Understanding and interpreting dominant frequency analysis of AF electrograms.

Dominant frequency analysis of atrial electrograms has been used to understand the pathophysiology of atrial fibrillation (AF). Although dominant frequency is an effective tool to estimate activation rate during AF, other factors besides activation rate may alter the results. Therefore, an adequate conceptual understanding of frequency domain analysis is required to properly use this technique and interpret the results. This review, while avoiding the use of formulas and equations, aims to explain fundamental theory of how signals can be decomposed into sine waves and how these sine waves relate to the activation rate detected from the electrograms. Through a series of examples and illustrations this relationship can be easily conceptualized. This will in turn allow the strengths and limitations of dominant frequency analysis to be better understood and improve its applicability to potential clinical usages.