ThrombUS+ D2.4: Architectural design of the strap and sock wearable

D2.4 Architectural Design of the Strap and Sock Wearable J. Cesana [ComfTech], S. Annunziata [ComfTech], L.A. Moltani [ComfTech], S. Didaskalou [ATHENA], R. Jurkonis [KTU], V. Marozas [KTU], A. Lukoševičius [KTU], F. Schubert [MEDIS], S. Balling [MEDIS] Due Date: 31 December 2024 Delivery Date: 31 December 2024 Revision Date: 10 November 2025 Horizon Innovation Action | Agreement No. 101137227 HORIZON-HLTH-2023-TOOL-05-05 Co-funded by the European Union D2.4| Architectural design of the system v2.0 | 10 Nov 2025 ii ThrombUS+ Consortium ATHENA Research and Innovation Center in Information, Communication and Knowledge Technologies, Greece Eleni Kaldoudi [email protected] KTU Kaunas University of Technology Lithuania Vaidotas Marozas [email protected] VERMON Vermon SA France Mathieu Legros [email protected] FRAUNHOFER Institute for Photonic Microsystems, Fraunhofer Germany Nicolas Lange [email protected] TELEMED Telemed Ultrasound Medical Systems Lithuania Dmitry Novikov [email protected] EchoNous EchoNous Inc USA Pavlos Moustakidis [email protected] MEDIS medis Medizinische Messtechnik GmbH Germany Susann Balling [email protected] ComfTech ComfTech SLR Italy Lara Alessia Moltani [email protected] TAU Faculty of Medicine and Health Technology Tampere University, Finland Antti Vehkaoja [email protected] LMSU Lithuanian University of Health Science Lithuania Andrius Macas [email protected] GNP Papageorgiou General Hospital Greece Maria Bigaki [email protected] CSS-IRCCS Home Relief of Suffering Hospital Italy Elvira Grandone e.grand[email protected] HSV Simon Veil Hospital France Maxime Gautier [email protected] VDE Association for Electrical, Electronic & Information Technologies, Germany Thorsten Prinz thorsten[email protected] MEDEA MEDEA SRL Italy Pietro Dionisio [email protected] PHAZE Clinical Research and Pharma Consulting SA Greece Spiros Anagnostopoulos [email protected] PBY PredictBy Research and Consulting SL Spain Frans Folkvord [email protected] SciGen SciGen Technologies SA Greece Katerina Pavlidi [email protected] Disclaimer This document contains description of the ThrombUS+ project work, findings, and products. The authors of this document have taken any available measure for its content to be accurate, consistent and lawful. However, neither the project consortium as a whole nor the individual partners that implicitly or explicitly participated in the creation and publication of this document hold any sort of responsibility that might occur as a result of using its content. Views and opinions expressed are those of the author(s) only and do not necessarily reflect those of the European Union or HADEA. Neither the European Union nor the granting authority HADEA can be held responsible for them. In case you believe that this document harms in any way intellectual property held by you as a person or as a representative of an entity, please do notify us immediately. ThrombUS+ is an Innovation Action Project co-funded by the European Union, under HORIZON-HLTH-2023-TOOL05-05 “Harnessing the potential of real-time data analysis and secure Point-of-Care computing for the benefit of person-centred health and care delivery”. D2.4| Architectural design of the system v2.0 | 10 Nov 2025 iii Document Control Page Project Grant Agreement: 101137227 Acronym: ThrombUS+ Title: Wearable Continuous Point-of-Care Monitoring, Risk Estimation and Prevention for Deep Vein Thrombosis Type: Innovation Action Start: 1 January 2024 End: 30 June 2027 Programme: Horizon Europe Call Identifier: HORIZON-HLTH-2023-TOOL-05-05 Call Topic Harnessing the potential of real-time data analysis and secure Point-of-Care computing for the benefit of person-centred health and care delivery Website: http://thrombus.eu/ Deliverable # 13 No: D2.4 Deliverable Title: Architectural design of the strap and sock wearable Deliverable Type: R Classification: SEN Task: T2.4 Co-creation of architectural design [M04-M12] Task Leader: ComfTech [L.A. Moltani] Work Package: WP2. Requirements and product co-design [M01-M12] Work Package Leader: PBY [L.J. Segal] Responsible Partner: ComfTech Authors: J. Cesana [ComfTech], S. Annunziata [ComfTech], L.A. Moltani [ComfTech], S. Didaskalou [ATHENA], R. Jurkonis [KTU], V. Marozas [KTU], A. Lukoševičius [KTU], F. Schubert [MEDIS], S. Balling [MEDIS] Input from: All consortium partners Peer Reviewers: M. Legros [VERMON], A. Sakalauskas [TELEMED] Due Date: M12 – 31 December 2024 Delivery Date: 31 December 2024 Revision Date: 10 November 2025 Document Status Version: 2.0 Status: Draft Consortium reviewed WP leader endorsed Coordinator endorsed D2.4| Architectural design of the system v2.0 | 10 Nov 2025 iv Revision History Version Date Modification Contributors 0.1 30 Sep 2024 New content - Outline J. Cesana, S. Annunziata [ComfTech] 11 Oct 2024 New content - Outline J. Cesana [ComfTech] 14 Oct 2024 New content – Sec 1 J. Cesana [ComfTech] 28 Oct 2024 New content – Sec 2, 3 J. Cesana [ComfTech] 4 Nov 2024 New content – Sec 2 J. Cesana [ComfTech] 6 Nov 2024 New content – Sec 2 J. Cesana [ComfTech] 7 Nov 2024 Contents review J. Cesana, S. Annunziata [ComfTech] 0.2 11 Nov 2024 Contents review, New Content – Sec 2, 3 J. Cesana [ComfTech] 19 Nov 2024 Contents review J. Cesana [ComfTech] 22 Nov 2024 Contents review J. Cesana, S. Annunziata [ComfTech] 26 Nov 2024 Contents review J. Cesana [ComfTech] 27 Nov 2024 Comments on ultrasonic and compression components R. Jurkonis [KTU] 27 Nov 2024 Comments on ultrasonic and compression components A. Lukoševičius [KTU] 02 Dec 2024 Addition of content Chapter 2 and first Review F. Schubert, S. Balling [medis] 02 Dec 2024 Contents review L.A. Moltani [ComfTech] 03 Dec2024 Addition of content and review of Chapter 2 V. Marozas [KTU] 06 Dec 2024 Integration from Partners input J. Cesana [ComfTech] 0.3 11 Dec 2024 Review and correction of the content S. Didaskalou [ATHENA] 12 Dec 2024 Integration from Partners input J. Cesana [ComfTech] 13 Dec 2024 Review of whole text, added Executive Summary and Conclusions J. Cesana, S. Annunziata [ComfTech] 0.4 20 Dec 2024 Integrations from reviewers feedback J. Cesana [ComfTech] 1.0 23 Dec 2024 Editted for comformity and submission E. Kaldoudi [ATHENA] 2.0 10 Nov 2025 Revised based on PR1 review comments: “correct the typo in page 18 "hgjuPeriod of use" E. Kaldoudi [ATHENA] D2.4| Architectural design of the system v2.0 | 10 Nov 2025 v Contents About ThrombUS+ ...................................................................................................................................................... 1 Deliverable D2.4 Description ...................................................................................................................................... 1 Cite this Document as ................................................................................................................................................. 1 Terms and Definitions ................................................................................................................................................ 2 Executive Summary .................................................................................................................................................... 4 1. Introduction ........................................................................................................................................................ 5 1.1. Purpose of the deliverable ................................................................................................................................. 5 1.2. Context and structure of the deliverable ........................................................................................................... 5 2. ThrombUS+ System Architecture ........................................................................................................................ 6 2.1. System modules ................................................................................................................................................. 6 2.2. System submodules ........................................................................................................................................... 7 2.3. Overview of the system architecture ............................................................................................................... 11 2.3.1. Scenarios of use ...................................................................................................................................... 12 2.3.2. Data flows ............................................................................................................................................... 13 3. Architecture of the wearable .............................................................................................................................15 3.1. General Design Requirements for RUCs .......................................................................................................... 17 3.2. Wearable Ultrasound Device ........................................................................................................................... 19 3.2.1. WUSD Architecture................................................................................................................................. 19 3.2.2. Wearable Design Requirements ............................................................................................................. 20 3.3. Wearable Sensors Network ............................................................................................................................. 21 3.3.1. WSN Architecture ................................................................................................................................... 21 3.3.2. Wearable Design Requirements ............................................................................................................. 23 4. Conclusions ........................................................................................................................................................23 D2.4| Architectural design of the wearable v2.0 | 10 Nov 2025 1 About ThrombUS+ Deep vein thrombosis (DVT) is the formation of a blood clot within the deep veins, most commonly those of the lower limbs, causing obstruction of blood flow. In 50% of people with DVT, the clot eventually breaks off and travels to the lung to cause pulmonary embolism. Clinical assessment of DVT is notoriously unreliable because up to 2/3 of DVT episodes are clinically silent and patients are symptom free even when pulmonary embolism has developed. Early diagnosis of DVT is crucial and despite the progress made in ultrasound imaging and plethysmography techniques, there is a need for new methods to enable continuous monitoring DVT diagnosis at the point of care. ThrombUS+ brings together an interdisciplinary team of industrial, technology, regulatory, social science and clinical trial experts to develop a novel wearable diagnostic device for point-of-care, operator free, continuous monitoring in patients with high DVT risk. The device will combine autonomous, AI driven DVT detection based on a novel wearable ultrasound hardware, impedance plethysmography and light reflection rheography for immediate detection of blood clot formation in the lower limb. Activity and other physiological measurements will be used to provide a continuous assessment of DVT risk and support DVT prevention via serious gaming. The aggregated data will drive an intelligence decision support unit that will provide accurate monitoring and alerts. Extended reality will be used to guide experts to design exercises and patients to use the device optimally. ThrombUS+ is intended for use by postoperative patients in the ward, during long surgical operations, cancer patients or otherwise bedridden patients at home or in care units, and women during pregnancy and postpartum. ThrombUS+ will use big data sets for AI training collected in the project via 3 large scale clinical studies and will validate the outcome in the clinical setting via 1 early feasibility study and 1 multi-center clinical trial. Deliverable D2.4 Description D2.4 is a report on the overall design of the ThrombUS+ wearable system. This report is the output of Task 2.4. The aim of Task 2.4 is to define the overall architectural of the ThrombUS+ system. Envisioning the schematic configuration of the system, this report defines the correlations of different parts, considering that sensors, hardware and software must co-exist and integrate with each other to achieve the project goal. An extended summary of the report will also be available as a public document. Cite this Document as Cesana J, Annunziata S, Moltani LA, Didaskalou S, Jurkonis R, Marozas V, Lukoševičius A, Schubert F, Balling S, Architectural design of the strap and sock wearable, Deliverable 2.4, ThrombUS+ Horizon Europe Innovation Action, EC Grant Agreement No. 101137227, 31 December 2024. Revised on 10 November 2025. https://doi.org/10.5281/zenodo.17642398 D2.4| Architectural design of the system v2.0 | 10 Nov 2025 2 Terms and Definitions Abbreviation Definition AI Artificial Intelligence API Application Programming Interface CDUS Compression Duplex Ultrasound CHI Identifier for ThrombUS+ Central Hub & Intelligence Module CUS Compression Ultrasound Imaging CSW C-shell type Semirigid Wearable DoA Description of Action EAC Identifier for ThrombUS+ Electronic Actuator Controller EC European Commission EEA Ethics External Advisor EIM Identifier for ThrombUS+ Electrical Impedance Module EIP Electrical Impedance Plethysmography EU European Union GA General Assembly (when within the context of project management procedure) HADEA European Health and Digital Executive Agency IMU Inertial Measurement Unit LAM Identifier for ThrombUS+ Limb Activity Module LRM Identifier for ThrombUS+ Light Rheography Module LRR Light Reflection Rheography ML Machine Learning PPG Photoplethysmography PZT Pb (ZrTi) - short form of Lead zirconate titanate RUCs Reference Use Cases SAB Stakeholders Advisory Board TL Task Leader US Ultrasound USM Identifier for ThrombUS+ Ultrasound Monitoring Module VOP Venous Occlusion Plethysmography WAM Identifier for ThrombUS+ Wearable Actuator Module WP Work Package WPL Work Package Leader D2.4| Architectural design of the system v2.0 | 10 Nov 2025 3 Abbreviation Definition WSN Identifier for ThrombUS+ Wearable Sensors Network WTE Identifier for ThrombUS+ Wearable Tetrapolar Electrode WTC Identifier for ThrombUS+ Wearable Thigh Cuff WUSD Identifier for ThrombUS+ Wearable Ultrasound Device XGM Identifier for ThrombUS+ Extended Reality and Serious Gaming Module XR Extended Reality D2.4| Architectural design of the system v2.0 | 10 Nov 2025 4 Executive Summary The ThrombUS+ project represents a groundbreaking advancement in the early detection, monitoring, and prevention of Deep Vein Thrombosis (DVT). This initiative is centred around the development of a wearable diagnostic system that combines ultrasound imaging, impedance plethysmography, and light reflection rheography, powered by artificial intelligence for real-time decision-making and risk assessment. Deliverable D2.4 outlines the architectural design of the ThrombUS+ system. The report encompasses the conceptual design and configuration of two primary wearable modules: the Wearable Ultrasound Device (WUSD) and the Wearable Sensors Network (WSN). These modules integrate diverse technologies and sensors to facilitate point-of-care, continuous monitoring. The design emphasizes modularity to ensure adaptability, comfort, and scalability while adhering to clinical, technical, and regulatory requirements. The architectural design draws on extensive interdisciplinary collaboration, incorporating insights from 18 project partners spanning industry, academia, and healthcare. Key considerations include rigorous integration of advanced hardware and software components, alongside user-centric usability, and sustainability. Through its modular configuration, ThrombUS+ aims to support high-risk groups of patients with seamless monitoring and intervention capabilities. By enabling continuous DVT monitoring and risk estimation, the system is poised to redefine clinical workflows, enhance patient outcomes, and contribute to preventive healthcare. D2.4| Architectural design of the system v2.0 | 10 Nov 2025 11 2.3. Overview of the system architecture ThrombUS+ high level architecture is illustrated in Figure 3. This architecture is the first version of the conceptual model that defines the structure of the system as a whole and the connections between the submodules. Figure 3. High-level architecture of the ThrombUS+ system. All modules are connected to and controlled by the Central Hub & Intelligence, which autonomously detects the modules connected and assists Medical Experts in DVT screening, diagnosis, monitoring and prevention according to the Reference Use Case. CHI is a software that is installed and runs on an off-the-shelf Windowsbased platform. Connections between modules: − The EIM (red) has its own controller for communicating with CHI via Wi-Fi. − The LAM sensors (yellow) are connected by wire to the LAM Controller and this Controller is connected to the CHI via Wi-Fi. − The WAM (blue) and the USM (light blue) communicate with the CHI via a USB cable through the EAC and the Beamformer respectively. − The LRM (orange) communicates with CHI via Wi-Fi. Power supply: − The Beamformer and the EAC rely on a USB cable from the laptop on which the CHI is installed. − The LRM Sensor has an integrated rechargeable battery, − The Controller of EIM and LAM are powered by an external rechargeable battery. Data transmission: − The Beamformer and the EAC use the same USB connector used for the power supply, − The EIM, LRM and LAM use Wi-Fi, via the communication protocol that will be defined in D6.1. D2.4| Architectural design of the system v2.0 | 10 Nov 2025 12 2.3.1. Scenarios of use The intended purpose of the ThrombUS+ system is quoted below, as stated in Deliverable 2.3: “ThrombUS+ is an active wearable diagnostic device for point-of-care, continuous (intermittent) monitoring in patients with increased risk for deep vein thrombosis (DVT), that is applied to the patient’s lower limb. For this purpose, ThrombUS+ autonomously combines compression ultrasound imaging (CUS), electrical impedance plethysmography (EIP), and light reflection rheography (LRR) to assess blood clot formation and blood flow on the lower limbs. Additionally, ThrombUS+ uses inertial measurement units (IMUs) to monitor patient’s lower limb activity. Via an extended reality (XR) environment and serious gaming, patients are trained and motivated, respectively, to perform lower limb exercises for DVT prevention at the point of care. ThrombUS+ is intended for application to adult patients in the clinical environment by healthcare professionals.” Starting from this definition it is possible to identify at least two main scenarios of use, presented in Figure 4 and Figure 5, respectively: 1. Point-of-care monitoring through compression ultrasound imaging (CUS), electrical impedance plethysmography (EIP), and light reflection rheography (LRR) to assess blood clot formation and blood flow on the lower limbs. In this first scenario, the healthcare personnel apply the WUSD or the WSN wearable on the patien, depending on the type of examination they would like to perform. The CHI autonomously detects the modules connected and assists the Medical Experts during the procedure through a specific user interface. This scenario includes three sub-scenarios: online imaging, measurements, and calibration by the operator; operator-independent intermittent monitoring; offline visual analysis of collected historical data. Figure 4. Use case scenario 1: Patient monitoring at the point-of-care using compression ultrasound, electrical impedance plethysmography and light reflection rheography. 2. Guide the users to perform lower limb exercises for DVT prevention at the point of care, through the use of an extended reality environment and serious gaming, combined with inertial measurement units (IMUs) if needed. In this second scenario, the Medical Experts make the Patient wear the WSN and use the XGM software to prescribe the exercises they would like Patients to perform. The CHI, via XGM software, assists the Medical Experts during the whole session and also guides the Patient through specific user interfaces. D2.4| Architectural design of the system v2.0 | 10 Nov 2025 13 Figure 5. Use case scenario 2: Point-of-care patient guidance on performing the prescribed lower limb DVT-prevention exercises, via an extended reality. Additionally, through serious gaming patients are motivated to perform the prescribed exercises. 2.3.2. Data flows Below are briefly described the data flow related to the main use case scenarios, also divided for technology used for examination. Security will be ensured for sensitive data processing, and specific methods of protecting data will be considered and defined during WP6, as well as other detailed specifications. 1. Ultrasound examination: USM and the WAM are used to obtain compression ultrasound imaging (CUS) to assess blood clot formation and blood flow on the lower limbs (Figure 6). At the point-of-care, the Medical Expert uses the ThrombUS+ software to easily perform the US examination. The ThrombUS+ system will be able to collect ultrasound images for AI/ML models, included in the CHI software, which will process them to help the experienced physician assess the overall probability of DVT. Figure 6. Data flow during a compression ultrasound examination. The ultrasound examination cycle starts from the CHI by sending specific input to the beamformer utilizing the ultrasound monitoring software. The beamformer carries out the whole examination procedure thereafter. Initially, the beamformer sends specific input to the EAC to start the inflation cycle of the CSW and simultaneously initiates ultrasound imaging. Ultrasound imaging data are formed in the beamformer and are used as feedback for the examination progress. Upon examination completion, Electrical Actuator Controller (EAC) deflates the air bladders of the CSW and gathered data are sent back to the CHI for further processing and storage via the Ultrasound Monitoring Module software. D2.4| Architectural design of the system v2.0 | 10 Nov 2025 14 2. EIP examination: Flow description EIM and the WAM are used for electrical impedance plethysmography to assess blood clot formation and blood flow on the lower limbs (Figure 7). At the point-of-care, the Medical Expert uses the ThrombUS+ software to easily perform the EIP examination. The ThrombUS+ system will be able to collect electrical impedance data for the AI/ML models, included in the CHI software, which will process them to help the Medical Expert assess the overall probability of DVT. Figure 7. Data flow during electrical impedance plethysmography examination. The EIP examination cycle starts from the CHI, by sending specific inputs to the EAC to initiate the inflation cycle of the WTC, utilizing the Wearable Actuator Module software. When WTC achieves a desired level of pressure, EAC sends data back to CHI through the Wearable Actuator Module software, and in turn, CHI sends data to EIM controller to initiate EIP measurements, via the Electrical Impedance Module software. When measurements are completed, data are sent back to CHI for further processing and storage, and CHI send specific inputs to EAC to release pressure, both via the utilisation of the Electrical Impedance Module software. 3. LRR examination: LRM sensors are used for light reflection rheography to assess blood clot formation and blood flow on the lower limbs (Figure 8). At the point-of-care, the Medical Expert uses the ThrombUS+ software to easily perform the LRR examination. The ThrombUS+ system will be able to collect specific data for the AI/ML models, included in the CHI software, which will process them to help the Medical Expert assess the overall probability of DVT. Figure 8. Data flow during light reflection rheography examination. D2.4| Architectural design of the system v2.0 | 10 Nov 2025 15 The LRR examination cycle starts from the CHI, by sending specific input to the LRM sensor, via the utilization of the LRM software. The LRM sensor is carrying out the whole examination thereafter. Upon examination completion, the LRM sensor sends the data back to the CHI for further processing and storage, through the usage of Light Rheography Module software. 4. XR and serious games: The XGM and the LAM are used to guide the users to perform lower limb exercises for DVT prevention at the point-of-care, the Medical Expert uses the ThrombUS+ software to prescribe specific exercises to the Patient (Figure 9). While the Patient performs the exercises, the LAM detect the movements for the AI/ML models, included in the CHI software, to give feedback both to the Patient and the Medical Experts. Figure 9. Data flow during the extended reality and serious gaming module usage for patient guidance and empowerment. The XR and serious gaming interface initiates by the CHI sending specific data to the XGM software. Simultaneously, the CHI initiates the communication with limb activity monitoring sensors, via the Limb Activity Monitoring software. Streamed data from the sensors are received via the Limb Activity Module software and are sent to the XGM module through the CHI. 3. Architecture of the wearable Based on the required positioning of each wearable submodule on the limbs, a new representation of the architecture can be created to visualize the system's configuration in relation to its positioning on the patient (Figure 10) and its connections (Figure 11). Given the multiple functionalities of the ThrombUS+ system and the necessity to operate on the same areas of the limbs, the solution will involve two separate wearables that can also be worn individually. The Wearable Ultrasound Device (WUSD) includes the CSW, the EAC, and the Transducer, the Wearable Sensors Network (WSN) includes the WTC, the EAC, the WTE and EIM Controller, the LRM Sensor, and the LAM Sensors and LAM Controller. The WUSD and the WSN are detailed in Subsection 3.2. Wearable Ultrasound Device and 3.3. Wearable Sensors Network. D2.4| Architectural design of the system v2.0 | 10 Nov 2025 16 Figure 10. Schematic representation of the two identified wearable devices, along with their hardware submodules. Figure 11. Schematic representation of the architectural design of the two identified wearables, as well as their interconnection with the rest of the ThrombUS+ submodules. This modular configuration offers numerous benefits for the stakeholders: 1. Enhanced efficiency and adaptability: The Consortium will have the flexibility to utilize the system as a comprehensive, integrated solution, or to deploy its components separately. This approach enhances the potential for the exploitation plan by allowing diverse applications of the system, thereby catering to various needs and requirements. Additionally, the ability to scale each component independently ensures that the Consortium can adapt to changing demands and optimize effectively. This dual approach D2.4| Architectural design of the system v2.0 | 10 Nov 2025 17 not only broadens the range of opportunities but also enhances the overall effectiveness and efficiency of the system; 2. Reduction in maintenance and replacement costs: the modular design significantly reduces repair and replacement costs. Instead of replacing or repairing an entire system when a component malfunctions, only the affected module requires attention. This targeted approach minimizes downtime, reduces expenses, and ensures faster restoration of functionality. 3. Scalability and future-proofing: the modular design enables the system to evolve with technological advancements or changing user requirements. New features or modules can be integrated seamlessly without disrupting the overall functionality, ensuring the system remains relevant and adaptable over time. 4. Enhanced usability: using only the components relevant to the specific RUC simplifies the procedures for both the patients and the medical experts. Patients will wear a streamlined system that includes only essential components, minimizing discomfort and enhancing discretion, meanwhile, medical experts will be able to manage a complex system that autonomously adjusts to its individual active components, facilitating a more efficient interaction. 5. Enhanced accessibility: the modular configuration is advantageous for patients with wounds, mobility restrictions, or other special needs. For instance, components can be selectively omitted to accommodate specific medical conditions, ensuring that the system remains comfortable, effective, and accessible for all users. 3.1. General Design Requirements for RUCs Starting from D2.1. Patient-centric cases and requirements definition, where 7 Reference Use Cases (RUCs) have been defined to identify the prevalent DVT patient profiles, it is possible to collect information that emerged from the interviews with medical experts related to the design of the wearable components of the system. The 7 RUCs are listed below, specific description can be found in the Deliverable mentioned above: RUC #1 – Neurosurgery RUC #2 – Lower limb orthopaedic surgery RUC #3 - Cardiovascular surgery and risk RUC #4 – Pregnancy and postpartum RUC #5 – Cancer and oncological treatment RUC #6 – Obesity RUC #7 – Autoimmune diseases and genetic disorders The information for each RUCs that will guide the design choices are summarised in Table 2 below. D2.4| Architectural design of the system v2.0 | 10 Nov 2025 18 Table 2. Summarization of the Reference Use Cases and their features that guide the design of ThrombUS+ wearables. RUC #1 RUC #2 RUC #3 RUC #4 RUC #5 RUC #6 RUC #7 Suggested Design An intermittent compression stocking. Belt-type wearable for the thighs can be a good alternative to stocking. A stockingshaped design could be suitable. A stocking, strap, belt, or band. A stocking, strap, belt, or band. An intermittent compression stockings. An intermittent compression stockings. Features Modular to adapt to different stages of recovery. Prevent skin irritation. Minimally invasive, lightweight, breathable and flexible. Avoid compressing wounds. Includes antiembolism compression. Must avoid excessive pressure or irritation. Continuous compression can be uncomfortable or painful. Light, breathable, and comfortable. Comfortable for near 24/7 wear, including during sleep. Easy to use and comfortable to ensure that patients can spontaneously wear it even during sleep. Easy to use and comfortable, since patients are already weary by their medication. Leg/legs Both legs. Both legs. Both legs. 90% of cases on the left leg. Both legs. Both legs. Both legs. Desired Additional features N/A N/A N/A Saturation, pulse rate, and respiratory rate and real-time alerts, data storage at least for 24 hours. Adapt to other body parts should be considered. Adapt to other body parts should be considered. Adapt to other body parts should be considered. Monitoring Continuous during the critical postsurgery period. Scan at least every 12 hours starting from 1 hour postoperation, especially in the critical first three days. Scan every 4 hours. Continuous monitoring at home or during travel for moderate-risk cases. Continuous. Continuous. Continuous. Period of use Days. Days. Days. Long-term use. Long-term use (months, years or rest of life). Long-term use (months, years or rest of life). Long-term use (months, years or rest of life). Table 2 suggests that the most recommended type of wearable by the consulted medical experts are stockings because they are firm and do not slip away from their designated position. Also, strap, belt, or band designs can be considered. The system should be able to monitor both legs to account for the needs of most RUCs. The common features of all RUCs are the importance of ease of use and interaction with the device, and the need to ensure patient’s comfort when wearing the device, avoiding invasiveness and excessive compression. Also, for patients that require long-term use, the system should be unobtrusive. D2.4| Architectural design of the system v2.0 | 10 Nov 2025 19 Clinical Studies C1 and C2, ThrombUS+ early feasibility study and clinical trial [M29-M42], will guide the definition of which configuration of the ThrombUS+ system is more appropriate for each RUC. 3.2. Wearable Ultrasound Device This wearable component of the ThrombUS+ system is envisioned starting from WP3 “Wearable ultrasound device”, where TELEMED, VERMON, Fraunhofer IPMS and KTU are working together for an innovative solution based on ultrasound technology for DVT monitoring. Detailed characteristics of each component of the WUS can be found in the respective reports accompanying the deliverables of each component’s prototypes: D3.1 Ultrasound transducer array prototypes with composite based PZT technology D3.2 Ultrasound transducer prototypes based on MEMS D3.3 Precise, silent tissue compression actuator prototypes 3.2.1. WUSD Architecture This component of the system operates mainly on the upper part of the lower limbs to perform compression ultrasound autonomously through the use of the WAM and the USM (Figure 12). These modules will be able to recreate the manually operated examination for DVT evaluation and should address the lack of solutions for long-term continuous and/or intermittent monitoring and monitoring of DVT risk. This requires a wearable solution integrating configurable ultrasonic transducer, inflatable cuffs for venous occlusion, and other specific components for correct functioning. Figure 13 represents a more detailed structure of the WUSD (left) and its possible different positioning on the limb (right). Figure 12. The architectural design of the wearable ultrasound device (WUSD). D2.4| Architectural design of the system v2.0 | 10 Nov 2025 20 Figure 13. An intersection of a worn WUSD, indicating the position of each submodule on the leg (left). A different approach, using multiple WUSDs for ultrasound-based assessment of blood flow along the lower limb. (right). Technical and functional requirements that have an impact on the requirements of this wearable are summarized below: CSW: − has a semirigid configuration to integrate the imaging Transducer and the air bladders, the C-shell type inserts cover around the thigh and are used to house the Transducer and reinforce the wearable to apply pressure to the limb; and − includes the air bladders, positioned on the opposite side of the thigh. EAC: − includes an ultrasonic piezo disc pump to provide air pressure; − uses two pressure sensors measuring pressure in each of the bladders; and − is connected to the CHI via a USB cable. Transducer: − is mounted on-body and in contact with the skin of the patient; − its enclosure is waterproof-designed to be integrated into the CSW and removable for cleaning; and − is connected to the Beamformer via a multi-line cable. 3.2.2. Wearable Design Requirements Specific requirements for the design of the wearable components related to the WUSD are defined taking into account not only the technical and functional requirements of the submodules that it has to integrate in it, but also the wearability and comfort for final users.