Device treatment of atrial tachycardia--minor additional effect of repeating pacing sequences.
OBJECTIVE
Ramp and burst pacing as treatment for atrial tachycardia (AT), one known trigger mechanism of atrial fibrillation (AF) are available in permanent pacemakers to reduce the burden of AF. An analysis of the success rate of three consecutive antitachycardia pacing sequences is presented.


METHODS
The AT 500 (Medtronic) pacemaker was implanted in 36 patients (18 female, mean age 77+/-11 years) with pacemaker indication due to tachybrady arrhythmias (n=34), and other indications (n=2). A standardized AT treatment of 8 sequences of ramp followed by six and four sequences burst pacing was programmed on after 1 month of tachycardia detection only. 5 consecutive sinus beats or 3 min with atrial rhythm not classified as AF or AT defined treatment success and was registered at 3 months follow-up.


RESULTS
2979 episodes (mean 85+/-316) in 17 patients (7 female) were treated and analyzed. The overall treatment success increased from 42+/-27% to 44+/-31% and 45+/-31% during the consecutive ATP sequences (ns). The average ATP success of the first ramp pacing sequences was 95+/-10%, the second ramp ATP sequence was successful in 3+/-6%, and the last ramp ATP sequence in 2+/-5%.


CONCLUSIONS
95% of the 45% treatment success of a standard AT treatment was achieved by the first ramp pacing sequence. Further antitachycardia pacing sequences did not increase the success rate significantly.
Schuster
Peter
P
Institute of Medicine, Department of Heart Disease, University of Bergen and Haukeland University Hospital, N-5021 Bergen, Norway. peter.schuster@med.uib.no
Faerestrand
Svein
S
Ohm
Ole-Jørgen
OJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000628:therapy; D002304:Cardiac Pacing, Artificial; D004867:Equipment Design; D004869:Equipment Safety; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D012107:Research Design; D013318:Stroke Volume; D013612:Tachycardia, Ectopic Atrial / Q000503:physiopathology / Q000628:therapy*; D016896:Treatment Outcome
D000889:Anti-Arrhythmia Agents