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1.
Int J Cardiol ; 398: 131596, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37979788

RESUMEN

BACKGROUND: Peripartum cardiomyopathy (PPCM) is a global disease with substantial morbidity and mortality. The aim of this study was to analyze to what extent socioeconomic factors were associated with maternal and neonatal outcomes. METHODS: In 2011, >100 national and affiliated member cardiac societies of the European Society of Cardiology (ESC) were contacted to contribute to a global PPCM registry, under the auspices of the ESC EORP Programme. We investigated the characteristics and outcomes of women with PPCM and their babies according to individual and country-level sociodemographic factors (Gini index coefficient [GINI index], health expenditure [HE] and human developmental index [HDI]). RESULTS: 739 women from 49 countries (Europe [33%], Africa [29%], Asia-Pacific [15%], Middle East [22%]) were enrolled. Low HDI was associated with greater left ventricular (LV) dilatation at time of diagnosis. However, baseline LV ejection fraction did not differ according to sociodemographic factors. Countries with low HE prescribed guideline-directed heart failure therapy less frequently. Six-month mortality was higher in countries with low HE; and LV non-recovery in those with low HDI, low HE and lower levels of education. Maternal outcome (death, re-hospitalization, or persistent LV dysfunction) was independently associated with income. Neonatal death was significantly more common in countries with low HE and low HDI, but was not influenced by maternal income or education attainment. CONCLUSIONS: Maternal and neonatal outcomes depend on country-specific socioeconomic characteristics. Attempts should therefore be made to allocate adequate resources to health and education, to improve maternal and fetal outcomes in PPCM.


Asunto(s)
Cardiología , Cardiomiopatías , Complicaciones Cardiovasculares del Embarazo , Recién Nacido , Femenino , Humanos , Embarazo , Periodo Periparto , Cardiomiopatías/diagnóstico , Cardiomiopatías/epidemiología , Cardiomiopatías/complicaciones , Factores Económicos , Sistema de Registros , Complicaciones Cardiovasculares del Embarazo/diagnóstico , Complicaciones Cardiovasculares del Embarazo/epidemiología , Complicaciones Cardiovasculares del Embarazo/terapia
2.
Eur J Heart Fail ; 26(1): 34-42, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37823238

RESUMEN

AIMS: There are few prospective reports of 1-year outcomes for women with peripartum cardiomyopathy (PPCM). We report findings from the European Society of Cardiology EURObservational Research Programme PPCM Registry. METHODS AND RESULTS: The registry enrolled women from 51 countries from 2012 to 2018. Eligibility included: (i) a peripartum state, (ii) signs or symptoms of heart failure, (iii) left ventricular (LV) ejection fraction ≤45%, (iv) exclusion of alternative causes of heart failure. We report mortality, thromboembolism, stroke, rehospitalization, LV recovery and remodelling at 1 year. Differences between regions were compared. One-year mortality data were available in 535 (71%) women and follow-up differed across regions. At 1 year, death from any cause occurred in 8.4% of women, with regional variation (Europe 4.9%, Africa 6.5%, Asia-Pacific 9.2%, Middle East 18.9%; p < 0.001). The frequencies of thromboembolism and stroke were 6.3% and 2.5%, respectively, and were similar across regions. A total of 14.0% of women had at least one rehospitalization and 3.5% had recurrent rehospitalizations (i.e. two or more). Overall, 66.1% of women had recovery of LV function (22% between 6 months and 1 year), with a mean LV ejection fraction increase from baseline of 21.2% (±13.6). Recovery occurred most frequently in Asia-Pacific (77.5%) and least frequently in the Middle East (32.7%). There were significant regional differences in the use of heart failure pharmacotherapies. CONCLUSIONS: Approximately 1 in 12 women with PPCM had died by 1 year and thromboembolism and stroke occurred in 6.3% and 2.5%, respectively. Around 1 in 7 women had been rehospitalized and, in 1 in 3, LV recovery had not occurred. PPCM is associated with substantial mortality and morbidity globally.


Asunto(s)
Cardiomiopatías , Insuficiencia Cardíaca , Complicaciones Cardiovasculares del Embarazo , Accidente Cerebrovascular , Tromboembolia , Femenino , Humanos , Masculino , Embarazo , Insuficiencia Cardíaca/epidemiología , Insuficiencia Cardíaca/terapia , Insuficiencia Cardíaca/complicaciones , Periodo Periparto , Estudios Prospectivos , Cardiomiopatías/diagnóstico , Función Ventricular Izquierda , Volumen Sistólico , Sistema de Registros , Tromboembolia/epidemiología , Tromboembolia/etiología , Complicaciones Cardiovasculares del Embarazo/diagnóstico
3.
Int J Gen Med ; 16: 3933-3945, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37670928

RESUMEN

Background: Multiple comorbidities and physiological changes play a role in a range of heart failure conditions and influence the most effective approach to exercise-based rehabilitation. This research aimed to examine and compare the outcomes of continuous training at three different intensities, focusing on left ventricular (LV) remodeling, functional capacity, and quality of life among patients with heart failure with reduced ejection fraction (HFrEF). Methods: In this randomized control trial, a total of 60 male patients (average age: 54.33 ±2.35 years) with HFrEF were randomly allocated into three groups: 1) High-intensity continuous training group (HICT), 2) Moderate-intensity continuous training group (MICT), and 3) Low-intensity continuous training group (LICT). All the training was performed on a bicycle ergometer 3 times/week for 12 weeks. Echocardiographic parameters (left ventricular ejection fraction, left ventricular end-diastolic dimension, left ventricular end-systolic dimension, N-terminal pro-B-type natriuretic peptide (NT-proBNP), quality of life (Minnesota Living with Heart Failure Questionnaire), and functional capacity (6-minute walking test) were assessed before and the end of the study. Results: The HICT group demonstrated the greatest improvements in all measured variables when compared to the other two groups (P < 0.05). These findings were consistent across all measured outcomes. Conclusion: It was determined that HICT appears to yield the most favorable outcomes in enhancing echocardiographic measures, NT-proBNP levels, quality of life, and functional capacity among HFrEF patients.

4.
Nat Nanotechnol ; 17(8): 864-870, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35725927

RESUMEN

Continuous monitoring of arterial blood pressure (BP) in non-clinical (ambulatory) settings is essential for understanding numerous health conditions, including cardiovascular diseases. Besides their importance in medical diagnosis, ambulatory BP monitoring platforms can advance disease correlation with individual behaviour, daily habits and lifestyle, potentially enabling analysis of root causes, prognosis and disease prevention. Although conventional ambulatory BP devices exist, they are uncomfortable, bulky and intrusive. Here we introduce a wearable continuous BP monitoring platform that is based on electrical bioimpedance and leverages atomically thin, self-adhesive, lightweight and unobtrusive graphene electronic tattoos as human bioelectronic interfaces. The graphene electronic tattoos are used to monitor arterial BP for >300 min, a period tenfold longer than reported in previous studies. The BP is recorded continuously and non-invasively, with an accuracy of 0.2 ± 4.5 mm Hg for diastolic pressures and 0.2 ± 5.8 mm Hg for systolic pressures, a performance equivalent to Grade A classification.


Asunto(s)
Grafito , Tatuaje , Presión Arterial , Determinación de la Presión Sanguínea , Monitoreo Ambulatorio de la Presión Arterial , Humanos
5.
Sci Rep ; 12(1): 319, 2022 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-35013376

RESUMEN

Continuous monitoring of blood pressure (BP) is essential for the prediction and the prevention of cardiovascular diseases. Cuffless BP methods based on non-invasive sensors integrated into wearable devices can translate blood pulsatile activity into continuous BP data. However, local blood pulsatile sensors from wearable devices suffer from inaccurate pulsatile activity measurement based on superficial capillaries, large form-factor devices and BP variation with sensor location which degrade the accuracy of BP estimation and the device wearability. This study presents a cuffless BP monitoring method based on a novel bio-impedance (Bio-Z) sensor array built in a flexible wristband with small-form factor that provides a robust blood pulsatile sensing and BP estimation without calibration methods for the sensing location. We use a convolutional neural network (CNN) autoencoder that reconstructs an accurate estimate of the arterial pulse signal independent of sensing location from a group of six Bio-Z sensors within the sensor array. We rely on an Adaptive Boosting regression model which maps the features of the estimated arterial pulse signal to systolic and diastolic BP readings. BP was accurately estimated with average error and correlation coefficient of 0.5 ± 5.0 mmHg and 0.80 for diastolic BP, and 0.2 ± 6.5 mmHg and 0.79 for systolic BP, respectively.


Asunto(s)
Presión Arterial , Técnicas Biosensibles/instrumentación , Determinación de la Presión Sanguínea/instrumentación , Transductores , Dispositivos Electrónicos Vestibles , Muñeca/irrigación sanguínea , Adulto , Impedancia Eléctrica , Diseño de Equipo , Humanos , Redes Neurales de la Computación , Valor Predictivo de las Pruebas , Flujo Pulsátil , Reproducibilidad de los Resultados , Procesamiento de Señales Asistido por Computador , Factores de Tiempo , Adulto Joven
6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 2864-2870, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34891845

RESUMEN

There is an urgent need to bring forth portable, low-cost, point-of-care diagnostic instruments to monitor patient health and wellbeing. This is elevated by the COVID-19 global pandemic in which the availability of proper lung imaging equipment has proven to be pivotal in the timely treatment of patients. Electrical impedance tomography (EIT) has long been studied and utilized as such a critical imaging device in hospitals especially for lung ventilation. Despite decades of research and development, many challenges remain with EIT in terms of 1) optimal image reconstruction algorithms, 2) simulation and measurement protocols, 3) hardware imperfections, and 4) uncompensated tissue bioelectrical physiology. Due to the inter-connectivity of these challenges, singular solutions to improve EIT performance continue to fall short of the desired sensitivity and accuracy. Motivated to gain a better understanding and optimization of the EIT system, we report the development of a bioelectric facsimile simulator demonstrating the dynamic operations, sensitivity analysis, and reconstruction outcome prediction of the EIT sensor with stepwise visualization. By building a sandbox platform to incorporate full anatomical and bioelectrical properties of the tissue under study into the simulation, we created a tissue-mimicking phantom with adjustable EIT parameters to interpret bioelectrical interactions and to optimize image reconstruction accuracy through improved hardware setup and sensing protocol selections.


Asunto(s)
COVID-19 , Impedancia Eléctrica , Humanos , SARS-CoV-2 , Tomografía
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 7480-7484, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34892823

RESUMEN

Continuous and unobtrusive blood pressure (BP) monitoring provides significant advantages in predicting the onset of cardiovascular disease. Bio-impedance sensing is a prominent method for continuous BP monitoring in a wearable form factor that can effectively measure blood pulsations from the arteries and translate them into BP. However, assessing the quality of the bio-impedance signal captured from small electrodes placed on the skin is required to determine the accuracy of BP estimation. In wearable devices, frequent movements of the electrodes on the skin are expected which cause non-optimal contact quality between the electrodes and the skin. This can lead to high skin-electrode impedance which can cause saturation of the current injection module of the bio-impedance device. This phenomenon degrades the signal quality In this paper, we present an automatic gain control (AGC) circuit that controls the amplitude of the current injection into the body based on sensing the skin-electrode impedance to ensure injection of maximum current to maximize the signal-to-noise ratio (SNR) while avoiding saturation of the current injection module. In this work, the proposed AGC method shows higher quality of blood pulsation from bio-impedance signal measured from a human subject with 1.59 dB improvement in SNR which leads to a better estimation of blood pressure.Clinical Relevance- The proposed automatic gain control (AGC) circuit establishes a more accurate method of continuous blood pressure monitoring using bio-impedance.


Asunto(s)
Determinación de la Presión Sanguínea , Presión Sanguínea , Impedancia Eléctrica , Electrodos , Humanos , Relación Señal-Ruido
8.
Eur J Heart Fail ; 23(12): 2058-2069, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34114268

RESUMEN

AIMS: Hypertensive disorders occur in women with peripartum cardiomyopathy (PPCM). How often hypertensive disorders co-exist, and to what extent they impact outcomes, is less clear. We describe differences in phenotype and outcomes in women with PPCM with and without hypertensive disorders during pregnancy. METHODS AND RESULTS: The European Society of Cardiology EURObservational Research Programme PPCM Registry enrolled women with PPCM from 2012-2018. Three groups were examined: (i) women without hypertension (PPCM-noHTN); (ii) women with hypertension but without pre-eclampsia (PPCM-HTN); (iii) women with pre-eclampsia (PPCM-PE). Maternal (6-month) and neonatal outcomes were compared. Of 735 women included, 452 (61.5%) had PPCM-noHTN, 99 (13.5%) had PPCM-HTN and 184 (25.0%) had PPCM-PE. Compared to women with PPCM-noHTN, women with PPCM-PE had more severe symptoms (New York Heart Association class IV in 44.4% vs. 29.9%, P < 0.001), more frequent signs of heart failure (pulmonary rales in 70.7% vs. 55.4%, P = 0.002), a higher baseline left ventricular ejection fraction (LVEF) (32.7% vs. 30.7%, P = 0.005) and a smaller left ventricular end-diastolic diameter (57.4 ± 6.7 mm vs. 59.8 ± 8.1 mm, P = 0.001). There were no differences in the frequencies of death from any cause, rehospitalization for any cause, stroke, or thromboembolic events. Compared to women with PPCM-noHTN, women with PPCM-PE had a greater likelihood of left ventricular recovery (LVEF ≥ 50%) (adjusted odds ratio 2.08, 95% confidence interval 1.21-3.57) and an adverse neonatal outcome (composite of termination, miscarriage, low birth weight or neonatal death) (adjusted odds ratio 2.84, 95% confidence interval 1.66-4.87). CONCLUSION: Differences exist in phenotype, recovery of cardiac function and neonatal outcomes according to hypertensive status in women with PPCM.


Asunto(s)
Cardiomiopatías , Insuficiencia Cardíaca , Hipertensión Inducida en el Embarazo , Complicaciones Cardiovasculares del Embarazo , Cardiomiopatías/complicaciones , Cardiomiopatías/diagnóstico , Cardiomiopatías/epidemiología , Femenino , Insuficiencia Cardíaca/complicaciones , Humanos , Hipertensión Inducida en el Embarazo/epidemiología , Periodo Periparto , Embarazo , Sistema de Registros , Volumen Sistólico , Función Ventricular Izquierda
9.
Eur J Heart Fail ; 23(4): 527-540, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33609068

RESUMEN

This position paper focusses on the pathophysiology, diagnosis and management of women diagnosed with a cardiomyopathy, or at risk of heart failure (HF), who are planning to conceive or present with (de novo or previously unknown) HF during or after pregnancy. This includes the heterogeneous group of heart muscle diseases such as hypertrophic, dilated, arrhythmogenic right ventricular and non-classified cardiomyopathies, left ventricular non-compaction, peripartum cardiomyopathy, Takotsubo syndrome, adult congenital heart disease with HF, and patients with right HF. Also, patients with a history of chemo-/radiotherapy for cancer or haematological malignancies need specific pre-, during and post-pregnancy assessment and counselling. We summarize the current knowledge about pathophysiological mechanisms, including gene mutations, clinical presentation, diagnosis, and medical and device management, as well as risk stratification. Women with a known diagnosis of a cardiomyopathy will often require continuation of drug therapy, which has the potential to exert negative effects on the foetus. This position paper assists in balancing benefits and detrimental effects.


Asunto(s)
Cardiología , Cardiomiopatías , Cardiopatías Congénitas , Insuficiencia Cardíaca , Complicaciones Cardiovasculares del Embarazo , Adulto , Femenino , Humanos , Periodo Periparto , Embarazo , Medición de Riesgo
10.
IEEE Trans Biomed Circuits Syst ; 15(1): 143-158, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33577456

RESUMEN

Cardiovascular disease (CVD) threatens the lives of many and affects their productivity. Wearable sensors can enable continuous monitoring of hemodynamic parameters to improve the diagnosis and management of CVD. Bio-Impedance (Bio-Z) is an effective non-invasive sensor for arterial pulse wave monitoring based on blood volume changes in the artery due to the deep penetration of its current signal inside the tissue. However, the measured data are significantly affected by the placement of electrodes relative to the artery and the electrode configuration. In this work, we created a Bio-Z simulation platform that models the tissue, arterial pulse wave, and Bio-Z sensing configuration using a 3D circuit model based on a time-varying impedance grid. A new method is proposed to accurately simulate the different tissue types such as blood, fat, muscles, and bones in a 3D circuit model in addition to the pulsatile activity of the arteries through a variable impedance model. This circuit model is simulated in SPICE and can be used to guide design decisions (i.e. electrode placement relative to the artery and electrode configuration) to optimize the monitoring of pulse wave prior to experimentation. We present extensive simulations of the arterial pulse waveform for different sensor locations, electrode sizes, current injection frequencies, and artery depths. These simulations are validated by experimental Bio-Z measurements.


Asunto(s)
Análisis de la Onda del Pulso , Pulso Arterial , Impedancia Eléctrica , Electrodos , Frecuencia Cardíaca
11.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3945-3948, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33018863

RESUMEN

Continuous monitoring of cardiac parameters such as blood pressure (BP) and pulse transit time (PTT) from wearable devices can improve the diagnosis and management of the cardiovascular disease. Continuous monitoring of these parameters depends on monitoring arterial pulse wave based on the blood volume changes in the artery using non-invasive sensors such as bio-impedance (Bio-Z). PTT and BP monitoring require the measurement of multiple pulse signals along the artery through the placement of multiple sensors within a small distance. Conventionally, these Bio-Z sensors are excited by a single shared current source, which results in low directivity and distortion of pulse signal due to the interaction of the different sensors together. For a localized pulse sensing, each sensor should focus on a certain point on the artery to provide the most accurate arterial pulse wave, which improves PTT and BP readings. In this paper, we propose a multi-source multi-frequency method for multi-sensor Bio-Z measurement that relies on using separate current sources for each sensor with different frequencies to allow the separation of these signals in the frequency domain, which results in isolation in the spatial domain. The effectiveness of the new method was demonstrated by a reduction in the inter-beat-interval (IBI) root mean square error (RMSE) by 19% and an increase of average PTT by 15% compared to the conventional method.


Asunto(s)
Determinación de la Presión Sanguínea , Pulso Arterial , Presión Sanguínea , Impedancia Eléctrica , Análisis de la Onda del Pulso
12.
IEEE Trans Biomed Circuits Syst ; 14(4): 757-774, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32746337

RESUMEN

Continuous and robust monitoring of physiological signals is essential in improving the diagnosis and management of cardiovascular and respiratory diseases. The state-of-the-art systems for monitoring vital signs such as heart rate, heart rate variability, respiration rate, and other hemodynamic and respiratory parameters use often bulky and obtrusive systems or depend on wearables with limited sensing methods based on repetitive properties of the signals rather than the morphology. Moreover, multiple devices and modalities are typically needed for capturing various vital signs simultaneously. In this paper, we introduce ImpediBands: small-sized distributed smart bio-impedance (Bio-Z) patches, where the communication between the patches is established through the human body, eliminating the need for electrical wires that would create a common potential point between sensors. We use ImpediBands to collect instantaneous measurements from multiple locations over the chest at the same time. We propose a blind source separation (BSS) technique based on the second-order blind identification (SOBI) followed by signal reconstruction to extract heart and lung activities from the Bio-Z signals. Using the separated source signals, we demonstrate the performance of our system via providing strong confidence in the estimation of heart and respiration rates with low RMSE (HRRMSE = 0.579 beats per minute, RRRMSE = 0.285 breaths per minute), and high correlation coefficients (rHR = 0.948, rRR = 0.921).


Asunto(s)
Impedancia Eléctrica , Monitoreo Fisiológico/instrumentación , Procesamiento de Señales Asistido por Computador/instrumentación , Dispositivos Electrónicos Vestibles , Algoritmos , Diseño de Equipo , Frecuencia Cardíaca/fisiología , Humanos , Monitoreo Fisiológico/métodos , Frecuencia Respiratoria/fisiología
13.
Clin Med (Lond) ; 2020 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-32354733

RESUMEN

There has been the need to make major modifications to the way cardiology is practised in light of the COVID-19 pandemic. There has also been the need to recognise the complex cardiovascular manifestations and complications of COVID-19. In this article we provide guidance on the management of cardiac patients without COVID-19 in the current pandemic as well as patients with cardiac disease and COVID-19 and patients with cardiac complications of COVID-19. There is also a focus on indications and interpretation of commonly performed cardiac investigations in the setting of COVID-19. References are included from a number of specialist societies and groups.

14.
Proc Mach Learn Res ; 126: 97-120, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33649743

RESUMEN

Blood pressure monitoring is an essential component of hypertension management and in the prediction of associated comorbidities. Blood pressure is a dynamic vital sign with frequent changes throughout a given day. Capturing blood pressure remotely and frequently (also known as ambulatory blood pressure monitoring) has traditionally been achieved by measuring blood pressure at discrete intervals using an inflatable cuff. However, there is growing interest in developing a cuffless ambulatory blood pressure monitoring system to measure blood pressure continuously. One such approach is by utilizing bioimpedance sensors to build regression models. A practical problem with this approach is that the amount of data required to confidently train such a regression model can be prohibitive. In this paper, we propose the application of the domain-adversarial training neural network (DANN) method on our multitask learning (MTL) blood pressure estimation model, allowing for knowledge transfer between subjects. Our proposed model obtains average root mean square error (RMSE) of 4.80 ± 0.74 mmHg for diastolic blood pressure and 7.34 ± 1.88 mmHg for systolic blood pressure when using three minutes of training data, 4.64 ± 0.60 mmHg and 7.10 ± 1.79 respectively when using four minutes of training data, and 4.48±0.57 mmHg and 6.79±1.70 respectively when using five minutes of training data. DANN improves training with minimal data in comparison to both directly training and to training with a pretrained model from another subject, decreasing RMSE by 0.19 to 0.26 mmHg (diastolic) and by 0.46 to 0.67 mmHg (systolic) in comparison to the best baseline models. We observe that four minutes of training data is the minimum requirement for our framework to exceed ISO standards within this cohort of patients.

15.
IEEE Trans Biomed Circuits Syst ; 13(6): 1723-1735, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31603828

RESUMEN

Continuous and beat-to-beat monitoring of blood pressure (BP), compared to office-based BP measurement, provides significant advantages in predicting future cardiovascular disease. Traditional BP measurement methods are based on a cuff, which is bulky, obtrusive and not applicable to continuous monitoring. Measurement of pulse transit time (PTT) is one of the prominent cuffless methods for continuous BP monitoring. PTT is the time taken by the pressure pulse to travel between two points in an arterial vessel, which is correlated with the BP. In this paper, we present a new cuffless BP method using an array of wrist-worn bio-impedance sensors placed on the radial and the ulnar arteries of the wrist to monitor the arterial pressure pulse from the blood volume changes at each sensor site. BP is accurately estimated by using AdaBoost regression model based on selected arterial pressure pulse features such as transit time, amplitude and slope of the pressure pulse, which are dependent on the cardiac activity and the vascular properties of the wrist arteries. A separate model is developed for each subject based on calibration data to capture the individual variations of BP parameters. In this pilot study, data was collected from 10 healthy participants with age ranges from 18 to 30 years after exercising using our custom low-noise bio-impedance sensing hardware. Post-exercise BP was accurately estimated with an average correlation coefficient and root mean square error (RMSE) of 0.77 and 2.6 mmHg for the diastolic BP and 0.86 and 3.4 mmHg for the systolic BP.


Asunto(s)
Determinación de la Presión Sanguínea/instrumentación , Análisis de la Onda del Pulso/instrumentación , Muñeca/fisiología , Adulto , Impedancia Eléctrica , Femenino , Voluntarios Sanos , Humanos , Masculino , Proyectos Piloto , Prueba de Estudio Conceptual , Análisis de Regresión , Dispositivos Electrónicos Vestibles , Adulto Joven
16.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 376-381, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31945919

RESUMEN

Continuous monitoring of respiration and heart pressure pulse waves generated by lung and heart movements is essential in the diagnosis and management of cardiovascular and lung diseases. Traditional methods in measuring these physiological signals are not convenient for long-term monitoring during daily activities and sleeping due to their use of long wires and/or face masks, and leading to patients having to spend long duration in clinics while undergoing supervised monitoring. In this paper, we present a new method to measure global chest physiological signals using small-sized smart band-age like patches placed at different locations of the chest. The introduced patches communicate with each other using human body and detect small variations in the bio-Impedance (Bio-Z) depending on the mechanical heart and lung movements, where one patch injects an AC current from one side of the chest and several Bio-Z sensors measure the voltage difference across different locations of the chest. In order to prevent usage of long wires and increase convenience for wearable applications, electrical connection between current injection and Bio-Z sensing patches are eliminated. Independent component analysis is used to separate sources of physiological observations and improve accuracy of the system. We show that the presented system can successfully detect respiration rate and heart rate with an average error of 4.86% (less than 1 breath per minute) and 1.86% (less than 2 beats per minute) respectively tested on 6 healthy subjects over 6 minutes of data collection for each subject.


Asunto(s)
Corazón , Tórax , Impedancia Eléctrica , Frecuencia Cardíaca , Humanos , Respiración
17.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 6569-6573, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31947347

RESUMEN

Accurate measurement of the heart pulse waveform based on blood volume changes inside the arteries is crucial for reliable estimation of hemodynamic parameters such as blood pressure and cardiac output. Placement of blood volume sensors such as bio-impedance sensors close to the arterial sites is essential for the accurate measurement of the pulse waveform. The effect of sensor location relative to the wrist arteries on the pulse waveform had not been studied previously on human subjects. In this paper, we explore the effect of arterial and off-arterial placement of the bio-impedance sensor on important pulse waveform features such as pulse transit time (PTT), which is the travel time of the arterial pressure pulse between two sensors, and diastolic peak error (DPE), a measure of pulse signal sharpness. Placing the current injection and voltage sensing electrodes of a bio-impedance sensor on the radial artery provide greater accuracy for such features. We find that arterial PTT has a significantly lower standard deviation compared to off-arterial PTT indicating better signal quality. Similarly, we observe that DPE is much smaller for arterial bio-impedance which confirms our expectations. Based on these features, the location of the artery can be determined using an array of sensors placed around the artery.


Asunto(s)
Determinación de la Presión Sanguínea , Análisis de la Onda del Pulso , Presión Sanguínea , Impedancia Eléctrica , Humanos , Arteria Radial
18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 4313-4317, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30441308

RESUMEN

Robust sensing is one of the main challenges for wearable physiological monitoring because of the high dependency on the placement of electrodes on the body, retaining suitable contact between electrodes and skin, and the effect of motion artifacts. In this paper, we present a wrist-worn strap that includes a 2-D array of 48 miniature electrodes covering the bottom side of the wrist with good contact with the skin. Good skin contact directly impacts the sensing robustness. The array provides local measurements between adjacent electrodes that span the whole bottom side of the wrist with an area of 6.25×4.60 cm for robust sensing. The array allows for the automatic selection of the correct electrodes at the right location regardless of changes in the device placement on the wrist. In addition, using a large number of electrodes over a large area on the wrist ensures continuous contact of some electrodes with the skin during motion since all of the electrodes will not lose contact with the skin at the same time. We measured the electrode-skin impedance of the fabricated electrodes versus frequency and compared to other types of electrodes. We demonstrated good contact between all electrodes of the array and the skin by measuring electrode-skin impedance less than 10 k$\Omega$ at 16 kHz for all locations on the wrist strap. We also conducted measurements of impedance while the wearer was bending the wrist to validate the continuous contact of at least a subset of electrodes with the skin during such movements.


Asunto(s)
Muñeca , Artefactos , Impedancia Eléctrica , Electrodos , Humanos , Monitoreo Fisiológico
19.
ESC Heart Fail ; 5(6): 1159-1164, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30175905

RESUMEN

AIMS: This analysis evaluates gender differences in the Egyptian cohort of patients hospitalized for acute heart failure (AHF) in the European Society of Cardiology Heart Failure Long-Term Registry. METHODS AND RESULTS: From April 2011 to September 2014, 1634 patients hospitalized with AHF were enrolled by 20 hospitals all over Egypt. Of these patients, 1112 (68%) patients were male and 522 (32%) were female. Women presented with a higher admission systolic blood pressure and resting heart rate. Compared with men, women had a higher body mass index (32.5 ± 9.0 vs. 29.3 ± 4.9, P < 0.001), more frequent atrial fibrillation (34.7% vs. 22.4%, P < 0.001), and anaemia defined by haemoglobin < 12 g/dL (83.1% vs. 58.4%, P < 0.001). Women were more likely to present with heart failure with preserved ejection fraction (29.7% vs. 10.6%, P < 0.001). Women had more frequent diabetes mellitus (48.1% vs. 41.6%, P < 0.05) and hypertension (48.7% vs. 39.3%, P < 0.001) than had men, whereas smoking was rare among them (8.8% vs. 82.9%, P < 0.005). There was no significant difference in the primary aetiology of heart failure between both sexes. ACE inhibitors, beta-blockers, mineralocorticoid receptor antagonists, antiplatelets, statins, and nitrates were less frequently prescribed to women, whereas they more often received digoxin, amiodarone, anticoagulants, and calcium channel blockers. There was no significant difference in in-hospital (5.7% vs. 4.6%, P = 0.39) and 1 year mortality (27.9% vs. 25.9%, P = 0.48) between women and men, respectively. CONCLUSIONS: Men and women with AHF differ significantly in baseline clinical characteristics and management but not in adverse outcomes. These findings emphasize the importance of individualized management and need for more comprehensive recruitment of women in clinical trials.


Asunto(s)
Cardiología , Insuficiencia Cardíaca/etnología , Pacientes Internos/estadística & datos numéricos , Sistema de Registros , Sociedades Médicas , Egipto/etnología , Europa (Continente)/epidemiología , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/terapia , Humanos , Masculino , Persona de Mediana Edad , Morbilidad , Estudios Prospectivos , Distribución por Sexo , Factores Sexuales , Factores de Tiempo
20.
Artículo en Inglés | MEDLINE | ID: mdl-31312808

RESUMEN

Continuous blood pressure (BP) monitoring is essential for diagnosis and management of cardiovascular disorders. Currently, BP is measured using cuff-based methods, which are obtrusive and not suitable for continuous monitoring. Estimation of BP using pulse transit time (PTT) is a prominent method that eliminates the need for a cuff. In this paper, we present a new method to estimate BP based on PTT measurements from an array of 2×2 bio-impedance sensors placed on the wrist, which can be integrated into a small wearable device such as a smart watch for continuous BP monitoring. Diastolic and systolic BP were estimated using AdaBoost regression model based on PTT features extracted from the wrist bio-impedance signals. Data was collected from three participants using our custom bio-impedance sensors. Our method can estimate BP accurately with correlation coefficient, mean absolute error (MAE) and standard deviation (STD) of 0.92, 1.71 and 2.46 mmHg for the diastolic BP and 0.94, 2.57 and 4.35 mmHg for the systolic BP.

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