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1.
J Vasc Access ; : 11297298241273656, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39171385

RESUMEN

Intracavitary electrocardiography (IC-ECG) is a non-invasive method for intraprocedural tip location during central venous catheterization. Over the last 20 years, the IC-ECG method has been thoroughly investigated and many studies have confirmed its wide applicability and feasibility, as well as its great accuracy and safety in different populations of patients and in different types of central venous access devices (CVADs). This retrospective study presents a two-center experience with tip location of central venous catheters using IC-ECG, by means of a new wireless portable device. Tip location was performed during 983 insertions of CVADs at bedside, using this new device. Clinical conditions with limited or no applicability of IC-ECG were excluded. The feasibility of IC-ECG, as performed using the novel device, was 92.2%. This wireless device may play an important role in central venous catheterization at bedside, since it is pocket-sized, particularly easy to use, and easy to sanify after use.

2.
Sensors (Basel) ; 24(14)2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-39065849

RESUMEN

Capacitive humidity sensors typically consist of interdigitated electrodes coated with a dielectric layer sensitive to varying relative humidity levels. Previous studies have investigated different polymeric materials that exhibit changes in conductivity in response to water vapor to design capacitive humidity sensors. However, lipid films like monoolein have not yet been integrated with humidity sensors, nor has the potential use of capacitive sensors for skin hydration measurements been fully explored. This study explores the application of monoolein-coated wireless capacitive sensors for assessing relative humidity and skin hydration, utilizing the sensitive dielectric properties of the monoolein-water system. This sensitivity hinges on the water absorption and release from the surrounding environment. Tested across various humidity levels and temperatures, these novel double functional sensors feature interdigitated electrodes covered with monoolein and show promising potential for wireless detection of skin hydration. The water uptake and rheological behavior of monoolein in response to humidity were evaluated using a quartz crystal microbalance with dissipation monitoring. The findings from these experiments suggest that the capacitance of the system is primarily influenced by the amount of water in the monoolein system, with the lyotropic or physical state of monoolein playing a secondary role. A proof-of-principle demonstration compared the sensor's performance under varying conditions to that of other commercially available skin hydration meters, affirming its effectiveness, reliability, and commercial viability.


Asunto(s)
Capacidad Eléctrica , Humedad , Piel , Tecnología Inalámbrica , Humanos , Piel/química , Tecnología Inalámbrica/instrumentación , Glicéridos/química , Glicéridos/análisis , Agua/química , Electrodos , Tecnicas de Microbalanza del Cristal de Cuarzo/métodos
3.
IEEE Sens J ; 24(6): 7308-7316, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38500510

RESUMEN

Continuous monitoring of bladder activity during normal daily activities would improve clinical diagnostics and understanding of the mechanisms underlying bladder function, or help validate how differing neuromodulation strategies affect the bladder. This work describes a urological monitor of conscious activity (UroMOCA). The UroMOCA included a pressure sensor, urine impedance-sensing electrodes, and wireless battery recharge and data transmission circuitry. Components were assembled on a circuit board and encapsulated with an epoxy/silicone molded package that allowed Pt-Ir electrode feedthrough for urine contact. Packaged UroMOCAs measured 12 × 18 × 6 mm. UroMOCAs continuously transmitted data from all onboard sensors at 10 Hz at 30 cm range, and ran for up to 44 hours between wireless recharges. After in vitro calibration, implantations were performed in 11 animals. Animals carried the device for 28 days, enabling many observations of bladder behavior during natural, conscious behavior. In vivo testing confirmed the UroMOCA did not impact bladder function after a two-week healing period. Pressure data in vivo were highly correlated to a reference catheter used during an anesthetized follow-up. Static volume sensor data were less accurate, but demonstrated reliable detection of bladder volume decreases, and distinguished between voiding and non-voiding bladder events.

4.
PeerJ Comput Sci ; 9: e1618, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37869459

RESUMEN

As a result of significant advancements in living conditions, individuals have redirected their attention towards physical exercise. Skiing, as a widely popular sport, necessitates the real-time maintenance of correct posture during movement. Therefore, we present a dynamic skiing motion capture and human posture detection model that leverages wireless device tracking. Primarily, personnel tracking is enabled through the construction of service base stations and the utilization of wireless device tracking technology. Subsequently, a human posture detection model is formulated in the form of human posture key points, employing the image information of each frame obtained via wireless devices. Finally, we introduce a spatio-temporal Transformer structure that facilitates the detection and recognition of human posture in consecutive frames. Our results demonstrate that our approach can precisely locate and track the position of skiing personnel. Compared to the latest Blip and Conformer methods, our technique yields F values that surpass them by 1.20% and 4.51%, respectively. Moreover, our model can achieve convergent model parameters and accomplish training objectives more efficiently, thus enabling posture detection and dynamic capture of skiing personnel via image and video information.

5.
Digit Health ; 9: 20552076231179014, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37312950

RESUMEN

Background: Continuous monitoring of ECG, respiratory rate, systolic and diastolic blood pressure, pulse rate, cardiac output, and cardiac index is important in patients with ST-elevation myocardial infarction (STEMI) admitted to the intensive cardiac care unit (ICCU). However, monitoring these parameters in this setting and in these patients using noninvasive, wireless devices has not been conducted so far. We aimed to assess the use of a novel noninvasive continuous monitoring device in STEMI patients admitted to the ICCU. Methods: Participants included STEMI patients that were admitted to the ICCU after primary percutaneous coronary intervention (PPCI). Patients were continuously monitored using a novel wearable chest patch monitor. Results: Fifteen patients with STEMI who underwent PPCI were included in this study. The median age was 52.8 years, the majority were males, and the median body mass index (BMI) was 25.7. Monitoring lasted for 66 ± 16 hours, and included the automatic collection and recording of all vitals, freeing the nursing staff to focus on other tasks. The user experience of nurses as reflected in filled questionnaires showed high satisfaction rates in all aspects. Conclusion: A novel noninvasive, wireless device showed high feasibility in continuously monitoring multiple crucial parameters in STEMI patients admitted to the ICCU after PPCI.

6.
BMC Anesthesiol ; 23(1): 180, 2023 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-37231335

RESUMEN

BACKGROUND: The new noninvasive Vitalstream (VS) continuous physiological monitor (Caretaker Medical LLC, Charlottesville, Virginia), allows continuous cardiac output by a low pump-inflated, finger cuff that pneumatically couples arterial pulsations via a pressure line to a pressure sensor for detection and analysis. Physiological data are communicated wirelessly to a tablet-based user interface via Bluetooth or Wi-Fi. We evaluated its performance against thermodilution cardiac output in patients undergoing cardiac surgery. METHODS: We compared the agreement between thermodilution cardiac output to that obtained by the continuous noninvasive system during cardiac surgery pre and post-cardiac bypass. Thermodilution cardiac output was performed routinely when clinically indicated by an iced saline cold injectate system. All comparisons between VS and TD/CCO data were post-processed. In order to match the VS CO readings to the averaged discrete TD bolus data, the averaged CO readings of the ten seconds of VS CO data points prior to a sequence of TD bolus injections was matched. Time alignment was based on the medical record time and the VS time-stamped data points. The accuracy against reference TD measurements was assessed via Bland-Altman analysis of the CO values and standard concordance analysis of the ΔCO values (with a 15% exclusion zone). RESULTS: Analysis of the data compared the accuracy of the matched measurement pairs of VS and TD/CCO VS absolute CO values with and without initial calibration to the discrete TD CO values, as well as the trending ability, i.e., ΔCO values of the VS physiological monitor compared to those of the reference. The results were comparable with other non-invasive as well as invasive technologies and Bland-Altman analyses showed high agreement between devices in a diverse patient population. The results are significant regarding the goal of expanding access to effective, wireless and readily implemented fluid management monitoring tools to hospital sections previously not covered because of the limitations of traditional technologies. CONCLUSION: This study demonstrated that the agreement between the VS CO and TD CO was clinically acceptable with a percent error (PE) of 34.5 to 38% with and without external calibration. The threshold for an acceptable agreement between the VS and TD was considered to be below 40% which is below the threshold recommended by others.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Humanos , Gasto Cardíaco/fisiología , Puente de Arteria Coronaria , Dedos , Arterias , Termodilución/métodos , Reproducibilidad de los Resultados
7.
Esophagus ; 20(4): 757-760, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37084162

RESUMEN

BACKGROUND: The BRAVO pH monitor system can benefit patients with ongoing GERD symptoms despite treatment and/or atypical symptoms. We aim to investigate the number and type of complications associated with the BRAVO pH capsule. METHODS: From April 2016 through February 2021, we analyzed post-marketing surveillance data from the FDA Manufacturer and User Facility Device Experience (MAUDE) database. RESULTS: During the study period, approximately 1,651 reports were identified with 2391 cases associated with a device failure, and 254 reporting a patient-related adverse event. Most device complications were due to aspiration n = 153), followed by reported pain (n = 79), injury (unspecified) (n = 63), and additional radiologic imaging (n = 44). Laceration and bleeding accounted for 29 and 19 cases. Furthermore, three patients suffered perforation. Most device failures were due to loss or failure of the Bravo capsule to bond or adhere to the esophageal mucosa as planned (n = 1269), followed by an activation or positioning failure (n = 972), premature detachment of device (n = 284), and failure of the device to record or transmit data (n = 158). CONCLUSIONS: Findings from the MAUDE database highlight the risk of aspiration, hemorrhage/bleeding, perforation, injury, and retention as potential complications of BRAVO capsule placement.


Asunto(s)
Hemorragia , Humanos , Concentración de Iones de Hidrógeno
8.
Biosensors (Basel) ; 12(11)2022 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-36354473

RESUMEN

This study presents a long-term vital signs sensing gown consisting of two components: a miniaturized monitoring device and an intelligent computation platform. Vital signs are signs that indicate the functional state of the human body. The general physical health of a person can be assessed by monitoring vital signs, which typically include blood pressure, body temperature, heart rate, and respiration rate. The miniaturized monitoring device is composed of a compact circuit which can acquire two kinds of physiological signals including bioelectrical potentials and skin surface temperature. These two signals were pre-processed in the circuit and transmitted to the intelligent computation platform for further analysis using three algorithms, which incorporate R-wave detection, ECG-derived respiration, and core body temperature estimation. After the processing, the derived vital signs would be displayed on a portable device screen, including ECG signals, heart rate (HR), respiration rate (RR), and core body temperature. An experiment for validating the performance of the intelligent computation platform was conducted in clinical practices. Thirty-one participants were recruited in the study (ten healthy participants and twenty-one clinical patients). The results showed that the relative error of HR is lower than 1.41%, RR is lower than 5.52%, and the bias of core body temperature is lower than 0.04 °C in both healthy participant and clinical patient trials. In this study, a miniaturized monitoring device and three algorithms which derive vital signs including HR, RR, and core body temperature were integrated for developing the vital signs sensing gown. The proposed sensing gown outperformed the commonly used equipment in terms of usability and price in clinical practices. Employing algorithms for estimating vital signs is a continuous and non-invasive approach, and it could be a novel and potential device for home-caring and clinical monitoring, especially during the pandemic.


Asunto(s)
Frecuencia Respiratoria , Signos Vitales , Humanos , Signos Vitales/fisiología , Algoritmos , Frecuencia Cardíaca , Electrocardiografía , Monitoreo Fisiológico/métodos
9.
Sensors (Basel) ; 22(14)2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35890917

RESUMEN

Ambient Intelligence is a vision of daily life in which intelligent devices interact with humans to make their lives easier, and the technology is invisible. Artificial Intelligence (AI) governs this smart environment and must interact with humans to best meet their needs and demands. Although voice assistants are very popular and efficient as conversational AI, under some conditions they cannot be used. Therefore, this work proposed a complementary tactile and tangible interface to converse with AI, creating new Tactile Signs. A prototype of TactCube, a wireless cube-shaped device that can interact with AI using only the tactile sense, is presented. The hypothesis is that TactCube can be manipulated with one hand and generate a sequence of numbers that can be interpreted as a new tactile language by a neural network solution. The paper describes the initial research made to define how these sequences can be generated and demonstrates how TactCube is able to do it.


Asunto(s)
Inteligencia Artificial , Percepción del Tacto , Humanos
10.
BMC Pulm Med ; 22(1): 119, 2022 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-35361176

RESUMEN

Auscultation with stethoscope has been an essential tool for diagnosing the patients with respiratory disease. Although auscultation is non-invasive, rapid, and inexpensive, it has intrinsic limitations such as inter-listener variability and subjectivity, and the examination must be performed face-to-face. Conventional stethoscope could not record the respiratory sounds, so it was impossible to share the sounds. Recent innovative digital stethoscopes have overcome the limitations and enabled clinicians to store and share the sounds for education and discussion. In particular, the recordable stethoscope made it possible to analyze breathing sounds using artificial intelligence, especially based on neural network. Deep learning-based analysis with an automatic feature extractor and convoluted neural network classifier has been applied for the accurate analysis of respiratory sounds. In addition, the current advances in battery technology, embedded processors with low power consumption, and integrated sensors make possible the development of wearable and wireless stethoscopes, which can help to examine patients living in areas of a shortage of doctors or those who need isolation. There are still challenges to overcome, such as the analysis of complex and mixed respiratory sounds and noise filtering, but continuous research and technological development will facilitate the transition to a new era of a wearable and smart stethoscope.


Asunto(s)
Ruidos Respiratorios , Estetoscopios , Inteligencia Artificial , Auscultación , Humanos , Ruidos Respiratorios/diagnóstico , Tecnología
11.
Environ Sci Technol ; 56(7): 4262-4271, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-35258949

RESUMEN

We developed an infrared (IR)-based real-time online monitoring device (US Patent No: US 10,571,448 B2) to quantify heart electrocardiogram (ECG) signals to assess the water quality based on physiological changes in fish. The device is compact, allowing us to monitor cardiac function for an extended period (from 7 to 30 days depending on the rechargeable battery capacity) without function injury and disturbance of swimming activity. The electrode samples and the biopotential amplifier and microcontroller process the cardiac-electrical signals. An infrared transceiver transmits denoised electrocardiac signals to complete the signal transmission. The infrared receiver array and biomedical acquisition signal processing system send signals to the computer. The software in the computer processes the data in real time. We quantified ECG indexes (P-wave, Q-wave, R-wave, S-wave, T-wave, PR-interval, QRS-complex, and QT-interval) of carp precisely and incessantly under the different experimental setup (CuSO4 and deltamethrin). The ECG cue responses were chemical-specific based on CuSO4 and deltamethrin exposures. This study provides an additional technology for noninvasive water quality surveillance.


Asunto(s)
Electrocardiografía , Corazón , Animales , Peces , Procesamiento de Señales Asistido por Computador , Calidad del Agua
12.
J Med Internet Res ; 22(6): e18636, 2020 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-32469323

RESUMEN

BACKGROUND: Continuous monitoring of vital signs by using wearable wireless devices may allow for timely detection of clinical deterioration in patients in general wards in comparison to detection by standard intermittent vital signs measurements. A large number of studies on many different wearable devices have been reported in recent years, but a systematic review is not yet available to date. OBJECTIVE: The aim of this study was to provide a systematic review for health care professionals regarding the current evidence about the validation, feasibility, clinical outcomes, and costs of wearable wireless devices for continuous monitoring of vital signs. METHODS: A systematic and comprehensive search was performed using PubMed/MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials from January 2009 to September 2019 for studies that evaluated wearable wireless devices for continuous monitoring of vital signs in adults. Outcomes were structured by validation, feasibility, clinical outcomes, and costs. Risk of bias was determined by using the Mixed Methods Appraisal Tool, quality assessment of diagnostic accuracy studies 2nd edition, or quality of health economic studies tool. RESULTS: In this review, 27 studies evaluating 13 different wearable wireless devices were included. These studies predominantly evaluated the validation or the feasibility outcomes of these devices. Only a few studies reported the clinical outcomes with these devices and they did not report a significantly better clinical outcome than the standard tools used for measuring vital signs. Cost outcomes were not reported in any study. The quality of the included studies was predominantly rated as low or moderate. CONCLUSIONS: Wearable wireless continuous monitoring devices are mostly still in the clinical validation and feasibility testing phases. To date, there are no high quality large well-controlled studies of wearable wireless devices available that show a significant clinical benefit or cost-effectiveness. Such studies are needed to help health care professionals and administrators in their decision making regarding implementation of these devices on a large scale in clinical practice or in-home monitoring.


Asunto(s)
Monitoreo Fisiológico/métodos , Signos Vitales/fisiología , Dispositivos Electrónicos Vestibles/tendencias , Adulto , Humanos , Estudios Longitudinales , Adulto Joven
13.
Sensors (Basel) ; 19(5)2019 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-30813516

RESUMEN

The design of wireless sensor nodes for animal tracking is a multidisciplinary activity that presents several research challenges both from a technical and a biological point of view. A monitoring device has to be designed accounting for all system requirements including the specific characteristics of animals and environment. In this work we present some aspects of the design of a wireless sensor node to track and monitor the pink iguana of the Galápagos: a recently discovered species living in remote locations at the Galápagos Islands. The few individuals of this species live in a relatively small area that lacks of any available communication infrastructure. We present and discuss the energy harvesting architecture and the related energy management logic. We also discuss the impact of packaging on the sensor performance and the consequences of the limited available energy on the GPS tracking.


Asunto(s)
Iguanas/fisiología , Tecnología Inalámbrica/instrumentación , Animales , Color , Redes de Comunicación de Computadores/instrumentación , Fenómenos Físicos , Tecnología de Sensores Remotos/instrumentación
14.
Sensors (Basel) ; 18(5)2018 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-29747374

RESUMEN

The evoked potential is a neuronal activity that originates when a stimulus is presented. To achieve its detection, various techniques of brain signal processing can be used. One of the most studied evoked potentials is the P300 brain wave, which usually appears between 300 and 500 ms after the stimulus. Currently, the detection of P300 evoked potentials is of great importance due to its unique properties that allow the development of applications such as spellers, lie detectors, and diagnosis of psychiatric disorders. The present study was developed to demonstrate the usefulness of the Stockwell transform in the process of identifying P300 evoked potentials using a low-cost electroencephalography (EEG) device with only two brain sensors. The acquisition of signals was carried out using the Emotiv EPOC® device—a wireless EEG headset. In the feature extraction, the Stockwell transform was used to obtain time-frequency information. The algorithms of linear discriminant analysis and a support vector machine were used in the classification process. The experiments were carried out with 10 participants; men with an average age of 25.3 years in good health. In general, a good performance (75⁻92%) was obtained in identifying P300 evoked potentials.


Asunto(s)
Encéfalo/fisiología , Electroencefalografía/métodos , Potenciales Relacionados con Evento P300/fisiología , Adulto , Interfaces Cerebro-Computador , Análisis Discriminante , Electrodos , Electroencefalografía/economía , Humanos , Masculino , Procesamiento de Señales Asistido por Computador , Máquina de Vectores de Soporte , Tecnología Inalámbrica , Adulto Joven
15.
Polymers (Basel) ; 9(9)2017 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-30965760

RESUMEN

In this study, an integrated flexible gas sensor was developed based on a polymer/multi-walled carbon nanotube composite film by using Bluetooth wireless communication/interface technology. Polymer/multi-walled carbon nanotube composite films were deposited over a polyimide flexible substrate for building a gas sensor array by using a drop-casting method. Sensor response was acquired through interdigitated electrodes and multi-channel sensor boards, which were linked to a Bluetooth wireless transceiver. Additionally, a double-spiral-shaped heater was built into the backside of the gas sensor array as a thermostat to protect it from the influence of ambient temperature. Multi-channel sensing responses were read on a display screen via a smartphone application (app). The advantages of this system include light weight, low cost, highly integrated sensors, wireless telecommunication, and real-time functioning. Thus, it is a promising candidate for deployment in a wearable gas-sensing system used to study air pollution.

16.
Telemed J E Health ; 22(7): 564-71, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27172448

RESUMEN

OBJECTIVE: To test the functionality and acceptability of a wireless vital sign monitor in an inpatient obstetric unit. MATERIALS AND METHODS: Pregnant women at a U.S. tertiary-care hospital wore a wireless vital sign sensor that captures heart rate, respiratory rate, and temperature. Measurements were compared with vital signs obtained by standard devices. We defined continuous capture of vital signs for 30 min with wireless data transfer to a central monitor as functional success. Acceptability was assessed per the pregnant women and nurses observing the device. Bland-Altman plots were constructed to assess agreement between the wireless sensor and standard measurements. RESULTS: Thirty of 32 enrolled pregnant women had successful monitoring; 2 cases were stopped early for non-study-related reasons. Comparing wireless sensor and standard measurements, the mean difference (limits of agreement) values at the 25th and 75th percentiles were 1.6 (±13.2) and 4.2 (±18.6) heartbeats/min, 4.2 (±6.1) and 0.7 (±5.4) respirations/min, and 0.02°C (±1.5) and 0.5°C (±1.8), respectively. Most pregnant women found the device comfortable, likeable, and useful (78%, 81%, and 97%, respectively); 80% of nurses found the monitor easy to use, and 84% would recommend it to a patient. CONCLUSIONS: We successfully obtained maternal vital signs using a simple wireless monitor with high acceptability. Well-validated monitors of this nature could significantly alleviate the human resource burden of monitoring during labor and confer greatly desired mobility to laboring pregnant women, although incorporation of blood pressure monitoring will be critical.


Asunto(s)
Satisfacción del Paciente , Tecnología de Sensores Remotos/instrumentación , Signos Vitales , Tecnología Inalámbrica/instrumentación , Adolescente , Adulto , Estudios Transversales , Femenino , Humanos , Embarazo , Tecnología de Sensores Remotos/normas , Centros de Atención Terciaria , Estados Unidos , Tecnología Inalámbrica/normas , Adulto Joven
17.
Cardiol Res ; 5(3-4): 101-107, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28348705

RESUMEN

BACKGROUND: Prevention of cardiac events during competitive sports is fundamental. New technologies with remote monitoring systems integrated into clothing could facilitate the screening of heart disease. Our aim was to evaluate the feasibility of Nuubo system during a field stress test performed by soccer players, comparing results with treadmill ergospirometry as test reference. METHODS: Nineteen male professional soccer players (19.2 ± 1.6 years) were studied. Wireless electrocardiographic monitoring during a Yo-Yo intermittent recovery test level 1 in soccer field and subsequent analysis of arrhythmias were firstly performed. Subsequently, in a period no longer than 4 weeks, each player underwent cardiopulmonary exercise testing in hospital. RESULTS: During Yo-Yo test, electrocardiogram (ECG) signal was interpretable in 16 players (84.2%). In the other three players, ECG artifacts did not allow a proper analysis. Estimation of maximum oxygen consumption was comparable between two exercise tests (VO2 max 53.3 ± 2.4 vs. 53.7 ± 3.0 mL/kg/min for Yo-Yo test and ergometry respectively; intra-class correlation coefficient 0.84 (0.63 - 0.93), P < 0.001). No arrhythmias were detected in any player during both tests. CONCLUSIONS: The use of Nuubo's technology allows an accurate single-lead electrocardiographic recording and estimation of reliable performance variables during exercise testing in field, and provides a new perspective to cardiac remote monitoring in collective sports.

18.
Healthc Technol Lett ; 1(2): 51-5, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26609377

RESUMEN

The frequency response of an implantable antenna is key to the performance of a wireless implantable sensor. If the antenna detunes significantly, there are substantial power losses resulting in loss of accuracy. One reason for detuning is because of a change in the surrounding environment of an antenna. The pulsating anatomy of the human heart constitutes such a changing environment, so detuning is expected but this has not been quantified dynamically before. Four miniature implantable antennas are presented (two different geometries) along with which are placed within the heart of living swine the dynamic reflection coefficients. These antennas are designed to operate in the short range devices frequency band (863-870 MHz) and are compatible with a deeply implanted cardiovascular pressure sensor. The measurements recorded over 27 seconds capture the effects of the beating heart on the frequency tuning of the implantable antennas. When looked at in the time domain, these effects are clearly physiological and a combination of numerical study and posthumous autopsy proves this to be the case, while retrospective simulation confirms this hypothesis. The impact of pulsating anatomy on antenna design and the need for wideband implantable antennas is highlighted.

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