[Interaction between heart and brain in sudden cardiac death].

The heart and brain are constantly interacting under normal physiological conditions. This interaction is under the control of the autonomic nervous system with parasympathetic and sympathetic nerve fibers including the participating brain structures. Pathological conditions, such as epilepsy and ischemic cerebral stroke influence heart function, especially the frequency and may result in severe arrhythmia. An asymmetric influence of the left and right brain hemispheres on the heart rate is still under debate. Conversely, the influence of the heart in cases of acute cardiac arrest on brain function is equally relevant and a common clinical problem after resuscitation. We review the damaging cascade of global cerebral hypoxia and the value of different diagnostic procedures as well as the ethical problem of the point in time of termination of consciousness and the instruments for estimating the prognosis.