Nodal recovery, dual pathway physiology, and concealed conduction determine complex AV dynamics in human atrial tachyarrhythmias

摘要

Although there is evidence that specific nodal properties generate the AV node response under controlled stimulation protocols, the nodal determinants of complex AV patterns, observed in humans during spontaneous arrhythmic conditions, are still poorly understood.By combining data analysis and computer modeling this article aims to 7) quantify the dynamical response of the AV node at spontaneous high atrial rates in patients with different atrial flutter (AFL) episodes; 2) clarify the contribution of specific nodal properties to the observed dynamics. The elec-trophysiological features of atrial flutter make it a suitable clinical model to investigate nodal dynamics in the high-frequency range. Atrial flutter is a highly regular atrial tachycardia (26, 43), characterized by a high atrial rate >240 beats/min (14), which determines some degree of AV block.