Comparison of Voltage Map Calculation Methods Using Non-Fractionated EGM Signals in a Persistent AF Patient

Catheter ablation targeting low voltage areas (LVA) is commonly being used to treat atrial fibrillation (AF) in patients with persistent AF. However, it is not always certain that the areas marked as low voltage (LV) are correct. This can be related to how the voltage is calculated. Therefore, this paper focuses on comparing different calculation methods, specifically, with regards to spatial distribution.Two voltage maps obtained in AF were used, removing points which did not meet the required specifications. The peaks for the remaining points, in regions of the left atrium, were then found and the voltage was calculated based on taking the peak to peak (p2p) for different beats.For around 30% of the points on the map, the voltage only changed by 0.1mV when taking one beat versus all beats. However, for some individual points, the difference was substantial, around 0.8mV, depending on the beat chosen. Additionally, the inter-method variability increased by around 0.1mV when considering all methods compared to only methods calculated using more than one point.It was found that taking the median over all p2p values in each point would be a more appropriate method for calculating the voltage. Thus, providing a technique, which could improve the accuracy of identifying LVA in an AF map.