A SIMPLE ATRIAL FIBRILLATORY WAVE RECONSTRUCTION METHOD FOR FREQUENCY ANALYSIS OF ATRIAL FIBRILLATION USING SINGLELEAD ECG

摘要

A cosine-function-based approximation method isproposed to reconstruct atrial fibrillatory wave in QRSTintervals for estimating dominant frequency of atrialfibrillation (AF) using single-lead ECG. It is hypothesizedthat atrial fibrillatory waves in two adjacent QRSTintervals can be approached by a cosine function anddirect component. As harmonics of dominant frequencyare neglected, the determination of harmonics’ numberand Tikhonov regularization are avoided compared withprevious methods. Initially, we build a learning data setcomposed of at most 3 TQ intervals neighboring to thetwo QRST intervals. Next, the optimum frequency ofcosine is determined in an enumeration way using thelearning data set, and the corresponding amplitude, phase,and direct component are estimated in a least squaremethod. Finally, the atrial fibrillatory waves in the twoadjacent QRST intervals are calculated based on thecosine function and direct component. This method issimple and convenient, and the atrial fibrillatory waves inectopic QRST intervals can also be easily estimated.Through evaluation with artificial and clinical AF ECG,we proved that frequency analysis of atrial fibrillationbased on this method can obtain a dominant frequencyprofile with less standard deviation than that based onABS method.