In the first procedure, we performed PV isolation, SVC isolation, and CTI ablation. However, AF persisted and immediately recurred soon after electric cardioversion. Therefore we performed GP ablation around PVs (posterior Left GP, anterior right GP, and superior left GP) and linear ablation between the superior PVs (i.e., roofline). The ATP challenge was performed during ongoing AF and not repeated after the restoration of sinus rhythm. In the second procedure, we performed re-isolation of the reconnected right PV and SVC.
Isoproterenol infusion induced frequent PACs from multiple foci (white arrows in the left and middle panel). ATP injection induced AF from multiple foci (white arrows in the right panel) without dormant conduction of the isolated veins. We identified the trigger foci in the distal portion of CS and the left PV and LA appendage ridge. Radiofrequency ablation along the ligament of Marshall and lateral aspect of the mitral annulus (opposed to the distal CS) suppressed these PACs.
A bolus administration of ATP still induced AF. The first beat initiating AF was documented at the CS ostium and RA septum (white arrows).
C . Therefore, we performed HFS within the CS and RA septum. Vagal responses by HFS were observed at three sites in the RA septum adjacent to the interatrial groove and two sites near the CS ostium (blue tags in the right panels). Following the RF ablation at these sites, AF was no longer inducible by ATP provocation.
TA = tricuspid annulus. Other abbreviations are the same as Figure 1 and 2.