Estimation of arrhythmia episode using variational mode decomposition technique

Detection of life threatening arrhythmia like ventricular flutter (VFL) or ventricular tachycardia (VT) and atrial flutter (AFL) at the earlier stage may save life by defibrillation therapy. Different type of mechanism has been proposed earlier in time domain or by spectral analysis of ECG signal. In this work a frequency domain approach is proposed by spectral decomposition of ECG signal. Spectral decomposition of signal is done with the help of variational mode decomposition (VMD) technique. VMD model is used to obtain the required number of spectral mode of the test signal and their central mode of oscillation. This central frequency of decomposed signal and maximum phase change within a specified window are used to characterize ventricular tachycardia and atrial flutter and compared to normal rhythms by K-near neighbour (KNN) classification method. Accuracy of 98.6% is obtained for VT classification. The proposed method eliminates the requirement of detecting fiducial points of ECG signal as necessary in conventional classification methods.