REMOTE MONITORING OF AF RECURRENCE USING MHEALTH TECHNOLOGY (REMOTE-AF)

Background: Atrial Fibrillation (AF) detection tools have rapidly developed over the last decade alongside the evolution of mobile health (mHealth) monitoring. mHealth wearable technologies have been hypothesised to be a potential non-invasive and near continuous modality for long term detection and monitoring of atrial arrhythmias. We conducted a proof-of-concept study to evaluate changes in heart rate obtained from a consumer wearable device and compare against implanted loop recorder (ILR)-detected recurrence of AF and atrial tachycardia (AT) after AF ablation. Methods: REMOTE-AF (Remote Monitoring of AF Recurrence Using mHealth Technology; [NCT05037136][1]) was a prospectively designed sub study of the CASA-AF randomised controlled trial ([NCT04280042][2]). Participants without a permanent pacemaker had an ILR implanted at their index ablation procedure (catheter vs thoracoscopic) for longstanding persistent AF. Heart rate (HR) and step count were continuously monitored using a wrist-worn wearable device connected to a smartphone. Photoplethysmography (PPG) recorded HR data was pre-processed with noise filtration and episodes at 1 -minute intervals over 30 minutes of HR elevations (Z-score = 2) were compared to corresponding ILR data. Arrhythmias detected by ILR were validated by an independent cardiac physiologist. The AF Effect on Quality of Life (AFEQT) questionnaire was completed by participants at baseline and at the conclusion of the study. Results: Thirty-five patients were enrolled, with mean age 70.3 +/- 6.8 yrs, 12 (34%) women, and median follow-up 10 months (IQR 8-12 months). ILR analysis revealed 17 out of 35 patients (49%) had recurrence of AF/AT. Compared with ILR recurrence, wearable-derived elevations in HR ≥ 110 beats per minute had a sensitivity of 95.3%, specificity 54.1%, positive predictive value (PPV) 15.8%, negative predictive value (NPV) 99.2% and overall accuracy 57.4%. With PPG recorded HR elevation spikes (non-exercise related), the sensitivity was 87.5%, specificity 62.2%, PPV 39.2%, NPV 92.3% and overall accuracy 64.0% in the entire patient cohort. In the AF/AT recurrence only group, sensitivity was 87.6%, specificity 68.3%, PPV 53.6%, NPV 93.0% and overall accuracy 75.0%. Conclusion: Consumer wearable devices have the potential to contribute to arrhythmia detection after AF ablation, but further work is needed to improve and validate new composite detection algorithms. ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial NCT05037136 ### Funding Statement REMOTE-AF study did not receive formal funding. Smart devices and the technology used in the trial were provided by the University of Birmingham as part of funding from an Innovative Medicines Initiative European Union Horizon 2020 grant under agreement number 116074 (BigData@Heart; https://www.bigdata-heart.eu/),supported by the European Union's Horizon 2020 research and innovation programme and European Federation of Pharmaceutical Industries and Associations. The cardAIc team at the University of Birmingham/University Hospitals Birmingham NHS Foundation Trust have received funding from the National Institute for Health Research (NIHR) Birmingham Biomedical Research Centre (NIHR203326), MRC Health Data Research UK (HDRUK/CFC/01), NHS Data for R&D Subnational Secure Data Environment programme, and a British Heart Foundation Accelerator Award (AA/18/2/34218). The funders had no role in considering the study design or in the collection, analysis, interpretation of data, writing of the report, or decision to submit the article for publication. The opinions expressed in this study are those of the authors and do not represent the EU, NIHR, UK Department of Health and Social Care, or any of the listed institutions. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The trial was approved by the UK NRES ethical review board (20/NI/0089) I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes The data that support the findings of this study are available from the First Author [GA] upon reasonable request. [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT05037136&atom=%2Fmedrxiv%2Fearly%2F2023%2F05%2F10%2F2023.05.08.23289695.atom [2]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT04280042&atom=%2Fmedrxiv%2Fearly%2F2023%2F05%2F10%2F2023.05.08.23289695.atom