Localization of Atrial Fibrillation Triggers in Patients Undergoing Pulmonary Vein Isolation Importance of the Carina Region

Objectives This study sought to identify the origin within the pulmonary vein (PV) of reproducible atrial fibrillation (AF) triggers. Background Triggers for AF frequently originate from PVs. However, a systematic evaluation of the location of origin within the PV orifice and associated techniques for eliciting triggers has not been performed. Methods Spontaneous triggers and those provoked with isoproterenol (up to 20 mu g/min) and/or cardioversion in 45 patients with AF were identified using multipolar catheter recordings. In identifying origin, PVs were divided into 17 equal segments from ipsilateral PVs with "carina zone" (CZ) (7 segments between the PVs) and 10 "noncarina zone" (NCZ) segments. Results Sixty-three reproducible triggers were noted in 37 of the 45 (82%) patients with 57 from PV and 6 (10%) from non-PV sites. Although triggers were identified from 26 of 34 distinct PV segments, most PV triggers (36, 63%) originated from CZ segments (p < 0.05) from both right (17 triggers) and left (19 triggers) PVs. The CZ triggers were more often spontaneous (11 of 36 in CZ vs. 2 of 21 in NCZ; p < 0.05) or elicited with CV (17 of 36 in CZ vs. 6 of 21 in NCZ; p < 0.05). In contrast, NCZ triggers were more likely to require isoproterenol to be provoked (13 of 21 [62%] vs. 8 of 36 [22%], p < 0.05). Conclusions Reproducible spontaneous and provoked PV triggers initiating AF can be observed in most patients undergoing AF ablation. These triggers most commonly originate from the carina region of both right and left PVs. Noncarina PV triggers more commonly require provocation with isoproterenol infusion. (J Am Coll Cardiol 2008; 52: 1413 -20) c 2008 by the American College of Cardiology Foundation