Reconstruction of atrial signals derived from the 12-lead ECG using atrial signal extraction techniques

Several techniques are available for the extraction of the atrial signal from the ECG. Two of these techniques, independent component analysis (ICA) and principal component analysis (PCA), derive global atrial signals which cannot be directly compared with the atrial signals in specific leads. An algorithm for projecting into lead V1 the global atrial signals of these techniques was developed, allowing direct comparisons with the atrial activity in V1 and the atrial signal extracted by spatiotemporal QRST cancellation (STC) which derives the atrial signal directly from the ECG lead. The reconstructed atrial signals were divided into sections corresponding to ventricular activity and inactivity in lead V1 and compared against atrial activity in lead V1 in terms of amplitude and waveform shape.