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.

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.

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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.