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Programming a fixed long atrioventricular delay is not effective in preventing ventricular pacing in patients with sick sinus syndrome.

J C Nielsen·A K Pedersen·P T Mortensen·H R Andersen
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Abstract

AIM: Most patients with sick sinus syndrome (SSS) and normal atrioventricular (AV) conduction receive dual chamber (DDDR) pacemakers. Programming a long AV delay has been proposed to avoid ventricular pacing. The present study aimed to evaluate ventricular stimulation in SSS patients with DDDR pacemakers with a long AV delay. METHODS AND RESULTS: Thirty eight patients treated with DDDR pacemakers with a fixed long AV delay (300 ms) were studied. Data from the pacemaker event recorder were retrieved after 3 months and every year after implantation. Ten patients underwent 24 h Holter recording. Mean follow-up was 11.9 +/- 8.3 months. Median daily number of paced events in the ventricle was 2659 (25th-75th percentiles: 775-21 315) with a large inter-individual variation. The proportion of paced events in the ventricle correlated weakly with the baseline PQ interval (Spearman's rho 0.331, P = 0.043). In 12/38 patients the mean daily number of paced events in the ventricle exceeded 10,000. During 24 h Holter recording, pacemaker arrhythmias caused by repetitive retrograde atrioventricular conduction, known as VA (ventriculoatrial) conduction, occurred in five out of 10 patients. CONCLUSION: DDDR pacing with a fixed long AV delay is inefficient in reducing ventricular pacing in one third of patients and is associated with a high risk of arrhythmias caused by repetitive retrograde AV conduction, and therefore cannot be recommended for general use in SSS patients.

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AgedAged, 80 and overArrhythmias, CardiacAtrioventricular NodeCardiac Pacing, ArtificialElectrocardiography, AmbulatoryElectrophysiologyFemaleFollow-Up StudiesHumansMaleRisk FactorsSick Sinus SyndromeTreatment OutcomeVentricular FunctionEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov't

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J C Nielsen, A K Pedersen, P T Mortensen, H R Andersen. 1999. Programming a fixed long atrioventricular delay is not effective in preventing ventricular pacing in patients with sick sinus syndrome.. https://doi.org/10.1053/eupc.1998.0026

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