Fig. 1

Example of the catheter setup during isoproterenol provocation test and examples of activation pattern of PACs. A Duodecapolar catheter with electrodes spanning from the SVC, right atrium/CT [blue] to the CS [green], ablation catheter in the right superior PV recording the far-field IAS [violet], 10-pole circular mapping catheter in the left superior PV recording the far-field LAA activity [red]. B Activation pattern during sinus rhythm. C Example of activation pattern PACs from the CS. The earliest activation (red star) is recorded in the dipole CS 7–8 of the distal segment of the duodecapolar catheter (inside the CS). D Example of activation pattern of PACs from the LAA. The earliest activation (red star) is recorded by the circular mapping catheter inside the left superior PV recording the far-field from the LAA. (Della Rocca, Di Biase et al. 2021)