| Abstract: | AAI pacing offers better hemodynamic characterstics than dual-chamber pacing and is the optimal mode for patents with sick sinus syndrome without AV conduction disorders. AAI pacing may be achieved by single-chamber atrial, by programming a dual-chamber pacemaker to the AAI mode, or by programming a dual-chamber pacemaker to DDD mode with a long AV delay. The annual incidence of AV block development in patients with sick sinus syndrome is low, probably 1-5%, but there is no method of detecting patients immune to future development of AV block. Chronotropic is often present in patients with sick sinus but the value of additional rate response is not yet established. Our recommendations for the choice of the method of pacing are discussed. |
