The use of atrial overdrive and ventricular rate stabilization pacing algorithms for the prevention and treatment of paroxysmal atrial fibrillation: the Pacemaker Atrial Fibrillation Suppression (PAFS) study.
OBJECTIVE
The PAFS study is a randomized, multicentre investigation of the effects of third generation anti-atrial fibrillation pacemaker algorithms in patients with paroxysmal atrial fibrillation (PAF).


RESULTS
182 patients (72 +/- 9 years, 55% male) with at least three symptomatic episodes of PAF within prior 3 months resistant to two anti-arrhythmics were enrolled. A pacemaker-derived atrial fibrillation (AF) burden of 1-50% was required in the initial induction phase. Seventy-nine patients fulfilled these criteria and were randomized to four, month-long phases in a crossover design. Algorithm phases were 'rate soothing' on, 'ventricular rate stabilization' on, and 'All on', which included these two algorithms plus post-AF response. The algorithm phases were compared to 'All off' dual chamber universal mode (DDD 60) for the analysis. Forty-two percent of patients enrolled in the monitoring phase had no AF. The percentage of AF induced by premature atrial contractions (PACs) was significantly reduced by rate soothing from 25 to 17% (P < 0.05). There was no significant change in AF burden, AF episode number, quality of life, or symptoms with any algorithm (P = ns).


CONCLUSIONS
The rate-soothing algorithm by atrial overdrive pacing reduced PAC-initiated PAF. However, there was no overall change in AF burden, PAF episodes, patient symptoms, or quality of life. Forty-two percent of PAF patients did not show any AF after enrollment, suggesting that bradycardia pacing alone eliminates AF.
Sulke
Neil
N
Cardiology Department, Eastbourne District General Hospital, East Sussex NHS Trust, Eastbourne, UK. neil.sulke@esht.nhs.uk
Silberbauer
John
J
Boodhoo
Lana
L
Freemantle
Nick
N
Kamalvand
Kayvan
K
O'Nunain
Sean
S
Hildick-Smith
David
D
Lloyd
Guy W
GW
Patel
Nikhil R
NR
Paul
Vince
V
D000368:Aged; D000465:Algorithms; D001281:Atrial Fibrillation / Q000503:physiopathology / Q000517:prevention & control* / Q000628:therapy*; D001919:Bradycardia; D002304:Cardiac Pacing, Artificial; D018592:Cross-Over Studies; D005260:Female; D006325:Heart Atria / Q000473:pathology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D013614:Tachycardia, Paroxysmal / Q000503:physiopathology / Q000517:prevention & control* / Q000628:therapy*; D016896:Treatment Outcome