The cardiac autonomic nervous system response to different daily demands among patients at the sub-Acute phase post ischemic stroke and healthy controls

BACKGROUND: Autonomic disturbances are a common phenomenon in patients' post-stroke, characterized by hypo function of the para-sympathetic and/or overactive sympathetic system. The impact of autonomic disturbances on physical therapy tasks during the rehabilitation period has not yet been assessed. OBJECTIVE: To describe the response of the cardiac autonomic nervous system during different tasks, among patients and age-matched healthy controls. METHODS: Nineteen patients in the subacute phase post first-ever ischemic stroke, and 16 controls. The Polar advanced heart rate monitor (RS800CX) was used to record RR intervals at rest, during paced breathing exercise, while performing different types of muscle contractions, and during single and dual task conditions. RESULTS: RR intervals and heart-rate variability (HRV) parameters were significantly lower among patients post stroke, both at rest and during most of the activities tested. Among the control group a significant autonomic adaptation was seen in the form of reduced RR intervals and HRV during muscle contraction and a significant increase in these parameters during slow breathing, no significant changes were observed among patients post stroke. CONCLUSION: Patients post-stroke experience hyper sympathetic function at rest and less adaptive cardiac autonomic control during different activities, which all may have an impact on rehabilitation outcomes.