Eur Heart J Digit Health. 2026 Jul 2;7(7):ztag108. doi: 10.1093/ehjdh/ztag108. eCollection 2026 Aug.

ABSTRACT

AIMS: Continuous positive airway pressure (CPAP) telemonitoring provides daily respiratory metrics, including Cheyne-Stokes breathing percentage (CSB%), which may reflect ventilatory-circulatory instability. However, inter-individual variability limits the clinical applicability of fixed thresholds. We developed a time-structured detection architecture using CPAP telemonitoring time-series data and evaluated its ability to identify temporal patterns preceding cardiovascular and cerebrovascular events.

METHODS AND RESULTS: In this retrospective observational study, 1265 patients with obstructive sleep apnoea undergoing CPAP telemonitoring were analysed. Daily CSB% values were smoothed using a 3-day moving average and evaluated relative to individualized dynamic baselines. The detection framework consisted of two complementary components: identification of sustained deviation from baseline and detection of abrupt pre-event surges. Central apnoea predominance, assessed using the central apnoea index, was incorporated as a hierarchical escalation layer. Among 25 adjudicated cardiovascular and cerebrovascular events in 20 patients (heart failure 11, atrial fibrillation 7, cerebrovascular accident 7), the architecture detected 23 events (92.0%) within the predefined D-28 window. Median lead time was 12.0 days (IQR 2.8-24.0). False-positive alerts were concentrated within a subset of individuals. Hierarchical filtering reduced alerts by 94.9% relative to the baseline signal layer while preserving event enrichment. Distinct temporal phenotypes, including trajectory-dominant and spike-dominant patterns, were observed across disease categories, consistent with disease-specific pre-event dynamics.

CONCLUSION: CPAP-derived CSB% may function as a time-structured digital biomarker reflecting evolving ventilatory-circulatory instability. A trajectory-based detection architecture may enable early identification of cardiovascular instability while maintaining operational feasibility in large-scale telemonitoring environments.

PMID:42602546 | PMC:PMC13475116 | DOI:10.1093/ehjdh/ztag108