Wearable seismocardiography for the beat-to-beat assessment of cardiac intervals during sleep

• Published in: 2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society Vol. 2014; pp. 6089 - 6091
• Main Authors: Di Rienzo, Marco, Vaini, Emanuele, Castiglioni, Paolo, Lombardi, Prospero, Parati, Gianfranco, Lombardi, Carolina, Meriggi, Paolo, Rizzo, Francesco
• Format: Conference Proceeding Journal Article
• Language: English
• Published: United States IEEE 2014
• Subjects: Adult; Electrocardiography; Estimation; Heart Function Tests - instrumentation; Heart Rate; Humans; Indexes; Myocardial Contraction; Pilot Projects; Polysomnography - instrumentation; Rail to rail inputs; Respiration; Sleep; Sleep - physiology; Space Flight; Valves
• ISSN: 1094-687X; 1557-170X
• DOI: 10.1109/EMBC.2014.6945018

Seismocardiogram (SCG) can be detected during sleep by a textile-based wearable system. This pilot study preliminarily explores the feasibility of a beat-to-beat estimation of cardiac mechanical features (RR interval, RRI, Pre-Ejection Period, PEP, Isovolumic Contraction Time, ICT, Left Ventricular Ejection Time, LVET, Isovolumic Relaxation Time, IRT) from the joint ECG and SCG assessment during sleep. The analysis of two 30-min sleep data segments from one healthy subject, indicated that 1) respiration largely influence the dynamics of most of the parameters; 2) variability of cardiac intervals is only marginally influenced by the RRI variability; 3) appreciable spectral power at frequencies <;0.1 is only observed in the RRI spectrum and not in the spectra of the other indexes; 4) IRT has a broadband variability, that is clearly different from the dynamics of the other indexes. These findings represent the very first description of the beat-to-beat variability of cardiac mechanical indexes. Further investigations on a larger population are in progress to confirm the present results.