Atrial fibrillation and waveform characterization

The surface electrocardiogram (ECG) is a convenient, cost effective, and noninvasive tool for the study of atrial fibrillation (AF). It can be used to examine the hypothesized mechanisms of AF as well as to quantify and assess the effect of electrophysiological remodeling and the effectiveness of treatment on different types of AF. Time domain methods can be used to characterize the signal in the surface ECG. The authors described observations that can be obtained directly from the signal, such as the general characteristics of AF in the surface ECG and the ventricular response to AF. A discussion on commonly used methods to characterize atrial activity is also presented. These methods include cancellation techniques, vector analysis, and autocorrelation. Observations show that combining time and frequency domain methods provides a more thorough understanding of the characteristics of the atrial activity in the surface ECG. Whether the study of atrial activity in the surface ECG can be used to distinctively distinguish between different mechanisms of AF is not yet known, but further investigation can improve our understanding of these mechanisms and help with the management of this common arrhythmia