Figure 3 . Representative examples of fully preexcited QRS complexes of accessory pathways ablated from the left side. Most lateral sites (LA, LAL, LL, LPL) are characterized by QS/rS in lead I and high amplitude V1, Contrariwise, septal/paraseptal sites (LP, LPS, LMS) have R/RS wave in lead I and often small amplitude/multiphasic QRS in V1. Lead aVF differentiates between superior (R) and inferior locations (QS/rS). Representative examples of fully preexcited QRS complexes of accessory pathways ablated from the right side are in Supplementary Figures 1 and 2. For abbreviations see text.