Second look Holter ECG in neurorehabilitation Knecht, Stefan; Petsch, Sebastian; Kirchhof, Paulus ...
Neurological research and practice,
12/2019, Volume:
1, Issue:
1
Journal Article
Peer reviewed
Open access
Many stroke survivors suffer recurrent stroke because paroxysmal atrial fibrillation (AF) was missed and no preventive anticoagulation initiated. This prospective cohort study determined the added ...diagnostic yield of second-look 24-h electrocardiographic recording (ECG) in a population at high risk for AF: patients who suffered a stroke of such severity that they require inpatient neurorehabilitation.
We enrolled 508 patients with ischemic stroke admitted to post-acute inpatient neurorehabilitation and determined whether AF was detected during acute care at the referring hospital. Second-look baseline and 24-h Holter ECG were then conducted during neurorehabilitation. Primary outcome was number of newly detected AF with duration of > 30 s; secondary outcomes were number of newly detected absolute arrhythmia of 10-30 s and < 10 s duration. For comparison, we further enrolled 100 patients with hemorrhagic stroke without history of AF (age = 72 + 11 years, 51% female).
In 206 of the 508 ischemic stroke patients, AF had been detected during acute phase work-up (age = 78 + 10 years, 55% female). For the remaining 302 ischemic stroke patients, no AF was detected during acute phase work-up (age = 74 + 9 years; 47% female). Second-look 24-h ECG showed previously missed AF of > 30 s in 20 of these patients, i.e. 6.6% of the sample, and shorter absolute arrhythmia in 50 patients (i.e. 16.5%).
Second-look 24-Hour ECG performed during post-acute inpatient neurorehabilitation has a high diagnostic yield and should become a standard component of recurrent stroke prevention.
A liquid‐crystal elastomer (LCE) iris inspired by the human eye is demonstrated. With integrated polyimide‐based platinum heaters, the LCE material is thermally actuated. The radial contraction ...direction, similar to a mammalian iris, is imprinted to the LCE by a custom‐designed magnetic field. Actuation of the device is reproducible over multiple cycles and controllable at intermediate contraction states.
Two major risk factors exist for atrial fibrillation in patients who have had a stroke: age2 and stroke severity.3,4 These two risk factors converge in those patients who require inpatient ...rehabilitation.5 Therefore, a standardised second 24 h Holter-ECG done during inpatient rehabilitation should be considered as an alternative to three...
We demonstrate a tunable imaging system based on the functionality of the mammalian eye using soft-matter micro-optical components. Inspired by the structure of the eye, as well as by the means ...through which nature tunes its optical behavior, we show that the technologies of microsystems engineering and micro-optics may be used to realize a technical imaging system whose biomimetic functionality is entirely distinct from that of conventional optics. The engineered eyeball integrates a deformable elastomeric refractive structure whose shape is mechanically controlled through application of strain using liquid crystal elastomer (LCE) actuators; two forms of tunable iris, one based on optofluidics and the other on LCEs with embedded heaters; a fixed lens arrangement; and a commercial imaging sensor chip. The complete microsystem, optimized to yield optical characteristics close to those of the human eye, represents the first fully functional, soft-matter-based tunable single-aperture eye-like imager.
Microlenses fabricated using flexible elastomers can be tuned in focal length by application of controlled strain. By varying the strain azimuthally, the lenses may be deformed asymmetrically such ...that aberrations may be controlled. This approach is used to tune the astigmatism of the tunable lenses, and it is shown that the generated wavefront may be accurately controlled. The lens presented here has an initial focal length of 32.6 mm and a tuning range of +2.3 mm for approximately 10% applied strain. The range of directly tunable Zernike polynomials representing astigmatism is about 3 µm, while the secondary lens errors, which cannot be tuned directly, vary only by about 0.2 µm.
We demonstrate the combination of a tunable lens and tunable aperture in a compact imaging system whose structure is inspired by the human eye. The concept is based on innovative optical materials ...and tuning mechanisms including an optofluidic iris for a tunable aperture and an elastomer lens for focal length tuning. Wavefront and modulation transfer function analysis reveals a high imaging performance of both the individual elements and the complete system. Most significantly, the wavefront is not degraded (ΔPV<λ/10) when tuning the focal length (Δf=5.36%).
The dreaded effects of climate change have led to a new research focus in many applications. In urban planning, the visualization of carbon footprints has become one of the most sought after aspects. ...Urban planning data of carbon footprints contains spatial (location) and abstract (statistical indicators) information. Although many techniques for the visualization of such partially spatial data have been successfully applied in the area of geovisualization, the core focus has been on a global depiction of non-spatial information. However, conducting local comparisons, as in the case of comparing neighborhood districts and households, is of particular importance in investigative tasks. Additionally, representing different carbon footprint indicators (multiple non-spatial parameters) and unstructured parameter values (resulting in scaling issues) in a static representation provides an interesting challenge for visualization. This paper describes a novel and generic solution to the above-mentioned issues: a neighborhood relation diagram for the local comparison of non-spatial information in partial spatial data. The technique is based on the geometric computation of Voronoi diagrams according to a weighted neighborhood metric. The shape of spatial regions (e.g. city districts) within this diagram is characterized by a directed and constrained deformation according to the non-spatial (i.e. carbon footprint) relations to neighboring regions. The effectiveness of our method is highlighted in a preliminary study of carbon footprint patterns in downtown Phoenix (Arizona, USA). In this study, neighborhood relation diagrams enable city planners to detect local effects on carbon emissions and their relation to planning projects.
This paper presents a novel approach for calculating the carbon footprint in an urban region at the scale of individual neighborhoods. The approach is applied to Maricopa County, Arizona, for two ...different scenarios of growth. Our strategy for monitoring carbon footprints also involves a new form of visualization that goes beyond the two-dimensional thematic maps and provides better representation of multidimensional spatial data. Our monitoring system includes grid-based calculation and visualization of potential carbon dioxide emissions for future years under different policy and behavioral scenarios. To calculate a total carbon footprint value, we designate several varieties of relevant emissions such as housing expenditure and electricity. We develop datasets and models that allow for accurate calculation of the carbon footprint for Maricopa County. We provide emissions information for different types of housing units and compare the results for different future scenarios of household change. Finally, we visualize the results in three-dimensional representations that take into account the multidimensional dataset. We employ an intuitive approach in constructing three-dimensional surfaces of carbon footprints using B-Splines and Bezier techniques. This 3D representation allows for understanding and comparing multidimensional data using transparency, different layers, and superimposition techniques.
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