Pulmonary vein activation in atrial fibrillation and sinus rhythm

The purpose of this study was to determine the relationship between pulmonary vein (PV) electrical activation during atrial fibrillation (AF) and after cardioversion into sinus rhythm.

Electrograms were recorded using a circular mapping catheter during AF and after cardioversion in 53 PVs from 41 patients. Two activation patterns were observed in AF. Group 1 had fixed, consistent, uniform activation sequences most (>70%) of the recording time. Group 2 had no fixed activation sequence. In Group 1, a constant single activation sequence pattern was seen in 22 PVs (Group 1a). The earliest PV activation sites were the same during AF and after cardioversion to sinus rhythm in 17 (77%) PVs from Group 1a. Fourteen of these 17 (82%) cases also had a common site of electrogram polarity reversal. In Group 2, a relationship between PV activation before and after cardioversion was not found. Segmental radio frequency (RF) ablation was performed during sinus rhythm after cardioversion. There was no difference in the number of atriovenous breakthroughs between the two groups (1.9+/-0.7 vs. 2.0+/-0.6 breakthroughs, P=NS). PV disconnection was achieved in all PVs with a mean RF duration of 13.5+/-4.5 min per vein in Group 1 and 14.0+/-4.9 min per vein in Group 2 (P=NS).

A uniform PV electrogram pattern recorded during AF usually predicts the activation sequence and/or the polarity reversal sites during sinus rhythm. This pattern does not necessarily suggest a single atriovenous breakthrough point.