Prevention of Chronic Atrial Fibrillation by Pacing in the Region of Bachmann's Bundle: Results of a Multicenter Randomized Trial

Abstract
Atrial pacing locations that decrease atrial activation and recovery time may be preferable in patients with a history of atrial arrhythmias. This multicenter prospective randomized study compared the efficacy of Bachmann's bundle (BB) region pacing to right atrial appendage (RAA) pacing in patients with recurrent paroxysmal atrial fibrillation (AF). Patients with standard pacing indications (n = 120, 70+/-11 years) were randomized to atrial pacing in either the RAA (n = 57) or BB region (n = 63). Implantation time was similar between groups (88+/-36 min [n = 38] for BB vs 83+/-34 min [n = 34] for RAA). No differences in pacing threshold, impedance, or sensing between BB and RAA groups were observed at implantation or after the 6-week, 6-month, and 1-year follow-up periods. Average length of follow-up was 12.6+/-7.4 months for the BB group and 11.8+/-8.0 months for the RAA pacing group. The percentage of atrial pacing was similar between groups (61%+/-34% RAA vs 65%+/-31% BB at 2 weeks after implant). BB atrial pacing significantly (P < 0.05) shortened p wave duration compared with sinus rhythm (123+/-21 msec vs 132+/-21 msec, n = 50) 2 weeks after implant. In contrast, p wave duration was longer during atrial pacing from the RAA position compared with sinus rhythm (148+/-23 msec vs 123+/-23 msec, n = 37). Additionally, p wave duration was shorter during BB pacing than during RAA pacing. Patients with BB pacing had a higher (P < 0.05) rate of survival free from chronic AF (75%) compared with patients with RAA pacing (47%) at 1 year. BB region pacing is safe and effective for attenuating the progression of AF.