The Influence of Cardiac Ablation on the Electrophysiological Characterization of Rat Isolated Atrium: Preliminary Analysis

Atrial fibrillation (AF) is the most common cardiac arrhythmia seen in the clinical practice, and treatments with antiarrhythmic drugs are of limited effectiveness. Radiofrequency catheter ablation (RFA) has been widely accepted as a strategy to treat AF. In this study, we analyzed the electrophysiological impact of different RFA strategies by varying the duration of ablation in a controlled protocol. The electrical activity of the isolated right atrium of rats, under different RFA time strategies, was acquired on the epicardium by electrical Mapping (EM), and simultaneously on the endocardium by Optical Mapping (OM). Analyses were performed in both time and frequency domain, through analysis of signal’s morphology, local activation time (LAT), conduction velocity (CV), dominant frequency (DF), and organization index (OI). The morphology of the optical and electrical signals with prolonged ablation time was altered as the ablation time increased. As observed, DF and OI decreased with the increase of the ablation time and resulted in fragmented electrograms. Through the characterization of traditional metrics applied to the electrical and optical data, it was possible to identify the important changes induced by the ablated area.