Radioelectrocardiography in diagnosis of rhythm disturbances in patients with implanted cardiac pacemakers.

The electrical pacemakers widely used in treat- ment of patients with impaired atrioventricular con- duction can under certain circumstances produce new disturbances of rhythm.Such disturbances may result from alteration of haemodynamic condi- tions (Sowton, 1965), improved blood supply, changes in myocardial threshold caused by prolonged artificial stimulation, or from a failure of pacemaker assembly (Furman et al., 1966).They may also be due to the technical properties of a particular type of pacemaker.Most of these arrhythmias become apparent soon after implantation of the pacemaker, but some do not show until the patient is fully active.The latter are difficult to detect with the electrocardiogram at rest.Radioelectrocardiography makes it possible to reveal them during physical activity.