Estimation and removal of power line interference in the electrocardiogram: a comparison of digital approaches.

Global filtering of AC interference in the digitized ECG is introduced as a new concept. Two different filters embodying a global approach are presented. One is based on a least-squares error fit, the other uses a special summation method. Both methods are compared with a local predictive filter by applying each filter to artificial signals and to real ECGs. A critical evaluation of the results is given.