A new dual-chamber pacing mode to minimize ventricular pacing.
Despite the low long-term incidence of high-degree atrioventricular (AV) block and the known negative effects of ventricular pacing, programming of the AAI mode in patients with sinus node dysfunction (SND) remains exceptional. A new pacing mode was, therefore, designed to combine the advantages of AAI with the safety of DDD pacing. AAIsafeR behaves like the AAI mode in absence of AV block. First- and second-degree AV blocks are tolerated up to a predetermined, programmable limit, and conversion to DDD takes place in case of high-degree AV block. From DDD, the device may switch back to AAI, provided AV conduction has returned. The safety of AAIsafeR was examined in 43 recipients (70 +/- 12-year old, 24 men) of dual chamber pacemakers implanted for SND or paroxysmal AV block. All patients underwent 24-hour ambulatory electrocardiographic recordings before hospital discharge and at 1 month of follow-up with the AAIsafeR mode activated. No AAIsafeR-related adverse event was observed. At 1 month, the device was functioning in AAIsafeR in 28 patients (65%), and the mean rate of ventricular pacing was 0.2%+/- 0.4%. Appropriate switches to DDD occurred in 15 patients (35%) for frequent, unexpected AV block. AAIsafeR mode was safe and preserved ventricular function during paroxysmal AV block, while maintaining a very low rate of ventricular pacing. The performance of this new pacing mode in the prevention of atrial fibrillation will be examined in a large, controlled study.
Savouré
Arnaud
A
University Hospitals Rouen, France.
Fröhlig
Gerd
G
Galley
Daniel
D
Defaye
Pascal
P
Reuter
Sylvain
S
Mabo
Philippe
P
Sadoul
Nicolas
N
Amblard
Amel
A
Limousin
Marcel
M
Anselme
Frederic
F
D000368:Aged; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D005260:Female; D006352:Heart Ventricles; D006801:Humans; D008297:Male; D010138:Pacemaker, Artificial