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Letteratura scientifica selezionata sul tema "Cardiac health measurements"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 1 febbraio 2022

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Articoli di riviste sul tema "Cardiac health measurements"

Geelhoed, Miranda J. J., Sonja P. E. Snijders, Veronica E. Kleyburg-Linkers, Eric A. P. Steegers, Lennie van Osch-Gevers e Vincent W. V. Jaddoe. "Reliability of echocardiographic measurements of left cardiac structures in healthy children". Cardiology in the Young 19, n. 5 (20 agosto 2009): 494–500. http://dx.doi.org/10.1017/s1047951109990862.

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AbstractBackgroundEchocardiographic measurements are widely used as outcomes of different studies. The aim of this study was to assess intraobserver and interobserver reliability of echocardiographic measurements in healthy children.Materials and methodsWe studied 28 children, with a median age of 7.5 years, and inter-quartile range from 3 to 11 years. Intraobserver and interobserver reliability were assessed by repeated measurements of the diameters of the aortic root, the left atrium, and left ventricular end-diastolic structure. We also measured the ventricular end-diastolic septal thickness and the end-diastolic thickness of the left ventricular posterior wall. We calculated intraclass correlation coefficients, with corresponding 95% confidence intervals, and computed Bland and Altman plots, permitting us to derive limits of agreement plus or minus 2 standard deviations for the mean differences in cardiac measurements.ResultsWe found high intraobserver and interobserver intraclass correlation coefficient, ranging from 0.91 for ventricular septal thickness, with 95% confidence intervals from 0.78 to 0.96, to 0.99 for the diameter of the aortic root, 95% confidence interval from 0.97 to 1.00. Limits of agreement in the Bland and Altman plots ranged from zero millimetres for left ventricular end-diastolic posterior wall thickness to 1.60 millimeters (6.3%) for left atrial diameter.ConclusionsOur study demonstrated good repeatability and reproducibility for ultrasonic measurements of left cardiac structures in children, showing that values obtained for measurement of these structures in both clinical and epidemiological research projects can be confidently accepted.

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Abellán-Aynés, Oriol, Pedro Manonelles e Fernando Alacid. "Cardiac Parasympathetic Withdrawal and Sympathetic Activity: Effect of Heat Exposure on Heart Rate Variability". International Journal of Environmental Research and Public Health 18, n. 11 (31 maggio 2021): 5934. http://dx.doi.org/10.3390/ijerph18115934.

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Background: Research on heart rate variability has increased in recent years and the temperature has not been controlled in some studies assessing repeated measurements. This study aimed to analyze how heart rate variability may change based on environmental temperature during measurement depending on parasympathetic and sympathetic activity variations. Methods: A total of 22 volunteers participated in this study divided into an experimental (n = 12) and control group (n = 10). Each participant was assessed randomly under two different environmental conditions for the experimental group (19 °C and 35 °C) and two identical environmental conditions for the control group (19 °C). During the procedure, heart rate variability measurements were carried out for 10 min. Results: Significantly changes were observed for time and frequency domains as well as Poincaré plot variables after heat exposure (p < 0.05). These findings were not observed in the control group, whose conditions between measurements did not change. Conclusions: The reduction of heart rate variability due to exposure to hot conditions appears to be produced mostly by a parasympathetic withdrawal rather than a sympathetic activation. Therefore, if consecutive measurements have to be carried out, these should always be done under the same temperature conditions.

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Firstenberg, Michael S., Neil L. Greenberg, Mario J. Garcia, Annitta J. Morehead, Lisa A. Cardon, Allan L. Klein e James D. Thomas. "Internet-based transfer of cardiac ultrasound images". Journal of Telemedicine and Telecare 6, n. 3 (1 giugno 2000): 168–71. http://dx.doi.org/10.1258/1357633001935275.

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A drawback to large-scale multicentre studies is the time required for the centralized evaluation of diagnostic images. We evaluated the feasibility of digital transfer of echocardiographic images to a central laboratory for rapid and accurate interpretation. Ten patients undergoing trans-oesophageal echocardiographic scanning at three sites had representative single images and multiframe loops stored digitally. The images were analysed in the ordinary way. All images were then transferred via the Internet to a central laboratory and reanalysed by a different observer. The file sizes were 1.5-72 MByte and the transfer rates achieved were 0.6-4.8 Mbit/min. Quantitative measurements were similar between most on-site and central laboratory measurements (all P > 0.25), although measurements differed for left atrial width and pulmonary venous systolic velocities (both P < 0.05). Digital transfer of echocardiographic images and data to a central laboratory may be useful for multicentre trials.

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Wetzel, Glenn T., Fuhua Chen, William F. Friedman e Thomas S. Klitzner. "Calcium Current Measurements in Acutely Isolated Neonatal Cardiac Myocytes". Pediatric Research 30, n. 1 (luglio 1991): 83–88. http://dx.doi.org/10.1203/00006450-199107000-00017.

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WETZEL, GLENN T., FUHUA CHEN, WILLIAM F. FRIEDMAN e THOMAS S. KLITZNER. "Calcium Current Measurements in Acutely Isolated Neonatal Cardiac Myocytes". Pediatric Research 30, n. 1 (luglio 1991): 83???88. http://dx.doi.org/10.1203/00006450-199107010-00015.

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Renner, LE, e LT Meyer. "Injectate port selection affects accuracy and reproducibility of cardiac output measurements with multiport thermodilution pulmonary artery catheters". American Journal of Critical Care 3, n. 1 (1 gennaio 1994): 55–61. http://dx.doi.org/10.4037/ajcc1994.3.1.55.

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OBJECTIVE: To compare the accuracy and reproducibility of thermodilution cardiac output measurements obtained from the injectate and infusion ports of a multilumen pulmonary artery catheter. The thermodilution results were compared with an independent measure of flow obtained from an electromagnetic flow meter. METHODS: In an experimental study conducted at an animal research laboratory of a health sciences university, two virgin western breed ewes were surgically instrumented with an inferior vena cava occluder, which reduced venous return and thus lowered cardiac output, and an ascending aortic electromagnetic flow probe, which provided an independent reference measure of cardiac output. On the day of study, a multilumen pulmonary artery catheter was inserted. Cardiac output was manipulated over a range of 2.9 to 12.1 L/min with i.v. isoproterenol or inferior vena cava occlusion. Approximately 30 simultaneous thermodilution and electromagnetic flow meter measurements of cardiac output were obtained from both the infusion and injectate ports in each of the two subjects. RESULTS: Correlation coefficients were lower and standard error of the estimates was higher for the infusion port (r = .83; SEE = 1.19 L/min) vs the injectate port (r = .94; SEE = .74 L/min), indicating reduced reproducibility with infusion port thermodilution cardiac output determinations. Accuracy was also adversely influenced in the infusion port results. The linear regression for the infusion port data intercepted the Y axis at +2.64 L/min, indicating significant overestimation of cardiac output at flows of less than 5 L/min and underestimation of flow when cardiac output exceeded 8 L/min. CONCLUSIONS: The use of the infusion port for the measurement of thermodilution cardiac output measurements may result in nonreproducible and inaccurate results.

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Doi, Matsuyuki, Koji Morita e Kazuyuki Ikeda. "Frequently repeated fick cardiac output measurements during anesthesia". Journal of Clinical Monitoring 6, n. 2 (aprile 1990): 107–12. http://dx.doi.org/10.1007/bf02828286.

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D’Mello, Skoric, Xu, Roche, Lortie, Gagnon e Plant. "Real-Time Cardiac Beat Detection and Heart Rate Monitoring from Combined Seismocardiography and Gyrocardiography". Sensors 19, n. 16 (8 agosto 2019): 3472. http://dx.doi.org/10.3390/s19163472.

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Cardiography is an indispensable element of health care. However, the accessibility of at-home cardiac monitoring is limited by device complexity, accuracy, and cost. We have developed a real-time algorithm for heart rate monitoring and beat detection implemented in a custom-built, affordable system. These measurements were processed from seismocardiography (SCG) and gyrocardiography (GCG) signals recorded at the sternum, with concurrent electrocardiography (ECG) used as a reference. Our system demonstrated the feasibility of non-invasive electro-mechanical cardiac monitoring on supine, stationary subjects at a cost of $100, and with the SCG–GCG and ECG algorithms decoupled as standalone measurements. Testing was performed on 25 subjects in the supine position when relaxed, and when recovering from physical exercise, to record 23,984 cardiac cycles at heart rates in the range of 36–140 bpm. The correlation between the two measurements had r2 coefficients of 0.9783 and 0.9982 for normal (averaged) and instantaneous (beat identification) heart rates, respectively. At a sampling frequency of 250 Hz, the average computational time required was 0.088 s per measurement cycle, indicating the maximum refresh rate. A combined SCG and GCG measurement was found to improve accuracy due to fundamentally different noise rejection criteria in the mutually orthogonal signals. The speed, accuracy, and simplicity of our system validated its potential as a real-time, non-invasive, and affordable solution for outpatient cardiac monitoring in situations with negligible motion artifact.

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Jarolim, Petr, Purvish P. Patel, Michael J. Conrad, Lei Chang, Vojtech Melenovsky e David H. Wilson. "Fully Automated Ultrasensitive Digital Immunoassay for Cardiac Troponin I Based on Single Molecule Array Technology". Clinical Chemistry 61, n. 10 (1 ottobre 2015): 1283–91. http://dx.doi.org/10.1373/clinchem.2015.242081.

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Abstract BACKGROUND The association between increases in cardiac troponin and adverse cardiac outcomes is well established. There is a growing interest in exploring routine cardiac troponin monitoring as a potential early indicator of adverse heart health trends. Prognostic use of cardiac troponin measurements requires an assay with very high sensitivity and outstanding analytical performance. We report development and preliminary validation of an investigational assay meeting these requirements and demonstrate its applicability to cohorts of healthy individuals and patients with heart failure. METHODS On the basis of single molecule array technology, we developed a 45-min immunoassay for cardiac troponin I (cTnI) for use on a novel, fully automated digital analyzer. We characterized its analytical performance and measured cTnI in healthy individuals and heart failure patients in a preliminary study of assay analytical efficacy. RESULTS The assay exhibited a limit of detection of 0.01 ng/L, a limit of quantification of 0.08 ng/L, and a total CV of 10% at 2.0 ng/L. cTnI concentrations were well above the assay limit of detection for all samples tested, including samples from healthy individuals. cTnI was significantly higher in heart failure patients, and exhibited increasing median and interquartile concentrations with increasing New York Heart Association classification of heart failure severity. CONCLUSIONS The robust 2-log increase in sensitivity relative to contemporary high-sensitivity cardiac troponin immunoassays, combined with full automation, make this assay suitable for exploring cTnI concentrations in cohorts of healthy individuals and for the potential prognostic application of serial cardiac troponin measurements in both apparently healthy and diseased individuals.

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Collins, C., S. Drew, J. Holberton e C. Calado. "Reference Echocardiographic Measurements in Very Low Birth Weight Preterm Infants". American Journal of Perinatology 36, n. 03 (6 agosto 2018): 303–10. http://dx.doi.org/10.1055/s-0038-1667070.

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Background Echocardiography is an important technique in neonatal care. The heart of a premature baby is known to be different from that of a term baby, and there is a paucity of literature regarding reference cardiac measurements for this population, especially for the very low birth weight (VLBW) infants. Objective We aimed to present reference values for echocardiography in VLBW preterm infants. Study Design This was a retrospective observational study taking place over an 11-year period. We collected data from the reports of echocardiographic examinations performed in a population of preterm infants born with gestational age ≤ 32 weeks and birth weight (BW) ≤ 1,500 g in the first week of life. Results Our study population included 1,244 preterm infants. We found BW to be an adequate and practical variable to use in relation to the cardiac measurements. We propose reference values for seven cardiac measurements presented in tables for each 100 g weight subgroup. Conclusion Our study, to the best of our knowledge, has the largest sample of VLBW preterm infants and provides easy-to-use information on cardiac measurements by echocardiography for both pediatric cardiologists and neonatologists.

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Tesi sul tema "Cardiac health measurements"

Cathelyn, Jim, e L. Lee Glenn. "Effect of Ambient Temperature and Cardiac Stability on Two Methods of Cardiac Output Measurement". Digital Commons @ East Tennessee State University, 1999. https://dc.etsu.edu/etsu-works/7534.

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The dependence of cardiac output measurement precision on ambient temperature and cardiac output stability was assessed by concurrent continuous and bolus thermodilution methods in postoperative cardiac surgery patients. The degree of agreement between the two methods was depended on room temperature (0.1 L/min for each degree below 25 degrees C). The agreement was also closer in trials where cardiac output was stable (< 10% variation). The continuous thermodilution method shows sufficient agreement with the bolus method for use in critical care; however, improved precision of cardiac output thermodilution measurements can be achieved by use of correction factors for cardiac instability and for ambient temperature.

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Celik, Numan. "Wireless graphene-based electrocardiogram (ECG) sensor including multiple physiological measurement system". Thesis, Brunel University, 2017. http://bura.brunel.ac.uk/handle/2438/15698.

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In this thesis, a novel graphene (GN) based electrocardiogram (ECG) sensor is designed, constructed and tested to validate the concept of coating GN, which is a highly electrically conductive material, on Ag substrates of conventional electrodes. The background theory, design, experiments and results for the proposed GN-based ECG sensor are also presented. Due to the attractive electrical and physical characteristics of graphene, a new ECG sensor was investigated by coating GN onto itself. The main focus of this project was to examine the effect of GN on ECG monitoring and to compare its performance with conventional methods. A thorough investigation into GN synthesis on Ag substrate was conducted, which was accompanied by extensive simulation and experimentation. A GN-enabled ECG electrode was characterised by Raman spectroscopy, scanning electron microscopy along with electrical resistivity and conductivity measurements. The results obtained from the GN characteristic experimentation on Raman spectroscopy, detected a 2D peak in the GN-coated electrode, which was not observed with the conventional Ag/AgCl electrode. SEM characterisation also revealed that a GN coating smooths the surface of the electrode and hence, improves the skin-to-electrode contact. Furthermore, a comparison regarding the electrical conductivity calculation was made between the proposed GN-coated electrodes and conventional Ag/AgCl ones. The resistance values obtained were 212.4 Ω and 28.3 Ω for bare and GN-coated electrodes, respectively. That indicates that the electrical conductivity of GN-based electrodes is superior and hence, it is concluded that skin-electrode contact impedance can be lowered by their usage. Additional COMSOL simulation was carried out to observe the effect of an electrical field and surface charge density using GN-coated and conventional Ag/AgCl electrodes on a simplified human skin model. The results demonstrated the effectiveness of the addition of electrical field and surface charge capabilities and hence, coating GN on Ag substrates was validated through this simulation. This novel ECG electrode was tested with various types of electrodes on ten different subjects in order to analyse the obtained ECG signals. The experimental results clearly showed that the proposed GN-based electrode exhibits the best performance in terms of ECG signal quality, detection of critical waves of ECG morphology (P-wave, QRS complex and T-wave), signal-to-noise ratio (SNR) with 27.0 dB and skin-electrode contact impedance (65.82 kΩ at 20 Hz) when compared to those obtained by conventional a Ag/AgCl electrode. Moreover, this proposed GN-based ECG sensor was integrated with core body temperature (CBT) sensor in an ear-based device, which was designed and printed using 3D technology. Subsequently, a finger clipped photoplethysmography (PPG) sensor was integrated with the two-sensors in an Arduino based data acquisition system, which was placed on the subject's arm to enable a wearable multiple physiological measurement system. The physiological information of ECG and CBT was obtained from the ear of the subject, whilst the PPG signal was acquired from the finger. Furthermore, this multiple physiological signal was wirelessly transmitted to the smartphone to achieve continuous and real-time monitoring of physiological signals (ECG, CBT and PPG) on a dedicated app developed using the Java programming language. The proposed system has plenty of room for performance improvement and future development will make it adaptabadaptable, hence being more convenient for the users to implement other applications than at present.

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Jones, Nicole L. "Comparison of physical activity assessment methods among Phase III cardiac rehabilitation participants". Virtual Press, 2006. http://liblink.bsu.edu/uhtbin/catkey/1339152.

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Physical inactivity is a significant health concern for individuals in the United States, and is especially an issue for those with a history of coronary artery disease. Increased physical activity is encouraged for those who are participants in Phase III cardiac rehabilitation to promote a healthy lifestyle after a cardiac event. The purpose of the study was to assess and characterize the physical activity levels of Phase III cardiac patients. Other objectives of this study were to compare various forms of physical activity assessment and compare the activity levels of the cardiac rehabilitation participants with other populations. Comparisons of three physical activity devices were analyzed as well as activity levels on rehab and non-rehab days. Those who participated in home exercise vs. those who did not do home exercise were compared as well as those who were retired vs. those who were employed. Subject inclusion criteria included Phase III cardiac patients who were 40-69 years of age and who attended rehab a minimum of two days per week. The subjects were required to wear a pedometer and accelerometer for at least 12 days and complete a questionnaire following the trial. The mean ± S. D. for age, height, weight and BMI of the subjects was 59.4±8.2 years, 69.1±3.1 inches, 200.9±41.8 lbs., and 29.4±4.8 kg/m2 respectively. The Lifecorder, ActiGraph and International Physical Activity Questionnaire (IPAQ) were used to measure physical activity levels of the Phase III cardiac patients. The IPAQ did not correlate well with the Lifecorder or ActiGraph in assessing physical activity in Phase III cardiac patients (R=0.251, P=0.226-ActiGraph and R=0.280, P=0.175-Lifecorder), however, the Lifecorder and the ActiGraph had a significant correlation coefficient with one another (R=0.83, P<0.001). Rehab vs. non-rehab day data as well as rehab session and non-rehab session physical activity levels were compared among the subjects. On a rehab day, subjects took 9,770±3132 steps/day, which was significantly higher than what they took on a non-rehab day, 5,404±2843 steps/day. Those who did not exercise at home accumulated on average 8,194±2912 steps/day on a rehab day, while on a non-rehab day they accumulated 3,475±1579 steps/day (P<0.001). Those who did exercise at home, took 10,883±2856 steps/day on a rehab day, while on a non rehab day they took 6,767±2768 steps/day (P<0.001). Those who were employed were more active than those who were retired. In conclusion, Phase III cardiac rehabilitation is an effective way to increase physical activity levels of those with a history of coronary artery disease. All participants in Phase III cardiac rehabilitation should be encouraged to come into the center-based facility at least 4-5 days per week or implement a home exercise program into their weekly regimen.
School of Physical Education, Sport, and Exercise Science

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Miller, Angela Nicole Roberts. "The CaReS Battery: Measuring Stages of Change in Cardiac Rehabilitation through the Development of a Targeted Instrument". Kent State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=kent1279478756.

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Klein, Ran. "Precise rubidium-82 infusion system for cardiac perfusion measurement using three-dimensional positron emission tomography". Thesis, University of Ottawa (Canada), 2005. http://hdl.handle.net/10393/27144.

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Introduction. Quantitative myocardial perfusion measurements using positron emission tomography (PET) can be improved by introducing diagnostic tracers at a constant rate of activity. 82Rb can be produced cost effectively by eluting a 82Sr/82Rb generator with saline; however, it exhibits an undesirable, but reproducible, activity rate variation. Previously, a threshold-comparison algorithm controlled saline flow through either generator or bypass line using an on/off valve, to simulate constant-activity elutions. Methods. In this work a mechanical system and control software is developed to control tracer infusion. The valve is cycled at 5Hz and its duty-cycle controlled by a predictive-corrective algorithm in order to reduce measurable activity rate fluctuations. Results. Precision increases (RMS error improves from >40% to ∼14%) as does the range of relative activities that can be eluted from the generator. Conclusion. The proposed method demonstrates superior precision and flexibility. However, further tests must be conducted to ensure that the precision of the system does not deteriorate over time.

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Sandri, Gustavo Luiz. "Automated non-contact heart rate measurement using conventional video cameras". reponame:Repositório Institucional da UnB, 2016. http://dx.doi.org/10.26512/2016.02.D.21118.

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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Elétrica, 2016.
Conforme o sangue flui através do corpo de um indivíduo, ele muda a forma como a luz é irradiada pela pele, pois o sangue absorve luz de forma diferente dos outros tecidos. Essa sutil variação pode ser capturada por uma câmera e ser usada para monitorar a atividade cardíaca de uma pessoa. O sinal capturado pela câmera é uma onda que representa as variações de tonalidade da pele ao longo do tempo. A frequência dessa onda é a mesma frequência na qual o coração bate. Portanto, o sinal capturado pela câmera pode ser usado para estimar a taxa cardíaca de uma pessoa. Medir o pulso cardíaco remotamente traz mais conforto pois evita o uso de eletrodos. Também permite o monitoramento de uma pessoa de forma oculta para ser empregado em um detector de mentira, por exemplo. Neste trabalho nós propomos dois algoritmos para a estimação da taxa cardíaca sem contato usando câmeras convencionais sob iluminação não controlada. O primeiro algoritmo proposto é um método simples que emprega um detector de face que identifica a face da pessoa sendo monitorada e extrai o sinal gerado pelas mudanças no tom da pele devido ao fluxo sanguíneo. Este algoritmo emprega um filtro adaptativo para aumentar a energia do sinal de interesse em relação ao ruído. Nós mostramos que este algoritmo funciona muito bem para vídeos com pouco movimento. O segundo algoritmo que propomos é uma melhora do primeiro para torná-lo mais robusto a movimentos. Nós modificamos o método usado para definir a região de interesse. Neste algoritmo é utilizado um detector de pele para eliminar pixels do plano de fundo do vídeo, os frames dos vídeos são divididos em micro-regiões que são rastreados com um algoritmo de fluxo ótico para compensar os movimentos e um algoritmo de clusterização é aplicado para selecionar automaticamente as melhores micro-regiões para efetuar a estimação da taxa cardíaca. Propomos também um esquema de filtragem temporal e espacial para reduzir o ruído introduzido pelo algoritmo de fluxo ótico. Comparamos os resultados dos nossos algoritmos com um oxímetro de dedo comercial e mostramos que eles funcionam bem para situações desafiadoras.
As the blood flows through the body of an individual, it changes the way that light is irradiated by the skin, because blood absorbs light differently than the remaining tissues. This subtle variation can be captured by a camera and be used to monitor the heart activity of a person. The signal captured by the camera is a wave that represents the changes in skin tone along time. The frequency of this wave is the same as the frequency by which the heart beats. Therefore, the signal captured by the camera could be used to estimate a person’s heart rate. This remote measurement of cardiac pulse provides more comfort as it avoids the use of electrodes or others devices attached to the body. It also allows the monitoring of a person in a canceled way to be employed in lie detectors, for example. In this work we propose two algorithms for non-contact heart rate estimation using conventional cameras under uncontrolled illumination. The first proposed algorithm is a simple approach that uses a face detector to identify the face of the person being monitored and extract the signal generated by the changes in the skin tone due to the blood flow. This algorithm employs an adaptive filter to boost the energy of the interest signal against noise. We show that this algorithm works very well for videos with little movement. The second algorithm we propose is an improvement of the first one to make it more robust to movements. We modify the approach used to define the region of interest. In this algorithm we employ a skin detector to eliminate pixels from the background, divide the frames in microregions that are tracked using an optical flow algorithm to compensate for movements and we apply a clustering algorithm to automatically select the best micro-regions to use for heart rate estimation. We also propose a temporal and spatial filtering scheme to reduce noise introduced by the optical flow algorithm. We compared the results of our algorithms to an off-the-shelf fingertip pulse oximeter and showed that they can work well under challenging situations.

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Kiviniemi, A. (Antti). "Measurement of cardiac vagal outflow by beat-to-beat R-R interval dynamics". Doctoral thesis, University of Oulu, 2006. http://urn.fi/urn:isbn:9514281896.

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Abstract Analysis of beat-to-beat heart rate variability (HRV) provides information of cardiac vagal outflow to the sinus node. Some methodological problems might, however, be involved in the analysis of cardiac vagal outflow from ambulatory Holter recordings, such as saturation, physical activity, and abrubt prolongations of R-R intervals unrelated to respiration. The purpose of this thesis was to assess the physiological basis of beat-to-beat HRV and to develop and assess new methods for the quantification of cardiac autonomic modulation from ambulatory Holter recordings. The study population consisted of 89 healthy volunteers (age 24 ± 4 years) and 590 patients with a recent acute myocardial infarction (AMI, age 61 ± 10 years). The relationship between R-R interval length and the high-frequency (HF) spectral power of the R-R intervals was assessed in 76 healthy subjects and 82 post-AMI patients. The effects of aerobic exercise training on the dynamics between R-R interval and HF power were evaluated by means of a controlled 8-week training intervention (n = 17). The effects of sympathetic activation and concomitant sympathetic and vagal outflow on beat-to-beat HR dynamics were studied in laboratory conditions (n = 13). A new method for quantifying beat-to-beat HRV from the R-R interval lengths where the relationship between HF power and R-R interval is most linear was developed to avoid the confounding effects of possible saturation, physical activity, and random R-R interval dynamics. The clinical significance of the new method was assessed in a series of 590 post-AMI patients. Saturated HF R-R interval dynamics, expressed as a lack of increase in HF power despite an increased R-R interval, was observed in 35 healthy subjects and 9 post-AMI patients. In the training study, 7 subjects out of a total of 17 had saturated HF power before the intervention. After the training period, 5 new cases of saturated HF power were observed. In laboratory conditions, co-activation of sympathetic and vagal outflow resulted in random R-R interval dynamics. In post-AMI patients, HF power analyzed exclusively from the R-R intervals where the relationship between the R-R interval and HF power was most linear (Vindex) predicted independently the occurrence of SCD among post-AMI patients, while traditionally analyzed HF power did not. In conclusion, the saturation of beat-to-beat HRV in ambulatory conditions is a common phenomenon. The prevalence of saturated HF power increases due to enhanced cardiac vagal outflow induced by aerobic training. Finally, the novel analysis of vagally mediated HRV (Vindex) provides unique information that cannot be obtained by traditional analysis of HF R-R interval dynamics.

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Jones, Jason L. "Pedometer intervention to increase physical activity of patients entering a maintenance cardiac rehabilitation program". Muncie, IN : Ball State University, 2009. http://cardinalscholar.bsu.edu/654.

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Taniguchi, Ryoji. "Combined measurements of cardiac troponin T and N-terminal pro-brain natriuretic peptide in patients with heart failure". Kyoto University, 2006. http://hdl.handle.net/2433/143842.

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Waldenborg, Micael. "Echocardiographic measurements at Takotsubo cardiomyopathy : transient left ventricular dysfunction". Doctoral thesis, Örebro universitet, Institutionen för hälsovetenskap och medicin, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-35798.

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Takotsubo cardiomyopathy (TTC) is a disease characterized by transient left ventricular (LV) dysfunction and typical wall motion abnormalities in apical parts, without obvious signs of coronary influence. Due to its elusive natural cause and the lack of clarified pathology, further studies are needed. Thirteen patients presented with an episode of TTC, and referred to Örebro University Hospital (USÖ), were prospectively included and investigated by comparisons made at onset (acute phase) against at follow-up three months later (recovery phase). Including echocardiographic measurements, focused on biventricular systolic long-axis function and conventional diastolic function (DF) variables. Systolic improvement was shown, while most DF data were unchanged, suggesting that TTC is mainly a systolic disease affecting both ventricles. Diagnosis should include multidisciplinary engagement, as TTC associates both with emotional stress and pathological markers of physiological stress. In this thesis, such approach was offered to the aforementioned patients; to see if a common denominator could be found, thus, contributing to better handling. Emotional state was assessed, along with an array of cardiac investigations in addition to echocardiography. Acutely, imbalance in the autonomic cardiac control was shown, as well as a trend toward posttraumatic stress, but specific findings allowing conclusions on differential diagnosis could not be demonstrated. By adding another 15 TTC patients (i.e. 28 in total), through collaboration with observers from USA, a retrospective echocardiographic analysis could be done to further study DF; concluding that TTC associates with impairment of conventional DF variables which tends to parallel the systolic recovery, in contrary to the initial result but in line with other causesof LV dysfunction. Magnetic resonance imaging (MRI) is another method of choice at TTC. The USÖ patients had cardiac MRI, thus, a retrospective analysis was done to investigate the effect on LV geometry, both echocardiographic and by MRI; suggesting that TTC is consistently associated with increased LV mass, due to a local impact that seems to follow the change in LVconcentric wall motion.

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Libri sul tema "Cardiac health measurements"

Bustin, Debra. Hemodynamic monitoring for critical care. Norwalk, Conn: Appleton-Century-Crofts, 1986.

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Interventional physiology rounds: Case studies in coronary pressure and flow for clinical practice. New York: Wiley-Liss, 1998.

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Demetriades, Demetrios, Leslie Kobayashi e Lydia Lam. Cardiac complications in trauma. Oxford University Press, 2015. http://dx.doi.org/10.1093/med/9780199687039.003.0062.

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Post-traumatic cardiac complications may occur after penetrating or blunt injuries to the heart or may follow severe extracardiac injuries. The majority of victims with penetrating injuries to the heart die at the scene and do not reach hospital care. For those patients who reach hospital care, an immediate operation, sometimes in the emergency room, cardiac injury repair, and cardiopulmonary resuscitation provide the only possibility of survival. Many patients develop perioperative cardiac complications such as acute cardiac failure, cardiac arrhythmias, coronary air embolism, and myocardial infarction. Some survivors develop post-operative functional abnormalities or anatomical defects, which may not manifest during the early post-operative period. It is essential that all survivors undergo detailed early and late cardiac evaluations. Blunt cardiac trauma encompasses a wide spectrum of injuries that includes asymptomatic myocardial contusion, arrhythmias, or cardiogenic shock to full-thickness cardiac rupture and death. Clinical examination, electrocardiograms, troponin measurements, and echocardiography are the cornerstone of diagnosis and monitoring of these patients. Lastly, some serious extracardiac traumatic conditions, such as traumatic pneumonectomy and severe traumatic brain injury, may result in cardiac complications. This may include tachyarrhythmias, cardiogenic shock, electrocardiographic changes, troponin elevations, heart failure, and cardiac arrest.

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Demetriades, Demetrios, Leslie Kobayashi e Lydia Lam. Cardiac complications in trauma. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199687039.003.0062_update_001.

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Lam, Lydia, Leslie Kobayashi e Demetrios Demetriades. Cardiac complications in trauma. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780199687039.003.0062_update_002.

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Lam, Lydia, Leslie Kobayashi e Demetrios Demetriades. Cardiac complications in trauma. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780199687039.003.0062_update_003.

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Vincent, Jean-Louis. Ethical issues in cardiac arrest and acute cardiac care: a European perspective. Oxford University Press, 2015. http://dx.doi.org/10.1093/med/9780199687039.003.0013.

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The respiratory system is key to the management of patients with respiratory, as well as haemodynamic, compromise and should be monitored. The ventilator is more than just a machine that delivers gas; it is a true respiratory system monitoring device, allowing the measurement of airway pressures and intrinsic positive end-expiratory pressure and the plotting of pressure/volume curves. For effective and reliable monitoring, it is necessary to keep in mind the physiology, such as the alveolar gas equation, heart-lung interactions, the equation of movement, etc. Monitoring the respiratory system enables adaptation of not only respiratory management, but also haemodynamic management.

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Vincent, Jean-Louis. Ethical issues in cardiac arrest and acute cardiac care: a European perspective. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199687039.003.0013_update_001.

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A, Amini Amir, e Prince Jerry L, a cura di. Measurement of cardiac deformations from MRI: Physical and mathematical models. Dordrecht: Kluwer Academic Publishers, 2001.

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Sainz, Jorge G., e Bradley P. Fuhrman. Basic Pediatric Hemodynamic Monitoring. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780199918027.003.0005.

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Physiological monitoring using a variety of technological advances supplements, but does not replace, our ability to distinguish normal from abnormal physiology traditionally gleaned from physical examination. Pulse oximetry uses the wavelengths of saturated and unsaturated hemoglobin to estimate arterial oxygenation noninvasively. Similar technology included on vascular catheters provides estimation of central or mixed venous oxygenation and helps assess the adequacy of oxygen delivered to tissues. End-tidal carbon dioxide measurements contribute to the assessment of ventilation. Systemic arterial blood pressure and central venous pressure measurements help evaluate cardiac performance, including the impact of ventilatory support. Intra-abdominal pressure may increase as a result of intraluminal air or fluid, abnormal fluid collections within the peritoneal cavity, or abnormal masses. Increased pressure may impede venous return to the heart and compromise intra-abdominal organ perfusion. Pressure measurement guides related management decisions.

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Capitoli di libri sul tema "Cardiac health measurements"

Ravon, Gwladys, Yves Coudière, Angelo Iollo, Oliver Bernus e Richard D. Walton. "Issues in Modeling Cardiac Optical Mapping Measurements". In Functional Imaging and Modeling of the Heart, 457–65. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-20309-6_52.

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Hartikainen, Juha E. K., Kari U. O. Tahvanainen e Tom A. Kuusela. "Short-Term Measurement of Heart Rate Variability". In Clinical Guide to Cardiac Autonomic Tests, 149–76. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-017-1057-2_6.

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Hedman, Antti E., e Marek Malik. "Long-Term Measurement of Heart Rate Variability". In Clinical Guide to Cardiac Autonomic Tests, 195–238. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-017-1057-2_8.

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Page, Sally G. "Measurements of Structural Parameters in Cardiac Muscle". In Ciba Foundation Symposium 24 - Physiological Basis of Starling's Law of the Heart, 13–30. Chichester, UK: John Wiley & Sons, Ltd, 2008. http://dx.doi.org/10.1002/9780470720066.ch3.

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Johnston, A. "Techniques for the blood level measurement of cardiac drugs and their application". In Drugs for Heart Disease, 365–77. Boston, MA: Springer US, 1987. http://dx.doi.org/10.1007/978-1-4899-3294-5_13.

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Lopes, D. F., J. L. Marques e E. A. Castro. "A MCDA/GIS-Based Approach for Evaluating Accessibility to Health Facilities". In Computational Science and Its Applications – ICCSA 2021, 311–22. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-86973-1_22.

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AbstractAccess to health care services is a key concept in the formulation of health policies to improve the population’s health status and to mitigate inequities in health. Previous studies have significantly enhanced our understanding and knowledge of the role played by spatial distribution of health facilities in sustaining population health, with extensive research being devoted to the place-based accessibility theory, with special focus on the gravity-based methods. Although they represent a good starting point to analyse disparities across different regions, the results are not intelligible for policy-making purposes. Given the weaknesses of these methods and the multidimensional nature of the topic, this study intends to: (i) highlight the main measurements of access and their major challenges; and (ii) propose a framework based on multiple criteria decision analysis methods and GIS to appraise the population’s accessibility to health facilities. In particular, this framework is based on a new variant of the UTASTAR method, which requires decision makers and/or experts preference information, in the form of an ordinal ranking, similarly to the UTASTAR method, but to which cardinal information is also added. A numerical example is presented to illustrate the application of the proposed methodology.

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Wong, K. K. L., R. M. Kelso, S. G. Worthley, P. Sanders, J. Mazumdar e D. Abbott. "A Novel Measurement System for Cardiac Flow Analysis Applied to Phase Contrast Magnetic Resonance Imaging of the Heart". In IFMBE Proceedings, 596–99. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-03879-2_167.

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Fukuda, H., H. Yasuda, S. Shimokawa e M. Tamura. "The Oxygen Dependence of the Energy State of Cardiac Tissue: 3 1P-NMR and Optical Measurement of Myoglobin in Perfused Rat Heart". In Oxygen Transport to Tissue XI, 567–73. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4684-5643-1_63.

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Patil, H. G. Sandeep, Ajit N. Babu e P. S. Ramkumar. "Non-Invasive Data Acquisition and Measurement in Bio-Medical Technology". In Advances in Healthcare Information Systems and Administration, 27–45. IGI Global, 2016. http://dx.doi.org/10.4018/978-1-4666-9446-0.ch003.

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Non-invasive medical measurements have expanded into several types of diagnostic and monitoring activities in health care delivery. They are being used in handling a number of non-infectious diseases such as diabetes, asthma, hypertension, congestive heart failure, cardiac arrhythmia, etc., as well as infectious diseases such as cholera, malaria, etc.. Non-Invasive Medical Devices (NIMDs) are naturally preferred over invasive methods considering patient convenience, reduced patient risk, increased speed, and operational simplicity. However non-invasive methods are often perceived to be less accurate than their invasive counterparts. Over the last decade, technological advances and mathematical techniques have improved significantly, challenging this perception across the board. The chapter will discuss this important transformation in health care diagnostics and monitoring. The chapter will also provide further insight into some of the currently available non-invasive measurement products and explore how futuristic techniques and technology trends which have great potential to transform healthcare into a significantly different paradigm than the one we experience today.

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Patil, H. G. Sandeep, Ajit N. Babu e P. S. Ramkumar. "Non-Invasive Data Acquisition and Measurement in Bio-Medical Technology". In Medical Imaging, 253–71. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-0571-6.ch010.

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Non-invasive medical measurements have expanded into several types of diagnostic and monitoring activities in health care delivery. They are being used in handling a number of non-infectious diseases such as diabetes, asthma, hypertension, congestive heart failure, cardiac arrhythmia, etc., as well as infectious diseases such as cholera, malaria, etc. Non-Invasive Medical Devices (NIMDs) are naturally preferred over invasive methods considering patient convenience, reduced patient risk, increased speed, and operational simplicity. However non-invasive methods are often perceived to be less accurate than their invasive counterparts. Over the last decade, technological advances and mathematical techniques have improved significantly, challenging this perception across the board. The chapter will discuss this important transformation in health care diagnostics and monitoring. The chapter will also provide further insight into some of the currently available non-invasive measurement products and explore how futuristic techniques and technology trends which have great potential to transform healthcare into a significantly different paradigm than the one we experience today.

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Atti di convegni sul tema "Cardiac health measurements"

Pirozzi, M., F. Pietroni, S. Casaccia, L. Scalise e G. M. Revel. "Cardiac Activity Classification using an E-Health App for a Wearable Device". In 2018 IEEE International Symposium on Medical Measurements and Applications (MeMeA). IEEE, 2018. http://dx.doi.org/10.1109/memea.2018.8438674.

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Lee, Namheon, Michael D. Taylor, Kan N. Hor e Rupak K. Banerjee. "Non-Invasive Calculation of Energy Loss in Pulmonary Arteries Using 4D Phase Contrast MRI Measurement". In ASME 2012 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/sbc2012-80525.

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The recent development of energy based endpoints, to quantify the pathophysiology of congenital heart disease such as tetralogy of Fallot (TOF), requires accurate measurement of cardiac blood flow and pressure data. Consequently, invasive cardiac catheterization is required for those measurements. In this research we used 4D phase contrast magnetic resonance imaging (PC MRI) data to determine the pressure drop non-invasively. This enables us to obtain pressure-flow variation, which, in turn, allowed us to calculate energy loss along the branch pulmonary arteries (PA). Based on our result, we believe that the hemodynamic status of the PA of a subject can be non-invasively evaluated by both pressure drop and energy loss values along the PA.

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Córdova Aquino, Jacobo, e Hugo I. Medellín-Castillo. "A Passive Hybrid Model to Estimate the Elastic Performance of Left Ventricular Cardiac Fibres". In ASME 2019 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/imece2019-12124.

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Abstract The development of mathematical and numerical models of the human heart has become a matter of high relevance in the scientific community because of the difficulty of measuring the properties and performance of the cardiac tissue in vivo, and carrying out experimental tests under different healthy and pathological conditions. Several heart models have been proposed in the literature, but the results still differ from each other. In this paper, a new passive heart model to estimate the elastic behaviour of the left ventricular (LV) cardiac fibres is presented. The model is based on a hybrid approach that combines a theoretical approach to determine the equivalent material properties of each layer of the LV tissue, which represents an advantage with respect to other more elaborated or complex models, and an inverse finite element method (FEM) to determine the volume of the LV internal cavity under loading conditions. The proposed model uses the LV pressure and volume measurements along a real cardiac cycle as loading and target conditions, respectively. The results are analysed in terms of the elastic properties of the cardiac fibres and compared with the results obtained from other more complex and elaborated models reported in the literature. From this analysis it is observed that the new proposed model is reliable and able to estimate the elastic behaviour of the cardiac tissue.

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van der Horst, Arjen, Frits L. Boogaard, Marcel C. M. Rutten e Frans N. van de Vosse. "A 1D Wave Propagation Model of Coronary Flow in a Beating Heart". In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-53367.

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Due to recent developments in miniaturized sensors on guide-wires, assessment of coronary artery disease with intracoronary pressure and flow measurements has become available. However, direct quantification is still limited to the large epicardial vessels, which means that microvascular disease can only be determined from upstream measurements using an appropriate model of the vessels and their interaction with the cardiac muscle [1].

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Xu, Jiangtao, Jialu Wang, Minshun Wu e Ruizhi Zhang. "An accurate switched-capacitor heart resistance measurement for cardiac pacemaker". In 2016 IEEE Biomedical Circuits and Systems Conference (BioCAS). IEEE, 2016. http://dx.doi.org/10.1109/biocas.2016.7833838.

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Lieber, Samuel C., Nadine Aubry, Jayashree Pain, Gissela Diaz, Song-Jung Kim e Stephen S. Vatner. "Measurement of the Transverse Apparent Elastic Modulus in Mammalian Cardiac Myocytes". In ASME 2003 International Mechanical Engineering Congress and Exposition. ASMEDC, 2003. http://dx.doi.org/10.1115/imece2003-41469.

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Transverse mechanical properties of mammalian cardiac myocytes, was determined by using atomic force microscopy (AFM). The AFM can be used as a nano-indentation device allowing transverse stiffness measurements to be conducted on biological cells in a physiological environment. This enables real-time biomechanical and physiological processes to be monitored with nano-scale resolution. Cellular mechanical properties were determined by indenting the cell’s body, and analyzing the indentation data with classical infinitesimal strain theory (CIST). This calculation was accomplished by modeling the AFM probe as a blunted cone. The blunted cone geometry fits the AFM force indentation data well and was used to calculate the apparent elastic modulus of the cardiac myocyte body. The mechanical properties of male 344 x Brown Norway F1 hybrid (F344×BN) rat cells was measured and an apparent elastic modulus of 35.1 ± 0.7 kPa (n = 53) was calculated. Further studies are being conducted on myocytes isolated from aged hearts to determine whether age effects cardiac mechanical properties at the level of the single myocyte.

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Farrar, G. E., G. T. Gullberg e A. I. Veress. "Full Cardiac Cycle Strain Measurement Using Hyperelastic Warping, Application to Detecting Myocardial Dysfunction in Rat microPET Images". In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-53654.

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Assessments of regional heart wall deformation (wall motion, thickening, strain) are commonly used to evaluate left ventricular wall function in the clinical setting. Nuclear based imaging modalities such as PET and SPECT are commonly used to localize ischemic myocardial disease, and can identify impairment of cardiac function due to hypertrophic or dilated cardiomyopathies. Regional wall motion analysis in conjunction with global left ventricular (LV) ejection fraction is commonly used to assess systolic and diastolic function. The quantification of ventricular strains throughout the entire cardiac cycle provides valuable information that could be used to more effectively differentiate between diastolic and systolic dysfunction, as well as a more complete picture of overall cardiac performance.

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Ishay, Roni Ben, Scharf Shimon, Maya Herman e Chaim Yosefy. "Classification of Left Heart Functional Dimensions by Clustering Cardiac Echo-Doppler Measurements". In 2006 International Conference on Information Technology: Research and Education. IEEE, 2006. http://dx.doi.org/10.1109/itre.2006.381547.

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Kondruweit, M., N. Ebel, S. Kniesburges, M. Döllinger e M. Weyand. "Direct Ex Vivo Measurement of the Real Geometric Orifice Area to Assess the Hemodynamic Performance of Bioprosthetic Heart Valves". In 48th Annual Meeting German Society for Thoracic, Cardiac, and Vascular Surgery. Georg Thieme Verlag KG, 2019. http://dx.doi.org/10.1055/s-0039-1678991.

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Wiener, Thomas, Robert Arnold e Ernst Hofer. "On-line analysis of cardiac near field signals during electrophysiological experiments with heart preparations". In 2012 IEEE International Instrumentation and Measurement Technology Conference (I2MTC). IEEE, 2012. http://dx.doi.org/10.1109/i2mtc.2012.6229563.

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Rapporti di organizzazioni sul tema "Cardiac health measurements"

Treadwell, Jonathan R., James T. Reston, Benjamin Rouse, Joann Fontanarosa, Neha Patel e Nikhil K. Mull. Automated-Entry Patient-Generated Health Data for Chronic Conditions: The Evidence on Health Outcomes. Agency for Healthcare Research and Quality (AHRQ), marzo 2021. http://dx.doi.org/10.23970/ahrqepctb38.

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Background. Automated-entry consumer devices that collect and transmit patient-generated health data (PGHD) are being evaluated as potential tools to aid in the management of chronic diseases. The need exists to evaluate the evidence regarding consumer PGHD technologies, particularly for devices that have not gone through Food and Drug Administration evaluation. Purpose. To summarize the research related to automated-entry consumer health technologies that provide PGHD for the prevention or management of 11 chronic diseases. Methods. The project scope was determined through discussions with Key Informants. We searched MEDLINE and EMBASE (via EMBASE.com), In-Process MEDLINE and PubMed unique content (via PubMed.gov), and the Cochrane Database of Systematic Reviews for systematic reviews or controlled trials. We also searched ClinicalTrials.gov for ongoing studies. We assessed risk of bias and extracted data on health outcomes, surrogate outcomes, usability, sustainability, cost-effectiveness outcomes (quantifying the tradeoffs between health effects and cost), process outcomes, and other characteristics related to PGHD technologies. For isolated effects on health outcomes, we classified the results in one of four categories: (1) likely no effect, (2) unclear, (3) possible positive effect, or (4) likely positive effect. When we categorized the data as “unclear” based solely on health outcomes, we then examined and classified surrogate outcomes for that particular clinical condition. Findings. We identified 114 unique studies that met inclusion criteria. The largest number of studies addressed patients with hypertension (51 studies) and obesity (43 studies). Eighty-four trials used a single PGHD device, 23 used 2 PGHD devices, and the other 7 used 3 or more PGHD devices. Pedometers, blood pressure (BP) monitors, and scales were commonly used in the same studies. Overall, we found a “possible positive effect” of PGHD interventions on health outcomes for coronary artery disease, heart failure, and asthma. For obesity, we rated the health outcomes as unclear, and the surrogate outcomes (body mass index/weight) as likely no effect. For hypertension, we rated the health outcomes as unclear, and the surrogate outcomes (systolic BP/diastolic BP) as possible positive effect. For cardiac arrhythmias or conduction abnormalities we rated the health outcomes as unclear and the surrogate outcome (time to arrhythmia detection) as likely positive effect. The findings were “unclear” regarding PGHD interventions for diabetes prevention, sleep apnea, stroke, Parkinson’s disease, and chronic obstructive pulmonary disease. Most studies did not report harms related to PGHD interventions; the relatively few harms reported were minor and transient, with event rates usually comparable to harms in the control groups. Few studies reported cost-effectiveness analyses, and only for PGHD interventions for hypertension, coronary artery disease, and chronic obstructive pulmonary disease; the findings were variable across different chronic conditions and devices. Patient adherence to PGHD interventions was highly variable across studies, but patient acceptance/satisfaction and usability was generally fair to good. However, device engineers independently evaluated consumer wearable and handheld BP monitors and considered the user experience to be poor, while their assessment of smartphone-based electrocardiogram monitors found the user experience to be good. Student volunteers involved in device usability testing of the Weight Watchers Online app found it well-designed and relatively easy to use. Implications. Multiple randomized controlled trials (RCTs) have evaluated some PGHD technologies (e.g., pedometers, scales, BP monitors), particularly for obesity and hypertension, but health outcomes were generally underreported. We found evidence suggesting a possible positive effect of PGHD interventions on health outcomes for four chronic conditions. Lack of reporting of health outcomes and insufficient statistical power to assess these outcomes were the main reasons for “unclear” ratings. The majority of studies on PGHD technologies still focus on non-health-related outcomes. Future RCTs should focus on measurement of health outcomes. Furthermore, future RCTs should be designed to isolate the effect of the PGHD intervention from other components in a multicomponent intervention.

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