Background and Aims:

Although it is well known that ischemic stroke may cause cardiovascular autonomic dysfunction, most studies focus on patients with anterior circulation stroke. In patients with posterior circulation ischemic stroke (PCIS), cardiovascular autonomic modulation has only been rarely studied. Therefore, we aimed to assess cardiovascular autonomic modulation in PCIS patients.

Methods:

In 57 patients with PCIS (12 occipital lobe, 14 thalamic, 11 cerebellar, 20 brainstem strokes) and 30 age- and gender-matched controls, we recorded RR-intervals (RRI), systolic, diastolic blood pressures (BPsys, BPdia), and respiration (RESP) at supine rest, within one week after stroke-onset. We calculated parameters reflecting total cardiac autonomic modulation [RRI-standard-deviation (RRI-SD), RRI-total-powers], mainly or exclusively sympathetic [RRI-low-frequency-powers (RRI-LF-powers) and BPsys-LF-powers] and parasympathetic cardiovascular modulation [Root-Mean-Square-of-Successive-RRI-Differences (RMSSD), RRI-high-frequency-powers (RRI-HF-powers)], sympathetic-parasympathetic balance (RRI-LF/HF-ratios), and baroreflex-sensitivity (BRS). Values were compared with one-way ANOVA or Kruskal-Wallis-Test, with post-hoc analyses. Significance was assumed for p<0.05.

Results:

In the patients of all PCIS- subgroups, values of RRI, RRI-SD, RMSSD, RRI-HF-powers, and BRS were significantly lower, while BPsys-LF-powers were higher than in the controls. In patients with ischemia in the occipital lobe, RRI-LF/HF-ratios were significant higher than in controls. Autonomic parameters did not differ between PCIS-subgroups.

Conclusions:

Within one week after PCIS-onset, patients have reduced parasympathetic and increased sympathetic cardiovascular modulation with diminished BRS. These findings are similar to our previous findings in patients after acute ischemic stroke in the middle cerebral artery territory (Hilz et al. 2011). The shift towards sympathetic predominance seems to be more pronounced in patients with occipital lobe lesions.

Abstract Body

Psychological stress may have negative effects on organ function and psychological well-being. Hans Selye considered “stress” as a ”non-specific response of the body to any demand for change“. Selye distinguished acute stress responses from the “General Adaptation Syndrome”, i.e. the responses to long-lasting stressors, with an initial alarm phase attempting to maintain homeostatic balance, a “resistance phase” during which coping strategies are activated, and the exhaustion phase when coping mechanisms fail and the person is at risk of disease. The acute stress response described by Walter Cannon as Fight-or-Flight-Response consists of acute sympathetic activation with noradrenaline and adrenaline release and responses preparing the individual for fighting or fleeing. Acute threats trigger central autonomic responses, particularly in the amygdalae and hypothalamus which activates the pituitary gland that secretes ACTH. Subsequent cortisol and adrenaline release contribute to increases in energy levels, blood glucose, lipolysis, heart rate, blood pressure, respiration, myocardial and pulmonary perfusion, pupillary diameter, muscle perfusion, and sweat output but a decrease in skin perfusion.

Acute stress may trigger syncope, arrhythmias, coronary artery constriction, Takotsubo syndrome, or sudden cardiac death. Complications of acute or chronic stress are legion and include metabolic syndrome, diabetes mellitus, arterial hypertension, arterial occlusive disease, kidney failure, stroke, myocardial infarction, chronic pain, irritable bowel syndrome, sexual dysfunction, cancer, depression, fatigue, burn-out syndrome, pseudo-dementia, cognitive dysfunction, etc. Options to reduce daily-life stressors include approaches that reduce sympathetic and increase parasympathetic activity, such as physical exercise, breathing techniques, Yoga, Tai-Chi, meditation, prayer, music, progressive muscle relaxation, or autogenic training.

Abstract Body

Psychological stress may have negative effects on organ function and psychological well-being. Hans Selye considered “stress” as a ”non-specific response of the body to any demand for change“. Selye distinguished acute stress responses from the “General Adaptation Syndrome”, i.e. the responses to long-lasting stressors, with an initial alarm phase attempting to maintain homeostatic balance, a “resistance phase” during which coping strategies are activated, and the exhaustion phase when coping mechanisms fail and the person is at risk of disease. The acute stress response described by Walter Cannon as Fight-or-Flight-Response consists of acute sympathetic activation with noradrenaline and adrenaline release and responses preparing the individual for fighting or fleeing. Acute threats trigger central autonomic responses, particularly in the amygdalae and hypothalamus which activates the pituitary gland that secretes ACTH. Subsequent cortisol and adrenaline release contribute to increases in energy levels, blood glucose, lipolysis, heart rate, blood pressure, respiration, myocardial and pulmonary perfusion, pupillary diameter, muscle perfusion, and sweat output but a decrease in skin perfusion.

Acute stress may trigger syncope, arrhythmias, coronary artery constriction, Takotsubo syndrome, or sudden cardiac death. Complications of acute or chronic stress are legion and include metabolic syndrome, diabetes mellitus, arterial hypertension, arterial occlusive disease, kidney failure, stroke, myocardial infarction, chronic pain, irritable bowel syndrome, sexual dysfunction, cancer, depression, fatigue, burn-out syndrome, pseudo-dementia, cognitive dysfunction, etc. Options to reduce daily-life stressors include approaches that reduce sympathetic and increase parasympathetic activity, such as physical exercise, breathing techniques, Yoga, Tai-Chi, meditation, prayer, music, progressive muscle relaxation, or autogenic training.