Localization of arrhythmogenic triggers of atrial fibrillation

Mapping procedures to identify triggers of atrial fibrillation from pulmonary veins (PVs) are not well established. We sought to determine the value of multipolar recordings from the coronary sinus (CS) and crista terminalis (CT) for identifying the origin of paced and atrial premature depolarizations (APDs) initiating atrial fibrillation from left versus right PVs.

Fifteen patients with paroxysmal atrial fibrillation refractory to medications had decapolar catheters (5-mm electrode, 2-mm interelectrode spacing) placed in the CS and posterior medial to the CT. Bipolar electrograms were recorded at each site. Electroanatomic left atrial endocardial maps were created in sinus rhythm, and each PV was identified and paced. During spontaneous APDs initiating atrial fibrillation and PV pace maps, the atrial activation and the earliest electrogram at CS and CT were compared. PV sites were designated as sites of origin of APDs when (1) intracardiac electrograms in the CS and CT during arrhythmogenic APDs matched those of PV pace maps, (2) local activation preceded CS and CT recordings by at least 40 msec (all sites), and (3) atrial depolarizations were eliminated by application of radiofrequency energy (24/26 sites). Pacing from each of the 30 right PV sites resulted in proximal to distal CS activation and later recordings at the CS than the CT (earliest CS-CT activation range: -15 to -58 msec, mean -32 +/- 12). In contrast, pacing from the left PV sites typically (28/30 sites) activated the CS from the distal to proximal poles and demonstrated simultaneous or earlier (CS-CT range: -14 to +54 msec, mean 13 +/- 17) recordings of the CS than the CT (P < 0.0001). For 13 APDs mapped to the right PVs, CS minus CT activation was -17 to -49 msec (mean -31 +/- 8). For 13 APDs localized to the left PVs, the CS minus CT activation time ranged from -8 to +28 msec (mean 14 +/- 15).

Activation sequence mapping from multipolar catheters placed in the CS and along the posterior medial CT rapidly differentiates right and left PV sites of origin of atrial depolarization.