부산대학교 도서관

Heart rate (HR) shows oscillations with different periods as a result of the sympatho-vagal balance. The most studied ones are short-period variations and the circadian pattern. However, the existence of rhythms of longer periods has not been systematically studied. The aim of this work is to study HR long-period rhythms in a multicentric database including 336 patients in sinus rhythm, with implanted cardioverter defibrillator. We used two methodological approaches: First a rhythmometric procedure to automatically select the statistically significant rhythms present in the signal; Second, the LASSO path approach to analyze the order of activation of the rhythms, representing the importance of each rhythm. Most of the population showed a significant annual rhythm (78% day/80% night). Weekly and quarterly rhythms were also present (weekly 26% /26%; quarterly 22%/21%). Monthly rhythm was rarely present. Most present rhythm combinations were annual plus weekly (21%/21%) and annual plus quarterly (19%/18%). The order of activation given by the LASSO path was in agreement with the multicomponent rhythmometric model in the 86%/85% of the cases. The unusual long monitoring period, and the high number of patients, represent an ideal scenario to robustly assess the existence of long-term rhythms.