43 research outputs found
Embolic strokes of undetermined source: prevalence and patient features in the ESUS Global Registry
Background:
Recent evidence supports that most non-lacunar cryptogenic strokes are embolic. Accordingly, these strokes have been designated as embolic strokes of undetermined source (ESUS).
Aims:
We undertook an international survey to characterize the frequency and clinical features of ESUS patients across global regions.
Methods:
Consecutive patients hospitalized for ischemic stroke were retrospectively surveyed from 19 stroke research centers in 19 different countries to collect patients meeting criteria for ESUS.
Results:
Of 2144 patients with recent ischemic stroke, 351 (16%, 95% CI 15% to 18%) met ESUS criteria, similar across global regions (range 16% to 21%), and an additional 308 (14%) patients had incomplete evaluation required for ESUS diagnosis. The mean age of ESUS patients (62 years; SDâ=â15) was significantly lower than the 1793 non-ESUS ischemic stroke patients (68 years, pââ€â0.001). Excluding patients with atrial fibrillation (nâ=â590, mean ageâ=â75 years), the mean age of the remaining 1203 non-ESUS ischemic stroke patients was 64 years (pâ=â0.02 vs. ESUS patients). Among ESUS patients, hypertension, diabetes, and prior stroke were present in 64%, 25%, and 17%, respectively. Median NIHSS score was 4 (interquartile range 2â8). At discharge, 90% of ESUS patients received antiplatelet therapy and 7% received anticoagulation.
Conclusions:
This cross-sectional global sample of patients with recent ischemic stroke shows that one-sixth met criteria for ESUS, with additional ESUS patients likely among those with incomplete diagnostic investigation. ESUS patients were relatively young with mild strokes. Antiplatelet therapy was the standard antithrombotic therapy for secondary stroke prevention in all global regions
Global survey of the frequency of atrial fibrillation-associated stroke: embolic stroke of undetermined source global registry
Background and PurposeâAtrial fibrillation (AF) is increasingly recognized as the single most important cause of disabling ischemic stroke in the elderly. We undertook an international survey to characterize the frequency of AF-associated stroke, methods of AF detection, and patient features.
MethodsâConsecutive patients hospitalized for ischemic stroke in 2013 to 2014 were surveyed from 19 stroke research centers in 19 different countries. Data were analyzed by global regions and World Bank income levels.
ResultsâOf 2144 patients with ischemic stroke, 590 (28%; 95% confidence interval, 25.6â29.5) had AF-associated stroke, with highest frequencies in North America (35%) and Europe (33%) and lowest in Latin America (17%). Most had a history of AF before stroke (15%) or newly detected AF on electrocardiography (10%); only 2% of patients with ischemic stroke had unsuspected AF detected by poststroke cardiac rhythm monitoring. The mean age and 30-day mortality rate of patients with AF-associated stroke (75 years; SD, 11.5 years; 10%; 95% confidence interval, 7.6â12.6, respectively) were substantially higher than those of patients without AF (64 years; SD, 15.58 years; 4%; 95% confidence interval, 3.3â5.4; P<0.001 for both comparisons). There was a strong positive correlation between the mean age and the frequency of AF (r=0.76; P=0.0002).
ConclusionsâThis cross-sectional global sample of patients with recent ischemic stroke shows a substantial frequency of AF-associated stroke throughout the world in proportion to the mean age of the stroke population. Most AF is identified by history or electrocardiography; the yield of conventional short-duration cardiac rhythm monitoring is relatively low. Patients with AF-associated stroke were typically elderly (>75 years old) and more often women
Drug utilization patterns and reported health status in ethnic German migrants (Aussiedler) in Germany: a cross-sectional study
Measurement of the cosmic ray spectrum above eV using inclined events detected with the Pierre Auger Observatory
A measurement of the cosmic-ray spectrum for energies exceeding
eV is presented, which is based on the analysis of showers
with zenith angles greater than detected with the Pierre Auger
Observatory between 1 January 2004 and 31 December 2013. The measured spectrum
confirms a flux suppression at the highest energies. Above
eV, the "ankle", the flux can be described by a power law with
index followed by
a smooth suppression region. For the energy () at which the
spectral flux has fallen to one-half of its extrapolated value in the absence
of suppression, we find
eV.Comment: Replaced with published version. Added journal reference and DO
Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory
The Auger Engineering Radio Array (AERA) is part of the Pierre Auger
Observatory and is used to detect the radio emission of cosmic-ray air showers.
These observations are compared to the data of the surface detector stations of
the Observatory, which provide well-calibrated information on the cosmic-ray
energies and arrival directions. The response of the radio stations in the 30
to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of
the incoming electric field. For the latter, the energy deposit per area is
determined from the radio pulses at each observer position and is interpolated
using a two-dimensional function that takes into account signal asymmetries due
to interference between the geomagnetic and charge-excess emission components.
The spatial integral over the signal distribution gives a direct measurement of
the energy transferred from the primary cosmic ray into radio emission in the
AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air
shower arriving perpendicularly to the geomagnetic field. This radiation energy
-- corrected for geometrical effects -- is used as a cosmic-ray energy
estimator. Performing an absolute energy calibration against the
surface-detector information, we observe that this radio-energy estimator
scales quadratically with the cosmic-ray energy as expected for coherent
emission. We find an energy resolution of the radio reconstruction of 22% for
the data set and 17% for a high-quality subset containing only events with at
least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO
Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy
We measure the energy emitted by extensive air showers in the form of radio
emission in the frequency range from 30 to 80 MHz. Exploiting the accurate
energy scale of the Pierre Auger Observatory, we obtain a radiation energy of
15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV
arriving perpendicularly to a geomagnetic field of 0.24 G, scaling
quadratically with the cosmic-ray energy. A comparison with predictions from
state-of-the-art first-principle calculations shows agreement with our
measurement. The radiation energy provides direct access to the calorimetric
energy in the electromagnetic cascade of extensive air showers. Comparison with
our result thus allows the direct calibration of any cosmic-ray radio detector
against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI.
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Coronary artery calcifications in the long-term follow-up of Kawasaki disease
To determine if detection of coronary artery calcifications in patients with Kawasaki disease may serve as a noninvasive predictor of future coronary artery events.
A prospective, cohort pilot study that included 18 patients with Kawasaki disease >1 year from the acute disease was performed including 9 patients with coronary abnormalities during the acute illness (Group 1) and 9 without coronary abnormalities (Group 2). Patients were classified by echocardiography as having none, resolved, or residual coronary artery abnormalities. Electron beam computed tomography (EBCT) scans were completed using the Agatson coronary calcium scoring system. Intermediate follow-up was performed 2.5 years after EBCT to determine if clinically significant coronary artery events (myocardial infarction or sudden death) had occurred.
Late echocardiographic abnormalities corresponded with the early echocardiographic abnormalities in 5 of 9 patients (
P = .029) in Group 1. The late echocardiographic abnormalities significantly correlated with detection of calcifications by EBCT in 4 of 5 patients (95% CI 28%-99%). One patient with residual coronary abnormalities and coronary artery calcifications with the highest calcium score subsequently had a sudden death. Detection of coronary artery calcifications may be predictive of sudden death (
P = .056). No residual echocardiographic abnormalities, coronary artery calcifications, or coronary artery events occurred in Group 2 patients.
Patients with Kawasaki disease with residual coronary abnormalities show EBCT evidence of coronary artery calcifications. Detection of coronary artery calcifications may be useful for risk stratification in the long-term management of patients with Kawasaki disease