Sick sinus syndrome and diffuse impairment of the conduction system in a child: successful pacing with a steroid eluting endocardial pacing lead.

A 9-year-old patient who had had a syncope was found to have atrial flutter in a resting electrocardiogram (ECG). Brief phases of sinus arrest had previously occurred after drug conversion to sinus rhythm. Structural heart disease was excluded by cardiac catheterization and angiography. Electrophysiologic study revealed a sick sinus syndrome, associated with diffuse impairment of the conduction system (supra-, infra-, and intrahisian block). Epimyocardial and an endocardial pacemaker implantation failed because of high stimulation threshold, after 3 years and 2 weeks, respectively. At the third implantation a steroid-eluting endocardial pacing lead was used and satisfactory pacing was still present 2 years later.