ABSTRACT
Pacemaker support for bradycardia has been a reality since the first human implant in 1958. Although syncope and bradycardia had been noted for hundreds of years, it was not until Stokes together with Adams, made the link between a slow pulse and syncope. There have been no large randomised trials of the effect of pacemakers on mortality associated with bradycardias and heart block. The exclusion of a reversible cause is paramount as long-term pacing is not indicated. The diagnosis of bradycardia, which may be persistent or intermittent, is confirmed by electrocardiogram (ECG). In order to diagnose the latter, a prolonged period of monitoring, either ambulatory or by implanted loop recorder, may be required. Pacemaker mode and function are described in shorthand using a four-letter coding. Originally, all pacemakers used a single pacing lead placed in the right ventricle. This type of pacemaker ignored any contribution of the atria and dual chamber pacemakers were developed to mimic the normal conduction of heart.
