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Wrist and arm sensing technologies for cardiac arrhythmias detection

Periodic Reporting for period 2 - WASTCArD (Wrist and arm sensing technologies for cardiac arrhythmias detection)

Période du rapport: 2017-05-01 au 2018-04-30

Title: Wrist and arm sensing technologies for cardiac arrhythmias detection in long term monitoring

Summary

Abnormal heart rhythms are a major cause of cardiovascular disease and death in Europe. Sudden cardiac death accounts for 50% of cardiac mortality in developed countries; ventricular tachycardia or ventricular fibrillation is the commonest underlying arrhythmia. In the ambulatory population, atrial fibrillation is the commonest one, and is associated with increased risk of stroke and heart failure, particularly in the aged population. If arrhythmias are detected at an early stage of heart disease, appropriate treatment can be effective, reducing disability and death. However, in the early stages of disease these may be transient, lasting only a few seconds and thus difficult to detect. Current approaches to cardiac rhythm monitoring include: a) non-invasive external recording devices; which are suitable for short term (<24 hours) recording, and b) implantable loop recorders, which are inserted subcutaneously beneath the chest wall; capable of monitoring heart rhythm for extended periods, but there is considerable expense associated with the device, hospitalisation costs and risk of infection.

This successfully completed research and innovation project through staff exchange activities, has investigated advanced technologies for non-invasive recording heart rhythm signals from the electrical activity of the heart, during long periods of time (>36 hours), using a wrist or arm wearable band device with novel electrocardiographic (ECG) sensing techniques and embedded artificial intelligence based detection processes of cardiac arrhythmias. The problem of recovering the distant heart electrogram signal from noise corrupted ECG bipolar sensing on the arm was addressed using smart digital noise filtering algorithms.

The results of the project have been published on several scientific journals and on prestigious conference proceedings. This knowledge contribution will impact by establishing a successful international and intersectoral partnership, which will attract further funding into the next translational technology stage for addressing a significant cardiovascular healthcare problem. The next generation technology will be suitable for integration into current e-Health and cardiac information systems and internet of things, and significantly impact on healthcare costs reduction by improved effectiveness on early diagnosis and early treatment of cardiac diseases.
For patient comfort and compliance, a long-term ECG recording system technique for a body surface location which is remote from the heart (eg. a wearable band on the wrist or positioned on the upper arm), it has been investigated that it is best to use dry electrodes, as in practice patients will either lose the gel or the gel-electrode interface impedance degrades. More importantly, is to avoid the use of skin adhesives for attachment onto the body; therefore, a wearable band on the wrist or upper arm, is a feasible and practical solution.

The project has addressed the related technological challenges through a multidisciplinary, multi-sectoral and international Consortium joint effort. Through the 3 years of project research and innovation actions, it has achieved the indicated 6 General Objectives presented in the Grant Agreement (GA). In Period 1 (2-year) 65% of the Project’s tasks in 13 deliverable were completed. Then by the end of Period 2 (only 1-year) 100% of project tasks and deliverable (total 20), through all the 59 Secondment actions, for a total of 72 person-month were completed. An important project task was the clinical study in Work Package 5. This was successfully completed and provided an evaluation of the possible integrated clinical knowledge.

The project has focused on the completion of the following specific objectives:
1) An advanced dry-electrode based arm-band monitoring system, which will enable continuous long-term, comfortable, non-invasive ECG recordings of cardiac patients presenting sporadic abnormalities of heart rate or rhythm, or for preventive long-term ECG screening schemes of healthy subjects, with cardiac related risks, for early detection and diagnosis of heart disease.

2) An advanced real-time signal processing technique for effective ECG denoising. Through various secondment activities in the project, an integrated technological solution in a system prototype, has enabled the clinical assessment of the combined performance of the ECG denoising technique applied to the far-field ECG signal with an adjacent pair of dry-electrode wearable system device.

The main impact observations in the Final Period are the following ones:
• An International Conference opening Keynote Speaker (invited) presentation (60 minutes) about the WASTCArD Project was presented to a large audience at the IEEE- ETCM in Ecuador, on 18/Oct.
• The WASTCArD Google website of the Project has been updated and is still live on the Internet ( https://sites.google.com/site/wastcardproject/ ).
• There were some complicated administrative procedures for some Third Country(TC) partners, eg., Venezuela, but which were successfully managed by the host organisations.
In this Period 2, INSA-Lyon managed these challenges with their hosting of one Fellow from Venezuela; nevertheless, all the administrative obstacles were managed. UniZg-FER and Ulster managed this issue well, as before in the Period before.
Technological advancement that will enable a new clinical practice by allowing continuous, long-term, non-invasive cardiac rhythm and rate monitoring (not just the heart rate) using an “adjacent” pair of ECG dry-electrodes conveniently placed, on a wearable band along the arm or wrist; thus, no surgical procedure would be required (which is the case for using an implantable “loop recorder”). The challenges of this approach lie in the difficulty of detecting an adequate cardiac electrocardiographic (ECG) signal due to the low amplitude and excessive muscle artefact in these so called “far field ECG” locations. Of particular interest in solving the ECG denoising problem in this project is the proposed software applications based on smart filtering techniques, the empirical mode decomposition (EMD), the application of an advanced cardiac ECG linear estimator method and the wavelet assessed moving-averaging method.

A functionalised advanced dry-electrode material/technique, which will enable long-term, comfortable, non-invasive ECG recordings, will be developed and assessed through this joint multidisciplinary research and innovation through staff exchange actions. Key to the successful delivery of these dry electrodes is their optimised surface structure, enabling comfortable skin contact, encouraging optimal sweat/skin contact and minimising the electrode/skin contact impedance. The overall design of the electrodes, and that of the wearable arm-band platform, will be able to minimise skin deformation potentials, which give rise to the motion artefacts which have hitherto plagued such measurements. Therefore, this impact aspect of the Project has contributed to the development of more appropriate materials for electrode/skin interface electrical performance. The innovative dry-electrode technology will then be integrated into a wearable WASTCArD prototype arm/wrist band system, as was delivered successfully by the integration and prototyping final tasks.