DISCUSSION
The present study retrospectively
analyzed the characteristics of pseudo-focal ATs.
The main findings are as follows:
(1) the breakthrough site is close to a low-voltage area that contains
the collision site and masks a well-identified epicardial bundle
supporting the concealed part of the circuit; (2) a short PPI at the
site opposite to the breakthrough site demonstrates a macroreentrant
mechanism despite centrifugal propagation in the activation map; and (3)
the distinction from true focal ATs is crucial, since ablating the
breakthrough site is not the best therapeutic option in pseudo-focal
ATs.