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

Abstract

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.

Figure 1.. Simultaneous Recordings of the Body Surface Electrocardiogram and Respiration Monitor. Respiratory Cycle-Dependent Atrial Tachycardia was Characterized by Atrial Ectopic Bursts which Emerged After Starting Inspiration and then Ceased During Expiration. The Asterisks in the Electrocardiograms Indicate Sinus Beats

Figure 2.. Posterior View of the Dissected heart. B: The Same View of the 3-Dimensional Cardiac Computed Tomography. The Figure of Dissected Heart Shows the Positional Relationship of the Right Superior Pulmonary Vein (RSPV), Superior Vena Cava (SVC), and Pericardial Reflection (PR). The Reflection of the Pericardium at the Postcaval Recess, Right Pulmonary Venous Recess, and Pericardial Oblique Sinus (POS) Anchors the Heart to the Mediastinum. C: The Contrast Radiography of the Left atrium at Deep Expiration D: The Same at Deep Inspiration. The Movement Length of Lower Side in this Figure During the Respiratory Cycle is Longer than the Upper Side where is Anchored to the Mediastinum. For Details, See Text