Serwis Infona wykorzystuje pliki cookies (ciasteczka). Są to wartości tekstowe, zapamiętywane przez przeglądarkę na urządzeniu użytkownika. Nasz serwis ma dostęp do tych wartości oraz wykorzystuje je do zapamiętania danych dotyczących użytkownika, takich jak np. ustawienia (typu widok ekranu, wybór języka interfejsu), zapamiętanie zalogowania. Korzystanie z serwisu Infona oznacza zgodę na zapis informacji i ich wykorzystanie dla celów korzytania z serwisu. Więcej informacji można znaleźć w Polityce prywatności oraz Regulaminie serwisu. Zamknięcie tego okienka potwierdza zapoznanie się z informacją o plikach cookies, akceptację polityki prywatności i regulaminu oraz sposobu wykorzystywania plików cookies w serwisie. Możesz zmienić ustawienia obsługi cookies w swojej przeglądarce.
The results of study on T-wave alternans in the group of patients with ischemic heart disease are shown. The body surface potential maps were recorded with use of 67 channel high-resolution ECG system. Electrocardiographic stress test was performed during the patient examinations. The T-wave alternans ratio was calculated and results were compared with data obtained by single-photon emission computed...
The conventional spectral method is indeed a typical confidence interval computation that use normalized Fourier transform frequencies F{f} at f = 0.5. In order to get a robust detector with respect to spikes due to single-frequency tone interference and to exploit the entire frequency band to reduce the variance we proposed new parameter called SMM (F{0.5}/median(F{]0.5, 0[})). The second stage of...
Stress tests are typical protocols that exhibit T waves changes for healthy and ischemic subjects. ST-T elevation is one example among others that characterizes ischemic patient. A more complex description of T wave changes needs extended models with a cost of higher identification pitfalls. We propose here to work in the inverse normalized integrals domain. This domain permits us an estimation of...
Vectorcardiographic representation of T-wave alternans (TWA) has been presented in new coordinate system created by means of singular value decomposition where the first axis was in T-loop direction and other axes were perpendicular. Projection of T-loop vector on the plane perpendicular to the first axis was analyzed. The study shows that in case of healthy people and those with detectable TWA, in...
The benefits of higher efficiency are clearly evident, both in reducing energy costs and increasing load capacity when limited by thermal constraints. There is also the impact on the global environment and reduction in growth rate of energy. HE technologies, if broadly adopted could have a substantial impact. If was assume that the average savings to a carrier is 5% across their network and that their...
The aim of the study was to assess the relations between QRST and STT, QRS integral maps in three groups: healthy volunteers, patients without arrhythmia and patients with implanted cardioverter-defibrillator (ICD). The obtained results showed that the mean correlation coefficient between STT and QRST integral maps was highest in the group of healthy subjects while the mean correlation coefficient...
The aim of the study was a selection of best ECG leads to get the significant T-wave alternans signal (TWA). The group of 16 patients with implantable cardioverter-defibrillator (ICD) was examined. The 64 lead ECG system was used. Three lead sets were analyzed: 64 BSPM lead set, orthogonal lead set (XYZ) and standard 12 lead set. Patients were divided into two groups: TWA positive (TWA(+)) 5 patients...
In this work a simulation study of T-wave alternans is proposed in order to determine the ability of TWA detectors to quantify the performance characteristics in terms of amplitude estimation accuracy. ECG signals were simulated by repeating a single beat, and by adding four types of noise each at two different levels of power. TWA episodes with different amplitudes and waveforms were added to the...
Podaj zakres dat dla filtrowania wyświetlonych wyników. Możesz podać datę początkową, końcową lub obie daty. Daty możesz wpisać ręcznie lub wybrać za pomocą kalendarza.