Propagation Map Calculation and Data Export
Raw AcQMap electrode biopotential signals were visually inspected to
identify outlying or corrupted signals, which were then manually
excluded. A low pass filter at 100Hz as well as a 50Hz notch filter and
smoothing algorithm were applied followed by selection of a QRS-T wave
template for subtraction. Three consecutive 10-second mapping segments
were created for simultaneous timepoints in both the left and right
atria, confirmed relative to the coronary sinus low amplitude pacing
spike. This process was repeated to create two 30-second AF maps
following splicing together of each 10s segment. Propagation maps were
calculated using the default timing method (based on -dv/dt of dipole
signals), window width (for isochronal colour bars) of 80ms and time
threshold of 70ms (representing presumed minimum refractoriness).
AcQTrack propagation patterns were calculated for each segment and data
exported for offline analysis.