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Automatic cardiac arrhythmia classification based on hybrid 1-D CNN and Bi-LSTM model

Rahul Jagdeep, Sharma Lakhan Dev

Biocybernetics and Biomedical Engineering

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2022

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Vol. 42, no. 1

312--324

EN

Cardiovascular diseases (CVDs) are a group of heart and blood vessel ailments that can cause chest pain and trouble breathing, especially while active. However, some patients with heart disease have no symptoms and may benefit from screening. Electrocardiogram (ECG) measures electrical activity of the heart using sensors positioned on the skin over the chest, and it can be used for the timely detection of CVDs. This work presents a technique for classification among lethal CVDs like atrial fibrillation (Afib), ventricular fibrillation (Vfib), ventricular tachycardia (Vtec), and normal (N) beats. A novel combination of Stationary wavelet transforms (SWT) and a two-stage median filter with Savitzky–Golay (SG) filter were utilised for pre-processing of the ECG signal followed by segmentation and z-score normalisation process. Next, 1-D six-layers convolutional neural network (1- D CNN) was used for automated and reliable feature extraction. After that, bidirectional long short-term memory (Bi-LSTM) was used in the back end for classification of arrhythmias. The novelty of the present work is the use of 1-D CNN and Bi-LSTM architecture followed by relevant and effective pre-processing of the ECG signal makes this technique accurate and reliable. An accuracy of 99.41 % was achieved using 10-fold cross validation, which is superior to the existing state-of-art methods. Thus, this method presents a noble, accurate, and reliable method for classification of cardiac arrhythmia beats.

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Validation of a new device for photoplethysmographic measurement of multi-site arterial pulse wave velocity

Sondej Tadeusz, Jannasz Iwona, Sieczkowski Krzysztof, Dobrowolski Andrzej, Obiała Karolina, Targowski Tomasz, Olszewski Robert

Biocybernetics and Biomedical Engineering

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2021

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Vol. 41, no. 4

1664--1684

EN

Pulse wave velocity (PWV) is commonly used for assessing arterial stiffness and it is a useful and accurate cardiovascular mortality predictor. Currently, many techniques and devices for PWV measurement are known, but they are usually expensive and require operator experience. One possible solution for PWV measurement is photoplethysmography (PPG), which is convenient, inexpensive and provides continuous PWV results. The aim of this paper is validation of a new device for PPG sensor-based measurement of multisite arterial PWV using a SphygmoCor XCEL (as the reference device) according to the recommendations of the Artery Society Guidelines (ASG). In this study, 108 subjects (56 men and 52 women, 20–91 years in 3 required age groups) were enrolled. The multi-site PWV was simultaneous measured by 7 PPG sensors commonly used in pulse oximetry in clinical settings. These sensors were placed on the forehead, and right and left earlobes, fingers and toes. Pulse transit time (PTT) was measured offline as the difference of time delay between two onsets of the pulse wave determined by the intersecting tangent method. The PWV was calculated by dividing the distance between PPG sensors by PTT. During PPG signals measurement, reference carotid to femoral PWV (cfPWV) was performed with a SphygmoCor XCEL system. The Pearson correlation coefficient (r) between the obtained PWV results was calculated. The Bland-Altman method was used to establish the level of agreement between the two devices. Mean difference (md) and standard deviation (SD) were also calculated. The multi-site PWV was highly correlated with accuracy at the ASG-defined level of ‘‘Acceptable” (md < 1.0 m/s and SD ≤ 1.5 m/s) with cfPWV: forehead - right toe (r = 0.75, md = 0.20, SD = 0.97), forehead - left toe (r = 0.79, md = 0.18, SD = 0.91), right ear - right toe (r = 0.79, md = 0.11, SD = 0.96), left ear - left toe (r = 0.75, md = 0.43, SD = 0.99), right ear - left toe (r = 0.78, md = 0.40, SD = 0.93), left ear - right toe (r = 0.78, md = 0.11, SD = 0.96), right finger - right toe (r = 0.66, md = 0.95, SD = 1.29), left finger - lefttoe (r = 0.67, md = 0.68, SD = 1.35). This study showed that PWV measured with the multisite PPG system, in relation to the obtained numerical values, correlated very well with that measured using the commonly known applanation tonometry method. However, it should be noted, that the measured PWV concerns the central and muscular part of the arterial tree while the cfPWV is only for the central one. The best results were obtained when the proximal PPG sensor was placed on the head (ear or forehead) and the distal PPG sensor on the toe. PPG sensors can be placed in many sites at the same time, which provides greater freedom of their configuration. Multi-site photoplethysmography is an alternative method for PWV measurement and creates new possibilities for the diagnostics of cardiovascular diseases.

3

Zobaczmy to, co niewidoczne, czyli wirtualna symulacja krążenia wieńcowego

Grudzińska E.

Inżynier i Fizyk Medyczny

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2018

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Vol. 7, nr 3

155--156

PL

Za początek rozwoju metod obrazowania przyjmuje się 1895 r., kiedy to Wilhelm Conrad Roentgen odkrył promieniowanie X i wykonał zdjęcia dłoni swojej żony. Od tego czasu następuje nieustanny rozwój obrazowana medycznego. Rozwijane są nowe metody, poprawie ulegają także parametry aparatury medycznej, które powodują, że możemy oglądać obrazy o coraz wyższej jakości. Dzięki temu uzyskujemy większą ilość danych o dużej wartości diagnostycznej. Ale czy poprawa parametrów sprzętu to jedyna droga rozwoju technologicznego obrazowania medycznego?

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Prevalence of obesity among the inhabitants of South Bohemia

Olišarová V., Šedová L., Tóthová V.

Journal of Ecology and Health

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2013

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R. 17, nr 3

148--152

EN

Lifestyle diseases constitute a group of diseases whose prevalence has constantly risen since the 1960s. They are closely associated with lifestyle. The modifiable risk factors that include, for example, eating behaviour, leisure-time activity, physical activity and exposure to stress contribute significantly to that trend. The fact that most of the factors are modifiable underlines the importance of primary and secondary prevention. Overweight, obesity and cardiovascular diseases are diseases that should be paid particular attention. The reason consists in the significant increase in their prevalence and the serious consequences connected with those illnesses. According to the data from the European Health Interview Survey (EHIS), 54% of the adult population of the Czech Republic are overweight. From that number, 17% of the population suffer from obesity [3]. Similar results are presented also by the conclusions of the Health Interview Survey published in January 2011. There is a significant shift in the trend to lower ages [5]. The severity of the consequences of an increasing prevalence of cardiovascular diseases is demonstrated by the fact that every year in the Czech Republic about 600 individuals out of 100 000 inhabitants die as a result of them. That constitutes more than 50% of all deaths [1]. This article draws attention to the results of an investigation carried out within the activities of the Prevention Centre in 2011-2012 that examined a total of 346 people over 18 years of age, 267 of them females and 79 males. The values of blood sugar and cholesterol from peripheral blood, blood pressure, height and weight were observed. Also the BMI value and total amount of body fat were measured using the Omron Body Fat Monitor. This device allows the measuring of the total amount of body fat based on bioelectrical impedance.

PL

Choroby cywilizacyjne stanowią grupę chorób, których częstość występowania od lat 60-tych XX wieku stale wzrasta. Są ściśle powiązane ze stylem życia. Modyfikowalne czynniki ryzyka, które przykładowo obejmują nawyki żywieniowe, sposób spędzania czasu wolnego, aktywność fizyczną i narażenie na stres, w sposób istotny wpływają na ten trend. To, że większość tych czynników jest modyfikowalna, podkreśla znaczenie profilaktyki pierwotnej i wtórnej. Należy zwrócić szczególną uwagę na nadwagę, otyłość i choroby sercowo-naczyniowe. Wynika to z istotnego wzrostu częstości występowania oraz poważnych skutków tych schorzeń. Według danych pochodzących z europejskiego ankietowego badania zdrowia ludności (EHIS), 54% dorosłych mieszkańców Czech ma nadwagę. Co więcej, 17% osób należących do tej grupy cierpi na otyłość [3]. Podobne wyniki przedstawiają także wnioski z ankietowego badania zdrowia ludności opublikowane w styczniu 2011 roku. Trend ten uległ istotnemu przesunięciu w kierunku młodszych grup wiekowych [5]. Powagę skutków wzrastającej częstości występowania chorób sercowo-naczyniowych potwierdza fakt, że co roku w Czechach około 600 na 100.000 mieszkańców umiera w ich rezultacie. Liczba ta stanowi ponad 50% całkowitej liczby zgonów [1]. Niniejszy artykuł zwraca uwagę na wyniki badania przeprowadzonego w ramach działalności Ośrodka Profilaktyki w latach 2011-2012, które objęło ogółem 346 osób powyżej 18. roku życia, z których 267 było płci żeńskiej, a 79 – męskiej. Obserwowano wartości stężenia cukru i cholesterolu we krwi obwodowej, ciśnienia krwi, wzrost i wagę. Mierzono także wartość współczynnika BMI oraz całkowitą ilość tkanki tłuszczowej w organizmie przy użyciu urządzenia do pomiaru tkanki tłuszczowej firmy Omron. Aparat ten pozwala na określenie całkowitej ilości tkanki tłuszczowej w organizmie w oparciu o metodę pomiaru impedancji bioelektrycznej.

5

Modelowanie przepływów a choroby sercowo-naczyniowe

Tomasiak E., Gacek A., Barbachowski E., Klarecki K.

Hydraulika i Pneumatyka

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2012

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nr 6

25-28

PL

Wskazano na możliwość wykorzystania doświadczeń z badań układów hydraulicznych w pracach nad chorobami układu sercowo-naczyniowego. Wskazano na brak podstaw do określenia przyczyn powstawania ego typu chorób, na co wskazały też wyniki modelowania przepływów przez przeszkodę. Odniesiono się do analizy zjawisk przepływu krwi, jako specyficznego przypadku układu hydraulicznego.

EN

The experience o hydraulic systems research in the development of diseases of the cardiovascular system can be useful. Problems that are quoted on the mechanics of movement indicate the complexity of the circulatory system does not give a convincing answer o he causes of cardiovascular disease. Phenomena of blood flow, as a specific case o he hydraulic system has been discussed.

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Images of corona discharges in patients with cardiovascular diseases as a preliminary analysis for research of the influence of textiles on images of corona discharges in textiles

Ciesielska-Wróbel I L, Szadkowska I., Masajtis J., Goch J. H.

Autex Research Journal

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2010

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Vol. 10, no. 1

26--30

EN

The aim of the study was to assess changes in images of corona discharges (ICD) in patients with cardiovascular diseases A corona discharge is an electrical discharge brought on by gases surrounding a conductor - animate or inanimate objects. Methods: The study population of 126 persons (81 men and 45 women) was divided into two groups: the study group consisted of 96 patients with coronary heart disease and the control group composed of 30 healthy persons. The study methods included recording of corona discharges of fingertips of both hands by using the Gas Discharge Visualization (GDV) Camera and analyzing changes in images of corona discharges dependent on conditions of medical examinations of patients, their frame of mind, age, gender, heart rate, blood pressure, serum potassium concentration, and the course of coronary heart disease. Results: Age, gender, temperature in examination rooms as well as frame of mind of the study population exerted a similar effect on ICD in both groups. Heart rate, blood pressure and the pattern of coronary heart disease exerted varied effects on the patients' ICD parameters in the study group. Conclusions: The analysis of changes in ICD may be a source of information about the effect of physiological and pathophysiological changes in the human health state, physical as well as mental.

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Piąta Multidisciplinarna Konferencja Nauki o Leku

Przemysł Chemiczny

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2006

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T. 85, nr 6

435-437