Fully Textile, PEDOT:PSS Based Electrodes for Wearable ECG Monitoring Systems.

GOAL: To evaluate a novel kind of textile electrodes based on woven fabrics treated with PEDOT: PSS, through an easy fabrication process, testing these electrodes for biopotential recordings. METHODS: Fabrication is based on raw fabric soaking in PEDOT: PSS using a second dopant, squeezing and annealing. The electrodes have been tested on human volunteers, in terms of both skin contact impedance and quality of the ECG signals recorded at rest and during physical activity (power spectral density, baseline wandering, QRS detectability, and broadband noise). RESULTS: The electrodes are able to operate in both wet and dry conditions. Dry electrodes are more prone to noise artifacts, especially during physical exercise and mainly due to the unstable contact between the electrode and the skin. Wet (saline) electrodes present a stable and reproducible behavior, which is comparable or better than that of traditional disposable gelled Ag/AgCl electrodes. CONCLUSION: The achieved results reveal the capability of this kind of electrodes to work without the electrolyte, providing a valuable interface with the skin, due to mixed electronic and ionic conductivity of PEDOT: PSS. These electrodes can be effectively used for acquiring ECG signals. SIGNIFICANCE: Textile electrodes based on PEDOT: PSS represent an important milestone in wearable monitoring, as they present an easy and reproducible fabrication process, very good performance in wet and dry (at rest) conditions and a superior level of comfort with respect to textile electrodes proposed so far. This paves the way to their integration into smart garments.

Evaluation of novel textile electrodes for ECG signals monitoring based on PEDOT:PSS-treated woven fabrics.

Despite surface electrodes technology for biopotential recording is well established, different researches are aimed at overcoming the limitations exhibited by the available solutions. In this paper, a proposal for the low-cost development of textile electrodes based on woven fabrics treated with polymer poly-3,4-ethylenedioxythiophene doped with poly(styrene sulfonate) ( PEDOT: PSS), is presented. Compared to other approaches, the proposed one can be exploited on any finished fabric. An accurate analysis of the electrodes performance, based on impedance measurements and signal processing techniques, both in wet and dry conditions, reveals the virtues and vices of the proposed solution, when used for electrocardiogram recording. In particular, the potentialities of these electrodes clearly emerge, in terms of ability to work without any electrolyte, providing a valuable interface between the skin and the electrode, in some cases achieving better performance than commercial disposable electrodes.

An advanced algorithm for fetal heart rate estimation from non-invasive low electrode density recordings.

Non-invasive fetal electrocardiography is still an open research issue. The recent publication of an annotated dataset on Physionet providing four-channel non-invasive abdominal ECG traces promoted an international challenge on the topic. Starting from that dataset, an algorithm for the identification of the fetal QRS complexes from a reduced number of electrodes and without any a priori information about the electrode positioning has been developed, entering into the top ten best-performing open-source algorithms presented at the challenge.In this paper, an improved version of that algorithm is presented and evaluated exploiting the same challenge metrics. It is mainly based on the subtraction of the maternal QRS complexes in every lead, obtained by synchronized averaging of morphologically similar complexes, the filtering of the maternal P and T waves and the enhancement of the fetal QRS through independent component analysis (ICA) applied on the processed signals before a final fetal QRS detection stage. The RR time series of both the mother and the fetus are analyzed to enhance pseudoperiodicity with the aim of correcting wrong annotations. The algorithm has been designed and extensively evaluated on the open dataset A (N = 75), and finally evaluated on datasets B (N = 100) and C (N = 272) to have the mean scores over data not used during the algorithm development. Compared to the results achieved by the previous version of the algorithm, the current version would mark the 5th and 4th position in the final ranking related to the events 1 and 2, reserved to the open-source challenge entries, taking into account both official and unofficial entrants. On dataset A, the algorithm achieves 0.982 median sensitivity and 0.976 median positive predictivity.

Telemedicine applied to kinesiotherapy for hand dysfunction in patients with systemic sclerosis and rheumatoid arthritis: recovery of movement and telemonitoring technology.

OBJECTIVE: To describe a feasibility study focused on a telemonitoring approach to self-managed kinesiotherapy sessions for the rehabilitation of hand function in patients with systemic sclerosis (SSc) and rheumatoid arthritis (RA). METHODS: Ten patients with SSc and 10 with RA were enrolled in a 3-month controlled trial (approval no. 9751/2012 - Italian Department of Health) to perform a home kinesiotherapy protocol, consisting of strengthening and mobility exercises, using a newly developed telemedicine system (a portable device and the related telemonitoring infrastructure). A further 10 patients with SSc and 10 with RA were enrolled as controls to perform a similar home kinesiotherapy protocol with the aid of common daily-life objects. Both groups were evaluated at baseline and at followup, after 6 and 12 weeks. The primary outcome of the trial was hand function measured by Dreiser's index (Functional Index for Hand OA, FIHOA), Health Assessment Questionnaire (HAQ), and the Hand Mobility in Scleroderma (HAMIS) test (only for SSc). RESULTS: Patients with SSc showed an improvement of FIHOA in both arms (p < 0.01) but the HAQ (p = 0.016) and the HAMIS test (right hand p = 0.016, left hand p = 0.075) improved significantly only in the experimental arm. Patients with RA showed a statistically significant improvement of FIHOA (p = 0.013) and HAQ (p = 0.015) in the experimental arm, while patients in the control arm did not significantly improve. However, no statistically significant differences in outcome measures between treatment methods were observed. Withdrawals were higher in control arms (SSc 20%; RA 30%) than in experimental arms (SSc 10%; RA 10%). CONCLUSION: Telemonitoring of self-administered kinesiotherapy programs is a promising approach to the rehabilitation of hand functions in patients with rheumatic disease.

A Device for Local or Remote Monitoring of Hand Rehabilitation Sessions for Rheumatic Patients.

Current clinical practice suggests that recovering the hand functionality lost or reduced by injuries, interventions and chronic diseases requires, beyond pharmacological treatments, a kinesiotherapic intervention. This form of rehabilitation consists of physical exercises adapted to the specific pathology. Its effectiveness is strongly dependent on the patient's adhesion to such a program. In this paper we present a novel device with remote monitoring capabilities expressly conceived for the needs of rheumatic patients. It comprises several sensorized tools and can be used either in an outpatient clinic for hand functional evaluation, connected to a PC, or afforded to the patient for home kinesiotherapic sessions. In the latter case, the device guides the patient in the rehabilitation session, transmitting the relevant statistics about his performance to a TCP/IP server exploiting a GSM/GPRS connection for deferred analysis. An approved clinical trial has been set up in Italy, involving 10 patients with Rheumatoid Arthritis and 10 with Systemic Sclerosis, enrolled for 12 weeks in a home rehabilitation program with the proposed device. Their evaluation has been performed with traditional methods but also with the proposed device. Subjective (hand algofunctional Dreiser's index) and objective (ROM, strength, dexterity) parameters showed a sustained improvement throughout the follow-up. The obtained results proved that the device is an effective and safe tool for assessing hand disability and monitoring kinesiotherapy exercise, portending the potential exploitability of such a methodology in clinical practice.