Search results for "Cardiac"
showing 10 items of 1495 documents
Carbon dioxide levels during pre-hospital active compression–decompression versus standard cardiopulmonary resuscitation
1998
Abstract In a prospective randomised study we investigated end-tidal carbon dioxide levels during standard versus active compression–decompression (ACD) cardiopulmonary resuscitation (CPR) assuming that the end-tital carbon dioxide reflects cardiac output during resuscitation. In each group 60 patients with out-of-hospital cardiac arrest were treated either with the standard or the ACD method. End-tidal CO 2 ( p et CO 2 , mmHg) was assessed with a side-stream capnometer following intubation and then every 2 min up to 10 min or restoration of spontaneous circulation (ROSC). There was no difference in p et CO 2 between both patient groups. However, CO 2 was significantly higher in patients wh…
Der Schlaganfall als medizinischer Notfall
1999
Studies into the pathophysiology of acute ischaemic stroke have indicated that treatment options are likely to be optimised when early signs of stroke are recognised and treatment is initiated within 3 hours from symptom onset. For most patients there is a long delay between the onset of symptoms and the start of therapy. Many factors are responsible for this time delay: signs and symptoms often go unrecognised by patients, relatives and bystanders and stroke is not given a high priority by medical staff. Although a small number of stroke patients is treated as emergency and attended to by the emergency medical services within this time window, this number could easily be increased by inten…
Numerical Simulations of the Hydrodynamics of the Abdominal Aorta Aneurysm (AAA) Using a Smoothed Particle Hydrodynamics Code with Deformable Wall Pr…
2018
We present some preliminary results of the numerical simulations of the hydrodynamic characteristics of an abdominal aorta aneurysm (AAA) patient specific test case. Images of the AAA lumen have been acquired in 10 discrete time-steps through a stabilized cardiac cycle by electrocardiogram-gated computer tomography angiography, and are used to approximate the in vivo, time dependent kinematic fields of the (internal) arterial wall. The flow field is simulated by a Smoothed Particle SPH numerical model, where the kinematics of the boundary of the computational domain (the internal aortic vessel) is the one computed by the above procedure. The outputs of the SPH model, i.e., pressure and flow…
Three-dimensional cardiac computational modelling: methods, features and applications
2015
[EN] The combination of computational models and biophysical simulations can help to interpret an array of experimental data and contribute to the understanding, diagnosis and treatment of complex diseases such as cardiac arrhythmias. For this reason, three-dimensional (3D) cardiac computational modelling is currently a rising field of research. The advance of medical imaging technology over the last decades has allowed the evolution from generic to patient-specific 3D cardiac models that faithfully represent the anatomy and different cardiac features of a given alive subject. Here we analyse sixty representative 3D cardiac computational models developed and published during the last fifty …
New epicardial mapping electrode with warming/cooling function for experimental electrophysiology studies
2010
Cardiac electrical activity is influenced by temperature. In experimental models, the induction of hypothermia and/or hyperthermia has been used for the study of mechanisms of cardiac arrhythmia. A system that allows for localized, controlled induction, besides simultaneously recording electrical activity in the same induced area, needs to be developed ad hoc. This article describes the construction and application of a new system capable of locally modifying the epicardial temperature of isolated hearts and of carrying out cardiac mapping with sufficient spatial resolution. The system is based on a thermoelectric refrigerator and an array of 128 stainless steel unipolar electrodes in encap…
Myocardial Infarction Quantification from Late Gadolinium Enhancement MRI Using Top-Hat Transforms and Neural Networks
2019
Significance: Late gadolinium enhanced magnetic resonance imaging (LGE-MRI) is the gold standard technique for myocardial viability assessment. Although the technique accurately reflects the damaged tissue, there is no clinical standard for quantifying myocardial infarction (MI), demanding most algorithms to be expert dependent. Objectives and Methods: In this work a new automatic method for MI quantification from LGE-MRI is proposed. Our novel segmentation approach is devised for accurately detecting not only hyper-enhanced lesions, but also microvascular-obstructed areas. Moreover, it includes a myocardial disease detection step which extends the algorithm for working under healthy scans.…
Long Term Results After Repair of Type A Acute Aortic Dissection According to False Lumen Patency.
2009
Background. Late survival and freedom from retreatment on the descending aorta was evaluated after ascending aortic repair for type A acute aortic dissection (TAAAD). Methods. Between March 1992 and January 2006, 189 TAAAD patients (mean age, 52 11; range, 17 to 83 years) were included; of these, 58 had a patent false lumen, and 49 had Marfan syndrome. The descending aorta was evaluated postoperatively with computed tomography (CT). Late outcomes were assessed by Cox regression analysis and actuarial survival and freedom from retreatment by the Kaplan-Meier method. Mean follow-up was 88 44 months. Results. There were 38 (20%) late deaths. At 10 years, survival was 89.8% 2.1% for patients wi…
Arsenic trioxide alters the differentiation of mouse embryonic stem cell into cardiomyocytes
2015
AbstractChronic arsenic exposure is associated with increased morbidity and mortality for cardiovascular diseases. Arsenic increases myocardial infarction mortality in young adulthood, suggesting that exposure during foetal life correlates with cardiac alterations emerging later. Here, we investigated the mechanisms of arsenic trioxide (ATO) cardiomyocytes disruption during their differentiation from mouse embryonic stem cells. Throughout 15 days of differentiation in the presence of ATO (0.1, 0.5, 1.0 μM) we analysed: the expression of i) marker genes of mesoderm (day 4), myofibrillogenic commitment (day 7) and post-natal-like cardiomyocytes (day 15); ii) sarcomeric proteins and their orga…
Synchrony Analysis of Unipolar Cardiac Mapping during Ventricular Fibrillation
2014
Ventricular Fibrillation (VF) is one of the main causes of death in developed countries. Recent studies have shown that fibrillation have a complex organization scheme. This work uses three measures of synchrony to characterize three groups of rabbit hearts. These groups consist of rabbits trained with physical exercise (N=7), untrained rabbits treated with a drug (N=13) and a control group of untrained rabbits (N=15). Cardiac mapping records were acquired using a 240-electrode array placed on left ventricle of isolated rabbit hearts, and VF was induced pacing at increasing rates. Two acquisitions were performed: maintained perfusion, and ischemic damage produced by an artery ligation. The …
Analysis of the Modifications in the Spectral and Morphologic Regularity during Ventricular Fibrillation Produced by Physical Exercise and the Use of…
2015
Chronic physical exercise modifies cardiac activity improving response to malignant arrhythmia and, specifically, ventricular fibrillation (VF). Drug administration as glibenclamide, responsible for K + ATP channel blocking, is also generating a positive response against fibrillation.