Long-term effects of biatrial synchronous pacing to prevent drug-refractory atrial tachyarrhythmia: A nine-year experience

Biatrial Pacing for Atrial Tachyarrhythmia Prevention. Introduction: Result s of previous studies suggest that atrial resynchronization by multisite at rial pacing may contribute to prevention of recurrences in patients with dr ug-refractory atrial tachyarrhythmias and significant intra-atrial conducti on delay. Methods and Results: To verify this hypothesis, a prospective noncontrolled study of 86 patients (mean age 66 +/- 10 years) was conducted in a single center between January 1989 and February 1998, Inclusion criteria were P wa ve duration greater than or equal to 120 msec with interatrial conduction t ime greater than or equal to 100 msec, and history of multiple recurrences of atrial tachyarrhythmias (mean 7 +/- 4.8 episodes) evolving in a persiste nt mode for at least 6 months despite optimized drug treatment (mean 2.7 +/ - 1.8 drugs/patient), Patients were chronically implanted with a pacing sys tem that ensured permanent biatrial pacing using two atrial leads, one plac ed in the high right atrium and the other one into the mid or the distal pa rt of the coronary sinus. P wave duration decreased from a mean value of 18 7 +/- 29 msec before implant to 106 +/- 14 msec (P < 0.0001) under biatrial pacing. After a 33-month mean follow-up (range 6 to 109), 55 patients (64% ) remained in sinus rhythm, including 28 patients (32.6%) without any docum ented recurrence and 27 patients with one or more recurrences in a paroxysm al or in a persistent form. In these 55 patients, drug treatment was signif icantly reduced in relation to the preimplantation period (1.4 +/- 0.6 vs 1 .7 +/- 0.5 drugs/patient; P = 0.011), The other 31 patients went into chron ic atrial arrhythmia after a mean period of 26 months. The only predictive factor of positive response was a spontaneous P wave duration <160 msec at baseline. Conclusion: The results are consistent with a preventive effect of permanen t biatrial pacing on recurrent and drug-refractory atrial arrhythmias assoc iated with intra-atrial conduction delay.