Atrio-Ventricular Junction behaviour during Atrial Fibrillation

Abstract

Up to now the functioning of the Atrio-Ventricular Junction (AVJ) during Atrial Fibrillation (AF) is still not completely understood. To shed some light on the AVJ behavior during AF episodes, this study analyses the existence of a possible relationship between the occurrence of a heart beat and the power of the atrial activity (AA) preceding this heart beat in an electrocardiogram (ECG) signal. AA power is measured in the interval of the ECG between the onset of the heart beat under analysis and the ending of the previous heart beat (T-Q interval). Our analysis has shown a difference in the distributions of AA power versus cardiac cycle length (RR interval on the ECG) between healthy and pathological subjects. In particular, a negative trend between these two parameters is discovered in pathological subjects. This negative relation shows a possible coherence between power arriving at the AVJ and the triggering of the heart beat, which is in line with the assumptions made in the quantitative model for the ventricular response during AF by Cohen.