Respiratory Cycle-Dependent Atrial Trachycardia; its Unique Characteristics and Relation with Autonomic Nerve System.

Respiration influences the sinus heart rate, however, little is still known about the tachyarrhythmias related to respiration. Atrial tachycardia (AT) rarely emerges during inspiration and it also ceases during expiration. This type of AT is thus called respiratory cycle-dependent atrial tachycardia (RCAT), and it demonstrates a centrifugal activation pattern. Based on these peculiar P wave morphologies, the foci converged either around the right superior pulmonary vein (RSPV) or inside the superior vena cava where the anterior right ganglionated plexi (ARGP) is considered to be located. The mechanism of such AT is therefore thought to be related to the activity of the autonomic system.