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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.

Associations between autonomic nervous system health and cognitive performance have been described in different populations. Autonomic disturbances are a common phenomenon in patients post stroke. Little is known about the relationship between post stroke disturbances of the autonomic nervous system and the commonly occurring disturbances of cognitive functions revealed by victims of stroke. To assess the association between heart rate variability (HRV) and cognitive performance among patients post ischemic stroke and healthy age-matched controls, 13 patients post first-ever ischemic stroke aged 40-80 years and 15 age-matched healthy controls were evaluated. HRV was monitored during sustained handgrip, while breathing at a rate of six breaths per minute, while performing the serial-3 subtraction task sitting at rest, and while cycling. Patients post stroke had greater error rate in the serial-3 subtraction task, and lower HRV (both at rest and during task performance) relative to healthy controls (at rest 26 ms [10-53] vs. 43 ms [29-88]). The HRV of stroke patients showed less sensitivity to changes in testing conditions, and also failed to show the correlation with cognitive performance exhibited by the healthy subjects. Stroke patients experience autonomic nervous system dysfunction in parallel to their motor and cognitive impairments. Too often only the latter receive appropriate treatment consideration in the rehabilitation setting. The current results, and earlier research, point to the importance of focusing clinical attention to the status of the autonomic nervous system, as amelioration of its functioning is likely to enhance motor and cognitive functioning as well.

Background Autonomic nervous system (ANS) malfunction is a common sequel of stroke. The impact of lesion configuration on the expression of stroke-related ANS malfunction is largely unknown. Objective To examine the relationship between stroke location and ANS malfunction, as reflected in cardiac rhythm control. Methods 25 patients in the subacute phase post first-ever ischemic stroke were recruited for the study. Heart rate monitor (RS800CX) was used to record RR intervals analyzed as heart rate variability (HRV) parameters. Lesion data derived from follow-up CT scans of the brain was used for voxel-based lesion symptom mapping (VLSM) analysis (MEDx software, Medical Numerics) to identify voxels of the normalized brain where damage exerts a significant impact on the HRV scores. Results and conclusion ANS control of the cardiac rhythm, as expressed in the HRV, was affected by damage to a large array of cortical and subcortical structures in the right hemisphere. In the left hemisphere only damage confined to a small set of subcortical structures was shown to exert a significant impact on the recorded HRV measures. In addition, VLSM analysis disclosed a different pattern of cerebral control over two widely used standard time-dependent measures of the HRV – SDNN and RMSSD, with the former being sensitive to damage in a much larger array of structures in both hemispheres.

Aim: To describe the response of the cardiac autonomic nervous system to static and dynamic muscle contractions in post ischemic stroke patients 2 and 7 weeks post event, compared with the response of age- and gender-matched healthy controls. Methods: Participants: 12 patients post first stroke at the subacute phase and 12 healthy age-matched controls. Tools: the Polar Advanced Heart Rate Monitor (RS800CX) was used to record inter bit intervals at rest and during grip and cycling. Results: Patients post stroke, both at 2 and 7 weeks post onset time, had higher heart rate and lower heart rate variability (HRV) values at rest compared to controls. A significant reduction in HRV values was noted among healthy controls during static and dynamic muscle contractions compared to baseline. In contrast, stroke patients 2 weeks after onset did not show a cardiac reaction to static contractions. At 7 weeks post onset examination, the stroke patients showed a significant reduction in HRV both during static and dynamic contractions compared to the rest state. Conclusion: Patients post stroke in the subacute phase have alterations in cardiac rhythm regulation both at rest and during muscle effort. The extent of the cardiac autonomic response to muscle contraction is associated with contraction type and time post event. Simple measurement of HRV in different conditions enables monitoring of recovery of autonomic nervous system cardiac control.

Objective The objective of this study is to assess the autonomic nerve heart rate regulation system at rest and its immediate response to paced breathing among patients with complex regional pain syndrome (CRPS) as compared with age-matched healthy controls. Design Quasiexperimental. Setting Outpatient clinic. Subjects Ten patients with CRPS and 10 age- and sex-matched controls. Methods Participants underwent Holter ECG (NorthEast Monitoring, Inc., Maynard, MA, USA) recording during rest and biofeedback-paced breathing session. Heart rate variability (HRV), time, and frequency measures were assessed. Results HRV and time domain values were significantly lower at rest among patients with CRPS as compared with controls. A significant association was noted between pain rank and HRV frequency measures at rest and during paced breathing; although both groups reduced breathing rate significantly during paced breathing, HRV time domain parameters increased only among the control group. Conclusions The increased heart rate and decreased HRV at rest in patients with CRPS suggest a general autonomic imbalance. The inability of the patients to increase HRV time domain values during paced breathing may suggest that these patients have sustained stress response with minimal changeability in response to slow-paced breathing stimuli.