Long-term clinical performance of AAI pacing in patients with sick sinus syndrome: a comparison with dual-chamber pacing.
OBJECTIVE
In this clinical study, we compared two groups of age-matched patients, AAI and DDD, to evaluate the clinical benefits of AAI pacing in patients with sick sinus syndrome (SSS) and normal atrioventricular (AV) conduction.


RESULTS
Ninety-five patients with SSS implanted with AAI pacemakers were compared with 101 SSS patients implanted with DDD pacemakers. Mortality, chronic atrial fibrillation, lead survival rates, and reoperation rates were compared by Kaplan-Meier analysis. Eight AAI devices were switched to DDD due to high-degree (grade 2-3) AV block. The incidence of high-degree AV block was 1.104%/year, with a freedom rate of 88.6% at 10 years. There were no significant differences between the two groups in survival rates (87.8% in AAI vs. 93.4% in DDD at 10 years), freedom from atrial fibrillation (93.6% vs. 90.6%), or freedom from reoperation (71.3% vs. 76.3%). On the other hand, lead failure was twice as frequent in the DDD group than in the AAI group (relative risk=2.045, P=0.0382).


CONCLUSIONS
AAI pacing, a simple system using a single lead and single-chamber pacemaker, can achieve a clinical outcome similar to that of the DDD mode in patients with SSS and normal AV conduction.
Department of Cardio-thoracic Surgery, Nagoya University School of Medicine, 65 Turumai-cho, Syowa-ku, Nagoya City, Japan. hmasu@catvmics.ne.jp
Hiroshi
H
Masumoto
Yuichi
Y
Ueda
Rinya
R
Kato
Akihiko
A
Usui
Takashi
T
Maseki
Yasushi
Y
Takagi
Masato
M
Usui
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006325:Heart Atria / Q000503:physiopathology; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012086:Reoperation; D012804:Sick Sinus Syndrome / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome