Enhanced Spectral Method for T–Wave Alternans analysis

The T–wave alternans or ventricular alternans have been closely linked to electrical instability in the heart. Recent studies have demonstrated that T–wave alternans occurence is related with ventricular arrhythmias. So, T–wave alternans detection may help in the diagnostic of heart diseases and sudden cardiac death. TWA consist of a beat to beat alternation of the ST–T complex, and this alternation can be in order of μV. The noise is a critical factor to be considered as it can mask the T–wave alternans when its magnitude is close to the alternan wave. Therefore, T–wave alternans detection techniques are very dependent on the relationship between noise and alternance power. Among the T–wave alternans detection methods, the spectral method is widely used. In this work, a modified version of the spectral method algorithm is presented. The proposed method increases the alternance significance with regard to the noise in the spectral domain. Experimental study, carried out in this work, shows that this new approach yields better performance in a noisy environment.