Evaluation of the Changes in RR and QT Circadian Rhythms in Bedridden Subjects

Prolonged bed rest (BR), often related to hospitalization, chronic diseases and ageing, as well as hospitalized COVid-19 patients, induces reduced functional capacity in multiple body systems and rhythms dysregulation, possibly leading to cardiovascular deconditioning and increased arrhythmogenic risk. In this study, we analyzed 24h Holter ECGs collected from 10 healthy subjects before, during, and after a 10-day BR, aiming at assessing the decline of the circadian rhythms of RR and ventricular repolarization intervals. Our results proved that a 10-day BR induced changes in the characteristics of cardiac circadian rhythms, in terms of midline value, oscillation amplitude and acrophase, offering a first insight for the formulation of appropriate countermeasures for improving homeostasis maintenance in hospitalized patients.