Fetal heart rate extraction from maternal abdominal ecg recordings

Abstract

System () for extracting a fetal heart rate from at least one maternal signal using a computer processor (). The system includes sensors (-) attached to a patient to receive abdominal ECG signals and a recorder and digitizer () to record and digitize each at least one maternal signal in a maternal signal buffer (A-D). The system further includes a peak detector () to identify candidate peaks in the maternal signal buffer. The signal stacker () of the system stacks the divides at least one maternal signal buffer into a plurality of snippets, each snippet including one candidate peak and a spatial filter () to identify and attenuate a maternal QRS signal in the plurality of snippets of the maternal signal buffer, the spatial filter including at least one of principal component analysis and orthogonal projection, to produce a raw fetal ECG signal which is stored in a raw fetal ECG buffer. The system further includes a fetal QRS identifier () for identifying peaks in the raw fetal ECG buffer by at least one of principal component analysis and a peak-detector followed by rule based fQRS extraction and a merger () to calculate and merge the fetal heart rate from the identified peaks.