The Progression of Heart Rate Variability Parameters Throughout Cardiac Rehabilitation

To optimize exercise management in cardiac patients following a cardiac rehabilitation (CR) program, it is important to study short-term changes of parameters, representative for exercise capacity. We hypothesize that a detailed study of these parameters could provide more insight into the actual improvement of the patients. Therefore, the progression of heart rate variability (HRV) parameters during short-term intervals throughout CR was investigated in this study.Electrocardiographic (ECG) signals, recorded with a wearable device in 129 patients following a CR program, were analyzed. Patients participated in a follow up protocol. Analyses on the normalized power in the low frequency band (LFn) and the root mean square of successive differences (RMSSD) were performed for patients on and off drug therapy.Although no significant differences were found, treating CR patients with ACE-inhibition or beta blockers (BB) tended to have an influence on the HRV parameters. The progression of the HRV parameters throughout CR was mostly characterized by a non-monotonic trend. These insights elucidate the changes occurring in the regulatory mechanisms. Moreover, findings of this work give new valuable insights for the close monitoring of disease progression during CR in future applications.