Sleep Architecture and Blood Pressure.

Different stages of sleep are associated with significant variability in cardiovascular function, which is mediated by marked changes in balance between 2 components of the autonomic system: parasympathetic and sympathetic. Autonomic control of circulation is essential in ensuring an adequate blood flow to vital organs through constant adjustments of arterial blood pressure, heart rate, and redistribution of blood flow. Fluctuations in components of the autonomic nervous system synchronize with electroencephalographic activity during arousal or different stages of sleep. As a result, these can lead to several cardiovascular consequences in those who have underlying heart disease or sleep-disordered breathing.