention of Thromboembolic Events-European Registry in Venous Thromboembolism). We calculated direct (clinical events and anticoagulation) and indirect costs (loss of productivity) of an acute PE event and its 12-month follow-up in 2020 Euros. We estimated a disability weight for the 12-month post-PE status and corresponding disability adjusted life years presumably owing to PE. Disease-specific costs in the first year of follow-up after an incident PE case ranged between 9135 Euros and 10 620 Euros. The proportion of indirect costs was 42% to 49% of total costs. Costs were lowest in patients with ongoing cancer, mainly because productivity loss was less evident in this already burdened population. The calculated disability weight for survivors who were cancer free 12 months post-PE was 0.017, and the estimated disability adjusted life years per incident case were 1.17. Conclusions The economic burden imposed by PE to society and affected patients is considerable, and productivity loss is its main driver. The disease burden from PE is remarkable and translates to the loss of roughly 1.2 years of healthy life per incident PE case
Contemporary role of cardiac magnetic resonance in the management of patients with suspected or known coronary artery disease
Cardiac magnetic resonance imaging (CMR) is a useful non-invasive radiation-free imaging modality for the management of patients with coronary artery disease (CAD). CMR cine imaging provides the “gold standard” assessment of ventricular function, late gadolinium enhancement (LGE) provides useful data for the diagnosis and extent of myocardial scar and viability, while stress imaging is an established technique for the detection of myocardial perfusion defects indicating ischemia. Beyond its role in the diagnosis of CAD, CMR allows accurate risk stratification of patients with established CAD. This review aims to summarize the data regarding the role of CMR in the contemporary management of patients with suspected or known coronary artery disease
Cardiopulmonary exercise testing during follow-up after acute pulmonary embolism
BACKGROUND
Cardiopulmonary exercise testing (CPET) may provide prognostically valuable information during follow-up after pulmonary embolism (PE). Our objective was to investigate the association of patterns and degree of exercise limitation, as assessed by CPET, with clinical, echocardiographic and laboratory abnormalities and quality of life (QoL) after PE.
METHODS
In a prospective cohort study of unselected consecutive all-comers with PE, survivors of the index acute event underwent 3- and 12-month follow-ups, including CPET. We defined cardiopulmonary limitation as ventilatory inefficiency or insufficient cardiocirculatory reserve. Deconditioning was defined as peak O uptake (V' ) <80% with no other abnormality.
RESULTS
Overall, 396 patients were included. At 3 months, prevalence of cardiopulmonary limitation and deconditioning was 50.1% (34.7% mild/moderate; 15.4% severe) and 12.1%, respectively; at 12 months, it was 44.8% (29.1% mild/moderate; 15.7% severe) and 14.9%, respectively. Cardiopulmonary limitation and its severity were associated with age (OR per decade 2.05, 95% CI 1.65-2.55), history of chronic lung disease (OR 2.72, 95% CI 1.06-6.97), smoking (OR 5.87, 95% CI 2.44-14.15) and intermediate- or high-risk acute PE (OR 4.36, 95% CI 1.92-9.94). Severe cardiopulmonary limitation at 3 months was associated with the prospectively defined, combined clinical-haemodynamic end-point of "post-PE impairment" (OR 6.40, 95% CI 2.35-18.45) and with poor disease-specific and generic health-related QoL.
CONCLUSIONS
Abnormal exercise capacity of cardiopulmonary origin is frequent after PE, being associated with clinical and haemodynamic impairment as well as long-term QoL reduction. CPET can be considered for selected patients with persisting symptoms after acute PE to identify candidates for closer follow-up and possible therapeutic interventions
Awareness of venous thromboembolism among patients with cancer: Preliminary findings from a global initiative for World Thrombosis Day
BACKGROUND
Cancer-associated venous thromboembolism (CAT) has detrimental impact on patients' clinical outcomes and quality of life. Data on CAT education, communication, and awareness among the general cancer population are scanty.
METHODS
We present the preliminary results of an ongoing patient-centered survey including 27 items covering major spheres of CAT. The survey, available in 14 languages, was promoted and disseminated online through social networks, email newsletters, websites, and media.
RESULTS
As of September 20, 2022, 749 participants from 27 countries completed the survey. Overall, 61.8% (n = 460) of responders were not aware of their risk of CAT. Among those who received information on CAT, 26.2% (n = 56) were informed only at the time of CAT diagnosis. Over two thirds (69.1%, n = 501) of participants received no education on signs and symptoms of venous thromboembolism (VTE); among those who were educated about the possible clinical manifestations, 58.9% (n = 119) were given instructions to seek consultation in case of VTE suspicion. Two hundred twenty-four respondents (30.9%) had a chance to discuss the potential use of primary thromboprophylaxis with health-care providers. Just over half (58.7%, n = 309) were unaware of the risks of bleeding associated with anticoagulation, despite being involved in anticoagulant-related discussions or exposed to anticoagulants. Most responders (85%, n = 612) valued receiving CAT education as highly relevant; however, 51.7% (n = 375) expressed concerns about insufficient time spent and clarity of education received.
CONCLUSIONS
This ongoing survey involving cancer patients with diverse ethnic, cultural, and geographical backgrounds highlights important patient knowledge gaps. These findings warrant urgent interventions to improve education and awareness, and reduce CAT burden
A pragmatic approach to the use of inotropes for the management of acute and advanced heart failure: An expert panel consensus
Inotropes aim at increasing cardiac output by enhancing cardiac contractility. They constitute the third pharmacological pillar in the treatment of patients with decompensated heart failure, the other two being diuretics and vasodilators. Three classes of parenterally administered inotropes are currently indicated for decompensated heart failure, (i) the beta adrenergic agonists, including dopamine and dobutamine and also the catecholamines epinephrine and norepinephrine, (ii) the phosphodiesterase III inhibitor milrinone and (iii) the calcium sensitizer levosimendan. These three families of drugs share some pharmacologic traits, but differ profoundly in many of their pleiotropic effects. Identifying the patients in need of inotropic support and selecting the proper inotrope in each case remain challenging. The present consensus, derived by a panel meeting of experts from 21 countries, aims at addressing this very issue in the setting of both acute and advanced heart failure. (C) 2019 The Authors. Published by Elsevier B.V.Peer reviewe
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