Autonomic Nervous System and Atrial Arrhythmias. Atrial tachyarrhythmias are the most common arrhythmias in the general population. The abundant experimental evidence suggests that the autonomic nervous system plays an important role in the occurrence of atrial arrhythmias. However, complex interactions of the autonomic nervous system with the arrhythmogenic substrate make it difficult to correlate human arrhythmias with the laboratory data. Development of new methods to explore the subtle modulation of the autonomic nervous system may have implications for understanding the arrhythmogenic mechanism and providing an effective therapy.