Wyniki wyszukiwania - Biblioteka Nauki

1

Impedance cardiography – optimization and efficacy evaluation of antihypertensive treatment

100%

Panasiuk-Kamińska K. , Szeliga-Król J. , Jaroszyński A.

Family Medicine & Primary Care Review

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2016

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nr 3

321-324

2

Implementation of Impedance Method in Syncope Treatment

100%

Pęczalski K. , Wojciechowski D. , Dunajski Z. , Pałko T.

Polish Journal of Medical Physics And Engineering

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2007

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tom 13

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nr 2

93-103

EN

Current syncope treatment by cardiac pacing is limited to patients developing cardiodepressive reaction. There is strong need to apply this method to other types of reaction. Presented method shows, that impedance method can be applied for early detection of vasodepressive syncope. Thus the method can be applied for antivasovagal pacing in syncopic patients.

3

Impedance cardiography – Old method, new opportunities. Part I. Clinical applications

88%

Siedlecka J. , Siedlecki P. , Bortkiewicz A.

International Journal of Occupational Medicine and Environmental Health

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2015

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tom 28

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nr 1

27-33

EN

Monitoring of cardiovascular hemodynamic changes requires a very expensive and highly specialized equipment and skilled medical personnel. Up to the present time, an inexpensive, non-invasive and easy-to-use method which, like Doppler echocardiography, magnetic resonance angiography or radionuclide imaging, would assess hemodynamics of the cardiovascular system was not available. A method known as impedance cardiography (ICG) or thoracic electrical bioimpedance cardiography (TEBC) meets those criteria. It is non-invasive, which is of a particular advantage over the conventional methods that require catheterization. As a result, the patient is not at risk of possible complications and the procedure is less expensive and easier. Impedance cardiography, despite its non-invasive character, has not been so far extensively used for monitoring of hemodynamic parameters in hospitalized patients. Various authors report that attempts have been continued to compare the results from ICG and those obtained by other diagnostic methods. This paper presents the use of impedance cardiography in diagnosis of hypertension, cardiac insufficiency, differentiating the causes of acute dyspnea, as well as in assessing the effects of cardiac rehabilitation in patients with heart failure.

4

Cardiovascular response to exercise in hypertension – clinical characteristics of ASSECURE study participants

88%

Kurpaska M. , Krzesiński P. , Gielerak G. , Uziębło-Życzkowska B. , Banak M. , Maciorowska M. , Skrobowski A. , Stańczyk A. , Piotrowicz K.

Pediatria i Medycyna Rodzinna

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2019

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tom 15

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nr 1

47-56

EN

Aim: Arterial hypertension leads to progressive cardiovascular dysfunction and heart failure. The aim of the study was to assess exercise capacity in hypertensives with the use of a cardiopulmonary exercise test, impedance cardiography and 6-minute walk test with special emphasis on haemodynamic response to exercise workload. Methods: 114 patients (53.5% women, 55.7 ± 9.1 years) were evaluated for reported symptoms, N-terminal pro-B-type natriuretic peptide (NTproBNP) levels, echocardiographic parameters and exercise capacity with 6-minute walk test, cardiopulmonary exercise test and haemodynamic parameters (by means of impedance cardiography). Results: 50% of patients had reported symptoms of impaired exercise tolerance, mostly dyspnoea on exertion (37.7%). NTproBNP levels exceeded 125 pg/mL in 19.3% of patients. Left ventricular diastolic dysfunction was found in 8.8% and heart failure was diagnosed in 6.2% of patients. A wide range of peak oxygen uptake (peak VO2) and 6-minute walk test distance was observed: 19.4 ± 5.2 mL/min/kg and 526.7 ± 112.0 m, respectively. A major proportion of patients demonstrated decreased exercise capacity parameters: 56.1% achieving peak VO2 < 22 mL/min/m2; 45.9% achieving peak VO2 < 80% of the predictive value; 37.3% achieving 6-minute walk test distance shorter than the predicted values. The impedance cardiography recorded at peak exercise: heart rate 147.2 ± 22.4 bpm, stroke volume 110.2 ± 21.8 mL, cardiac output 15.9 ± 4.2 L/min, peak systemic vascular resistance 587.4 ± 168.0 dyn.s/cm5. Conclusions: Although a very small proportion of patients with uncomplicated arterial hypertension meet the criteria for being diagnosed with heart failure, the symptoms of impaired exercise tolerance as well as abnormal results of objective exercise capacity assessments are quite common in these patients.

PL

Cel: Nadciśnienie tętnicze prowadzi do postępującej dysfunkcji układu krążenia i niewydolności serca. Celem pracy była ocena wydolności fizycznej chorych z nadciśnieniem tętniczym z wykorzystaniem sercowo-płucnego testu wysiłkowego, wysiłkowej kardiografii impedancyjnej oraz 6-minutowego testu marszowego, ze szczególnym uwzględnieniem odpowiedzi hemodynamicznej na obciążenie wysiłkiem. Metody: 114 chorych (53,5% kobiet, wiek 55,7 ± 9,1 roku) oceniono pod względem zgłaszanych objawów, stężenia N-końcowego propeptydu natriuretycznego typu B (N-terminal pro-B-type natriuretic peptide, NTproBNP), wykładników echokardiograficznych oraz wydolności fizycznej za pomocą 6-minutowego testu marszowego i sercowo-płucnego testu wysiłkowego, a także parametrów hemodynamicznych za pomocą wysiłkowej kardiografii impedancyjnej. Wyniki: W badanej grupie 50% osób zgłaszało obniżenie tolerancji wysiłku, w tym 37,7% duszność wysiłkową. U 19,3% chorych stężenie NTproBNP przekroczyło wartość 125 pg/ml. Dysfunkcję rozkurczową stwierdzono u 8,8% z nich, ale kryteria rozpoznania niewydolności serca z zachowaną frakcją wyrzutową spełniło jedynie 6,2%. Obserwowano szeroki zakres szczytowego pochłaniania tlenu (peak VO2) i dystansu 6-minutowego testu marszowego, odpowiednio 19,4 ± 5,2 ml/min/kg i 526,7 ± 112,0 m. Wysoki odsetek badanych prezentował obniżone parametry wydolności fizycznej: 56,1% osiągnęło peak VO2 < 22 ml/min/m2, a 45,9% – peak VO2 < 80% wartości predykcyjnej; 37,3% badanych nie osiągnęło należnej wartości dystansu 6-minutowego testu marszowego. W wysiłkowej kardiografii impedancyjnej zarejestrowano na szczycie wysiłku: częstość rytmu serca 147,2 ± 22,4/min, objętość wyrzutową 110,2 ± 21,8 ml, pojemność minutową 15,9 ± 4,2 l/min, opór obwodowy 587,4 ± 168,0 dyn.s/cm5. Wnioski: Objawy obniżonej tolerancji wysiłku i nieprawidłowe wyniki obiektywnej oceny wydolności fizycznej u pacjentów z niepowikłanym nadciśnieniem tętniczym są częste, chociaż niewielki odsetek tych chorych spełnia kryteria diagnostyczne niewydolności serca.

5

Impedance cardiography – Old method, new opportunities. Part II. Testing of cardiovascular response to various factors of work environment

75%

Siedlecka J. , Siedlecki P. , Bortkiewicz A.

International Journal of Occupational Medicine and Environmental Health

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2015

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tom 28

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nr 1

34-41

EN

Impedance cardiography seems to be a very good, although underappreciated diagnostic method. What may distinguish it from among the many research methods is the fact that it enables non-invasive monitoring of cardiac output, stroke volume and systemic vascular resistance. Holter recording of the hemodynamic parameters makes it possible to study them not only in stationary (hospital, outpatient clinic) conditions, but also during household or professional activities, e.g., during road vehicle driving. Assessment of the trends of changes in the circulatory system of the employee at work makes it possible to judge whether the type of work performed by the worker is well tolerated – whether it is not too hard or too stressful. This is important, therefore, impedance cardiography can be extensively used in occupational medicine. Provision of preventive care to workers according to current standards requires, on the one hand, the use of the latest diagnostic methods while, on the other hand, the methods must be inexpensive, because otherwise the employer would not be able or willing to pay the associated costs. Impedance cardiography meets those criteria; however, few data is available in literature worldwide on the use of this method in the research on the impact of occupational work on cardiovascular responses of the employees. This work reports the use of impedance cardiography in studies on the various aspects of work environment.

6

Cardiovascular testing of seasickness in healthy volunteers on life rafts

75%

Molisz A. , Ryk M. , Rataj M. , Kołaczyńska B. , Nowicka-Sauer K. , Przewoźny T. , Sauer M. , Gutknecht P. , Trzeciak B. , Siebert J.

International Journal of Occupational Medicine and Environmental Health

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2020

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tom 33

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nr 4

467-477

EN

ObjectivesThe role of the cardiovascular system in the development of seasickness remains uncertain.Material and MethodsOverall, 18 healthy students (10 males and 8 females) aged 18–24 years volunteered in the project, spending 2–7 h on life rafts. The cardiovascular system was examined with impedance cardiography. Susceptibility and symptoms of seasickness were evaluated by the Motion Sickness Susceptibility Questionnaire Shortform (MSSQ-Short) and the Motion Sickness Assessment Questionnaire (MSAQ). The Visual Analogue Scale (VAS), ranging 0–10, was used to assess nausea, dizziness and mood. The parameters were assessed at 2 time points.ResultsDifferences in the heart rate (HR), the thoracic fluid content index (TFCI), the stroke index (SI) and the Heather index (HI) before launching the life rafts and after leaving them were observed (78.6, 20.8, 55.6 and 15.9 vs. 70.1, 19.7, 60.5 and 17.9, with p-values of 0.002, <0.001, 0.003 and 0.004, respectively). Females reacted with changes in SI and HR more vividly, whereas males regulated more HI and TFCI. In addition, HR correlated significantly with the central and peripheral symptoms in MSAQ, stroke volume (SV) with peripheral and sopite-related ones, SI with overall ones, and pulse pressure with overall, gastrointestinal and central ones (Spearman’s rank correlation coefficient [ρ] was –0.478, –0.711, 0.476, 0.472, 0.525, –0.476, –0.579 and –0.584, respectively). As regards MSSQ-Short, it correlated negatively with sopite-related symptoms in MSAQ (ρ= –0.486). Mood in VAS correlated significantly with gastrointestinal symptoms, SI and the cardiac index (CI) (ρ = –0.752, –0.492 and –0.489, respectively).ConclusionsIt was found that HR correlated negatively, and SV/SI correlated positively, with the severity of seasickness symptoms measured with MSAQ. Gender is probably an independent factor influencing reactions to motion. Women react with SI increase whereas men react with increased heart contractility (HI rise). Negative mood in seasickness evaluated with VAS seems to be mostly determined by gastrointestinal symptoms assessed with MSAQ and diminished cardiovascular indices (both CI and SI).

7

Dwukanałowa kardiografia impedancyjna stosowana do oceny dyssynchronii międzykomorowej serca : wstępne wyniki

75%

Pęczalski K. , Pałko T. , Wojciechowski D. , Dunajski Z. , Kowalewski M. , Woźniewska I. , Jędrasik P.

Elektronika : konstrukcje, technologie, zastosowania

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2011

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tom Vol. 52, nr 11

130-132

PL

Stała resynchronizacyjna stymulacja serca jest metodą leczenia pacjentów z lewokomorową dysfunkcją skurczową serca. Stymulacja synchronizuje pracę serca poprzez niezależne pobudzanie lewej i prawej komory korygując dyssynchronię międzykomorową. Około 30 ... 40% chorych nie odpowiada na tą elektroterapię. W celu poprawienia skuteczności metody autorzy zaproponowali ocenę dyssynchronii międzykomorowej serca, metodą dwukanałowej kardiografii impedancyjnej. Proponowana metoda będzie służyć do kwalifikacji pacjentów do wszczepienia oraz późniejszego optymalizowania parametrów resynchronizującego rozrusznika serca. Wstępne badania wykazały, że dwukanałowa kardiografia impedancyjna wydaje się być użytecznym narzędziem do oceny dyssynchronii międzykomorowej u pacjentów leczonych stałą resynchronizującą stymulacją serca.

EN

The cardiac resynchronization therapy is an effective treatment for systolic heart failure patients. Independent electrical stimulation of left and right ventricle corrects of ventricular dyssynchrony. About 30 ... 40% of treated patients don't respond to therapy. In order to improve clinical outcome authors propose the two channel impedance cardiography for assessment of ventricular dyssynchrony. The proposed method will be applied for validation of patient for resynchronization pacing and optimization of implanted pacemakers. The preliminary study has showed that two channel impedance cardiography seems to be the promising tool for assessment of ventricular dyssynchrony in patient treated by cardiac resynchronization therapy.

8

Zmiany parametrów kurczliwości mięśnia sercowego u osób zdrowych po jednym zabiegu kriostymulacji ogólnoustrojowej

63%

Zalewski P. , Klawe J. , Pawlak J. , Tafil-Klawe M. , Bitner A. , Lewandowski A.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2011

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tom Vol. 17, nr 4

257-261

PL

Celem pracy była analiza wpływu krioterapii ogólnoustrojowej na układ sercowo-naczyniowy, w szczególności na parametry kurczliwości mięśnia sercowego. Badania przeprowadzono na grupie 32 zdrowych mężczyzn, poddanych jednokrotnemu zabiegowi krioterapii ogólnoustrojowej. Ocenę czynnościową układu sercowo-naczyniowego przeprowadzono za pomocą systemu Task ForceŽ Monitor (TFM). Rejestrację badanych sygnałów biologicznych rozpoczęto przed zabiegiem krioterapii ogólnoustrojowej i kontynuowano w czasie sześciu godzin po jego zakończeniu. Analiza statystyczna uzyskanych wyników wykazała istotny wpływ zabiegu kriostymulacji ogólnoustrojowej na parametry kurczliwości mięśnia sercowego.

EN

The aim of the study was the assessment of the influence of the whole-body cryostimulation (WBC) on the cardiovascular system, in particular, on the parameters of the heart contractility. The study included 32 healthy men subjected to a single whole-body cryotherapy procedure. The functional evaluation of the cardiovascular system was carried out on the basis of Task ForceŽ Monitor (TFM). The registration of biological signals was done before the procedure and continued within six hours after WBC. The statistical analysis of the results revealed that the whole-body cryostimulation causes significant changes in the parameters of the heart.

9

Detection of valvular heart diseases using impedance cardiography ICG

63%

Chabchoub S. , Mansouri S. , Ben Salah R.

Biocybernetics and Biomedical Engineering

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2018

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tom Vol. 38, no. 2

251--261

EN

Impedance cardiography (ICG) is a simple, non-invasive and cost effective tool for monitor-ing hemodynamic parameters. It has been successfully used to diagnose several cardiovas-cular diseases, like the heart failure and myocardial infarction. In particular, valvular heart disease (VHD) is characterized by the affection of one or more heart valves: mitral, aortic, tricuspid or pulmonary valves and it is usually diagnosed using the Doppler echocardiogra- phy. However, this technique is rather expensive, requires qualified expertise, discontinu- ous, and often not necessary to make just a simple diagnosis. In this paper, a new computer aided diagnosis system is proposed to detect VHD using the ICG signals. Six types of ICG heartbeats are analyzed and classified: normal heartbeats (N), mitral insufficiency heart-beats (MI), aortic insufficiency heartbeats (AI), mitral stenosis heartbeats (MS), aortic steno-sis heartbeats (AS), and pulmonary stenosis heartbeats (PS). The proposed methodology is validated on 120 ICG recordings. Firstly, ICG signal is denoised using the Daubechies wavelet family with order eight (db8). Then, these signals are segmented into several heartbeats and, later, subjected to the linear prediction LP and discrete wavelet transform DWT approaches to extract temporal and time–frequency features, respectively. In order to reduce the number of features and select the most relevant ones among them, the Student's t-test is applied. Therefore, a total of 16 features are selected (3 temporal features and 13 time– frequency features). For the classification step, the support vector machine SVM and k-nearest neighbors KNN classifiers are used. Different combinations between extracted features and classifiers are proposed. Hence, experimental results showed that the combi-nation between temporal features, time–frequency features and SVM classifier achieved the highest classification performance in classifying the N, MI, MS, AI, AS and PS heartbeats with 98.94% of overall accuracy.

10

Determination of stroke volume of the ventricular assist device using bioimpedance method

51%

Sobotnicki A. , Gacek A. , Pałko T. , Mocha J. , Badura G. , Czerw M.

Journal of Medical Informatics & Technologies

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2013

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tom Vol. 22

235--241

EN

The stroke volume of pulsatile ventricular assist device (VAD) is one of the key clinical indicators to evaluate the adequacy of the process of mechanical heart assistance and ensuring the patient’s safety. In order to evaluate the volume changes in VAD blood chamber, a bioimpedance method was applied, based on volumetric electric conductivity of the blood. Periodic changes in VAD volume during its operation result in a pulsatile impedance waveform; its amplitude in the subperiods of filling and ejection correlates with blood volume in the chamber. The paper presents the method of analysis of the bioimpedance signal recorded in VAD blood chamber with a reference to the classical method of analysing the cardioimpedance signal from the patient’s thorax. The paper also presents the results of determining stroke volume of blood chamber based on an empirical formula that has been developed.