Fig. 2.

(A) (Upper panel) Subtraction of QRS complex from the measured MCG signals in the lateral plane. The blue line shows the original MCG signals recorded for 6 s during AF. The red line shows the residual F waves after subtracting the QRS complex. (Lower panel) Periodograms corresponding to all 64 channels. The black rectangles are the excluded periodograms having DFs out of the biological range. The red rectangle indicates the periodogram having the highest OI among the 64 channels (DF=5.76 Hz, OI=0.51). (B) (Left panel) Intracardiac electrograms recorded at the LAA for 6 s. (Right panel) The DF and OI are 5.50 Hz and 0.45, respectively. The periodogram corresponding to the electrograms recorded at the LAA is in good agreement with that corresponding to the MCG signal in the lateral plane. AF=atrial fibrillation; DF=dominant frequency; LAA=left atrial appendage; MCG=magnetocardiography; OI=organization index.