Arousals are spontaneous activations of the central nervous system (CNS) that cause a reaction in the autonomic nervous system (ANS). We investigated transfer entropy (TE) between CNS and ANS to characterize cardiocerebral coupling in patients with cardiovascular diseases (CVDs) and healthy subjects. 2,154 recordings from the Sleep Heart Healthy Study were investigated to find differences between both groups. CNS activity was measured by EEG band power parameters, while activity in the ANS was measured by various heart rate and QT interval variability parameters. To determinate the effect ρ of arousals, TE was calculated before and after an arousal. Information transfer from the CNS to parasympathetic dominated parameters was stronger influenced due to arousal (ρ = 1.126) compared to information transfer from CNS to sympathetic dominated parameters (ρ = 1.118). Our results indicate, that arousals lead to an activation of the parasympathetic nervous system but also an increase in the sympathetic response is necessary to return to homeostasis. The increase in information transfer due to an arousal was significantly lower (p < 0.05) in patients with CVD compared to healthy subjects, suggesting that CVD
inhibits the cardio-cerebral regulatory system. Our finding may contribute to understand the pathophysiological effects of CVD beyond the autonomic regulatory function.