In dual loop reentrant ATs, the differentiation of the active circuit
from the passive circuit in a dual loop reentry is still challenging. In
such complicated AT cases, entrainment pacing is useful for determining
the dominant circuit. However, we differentiated the active circuit by
an AT activation map with an adjustment of the lower threshold value in
the early meets late module. We also detected the gap of the previous
PVI line by the same map with a further adjustment of the lower
threshold value. The adjustment of the lower threshold might be
advantageous for differentiating an active circuit of a dual loop
reentry as well as gaps along the PVI line.