Single lead VDD pacing in children: implantation and long-term follow-up

Abstract

VDD pacing using a single pass lead for complete heart block is well described in adults but there are few reports of its use in children. We have used 6 different standard adult size single pass leads and 5 different pacemaker generators in 21 children and adolescents aged 3.7–17.2 years (mean 9.9 years) and weighing 13.5 to 76 kg (mean 34.3 kg). Congenital complete heart block was present in 14 patients (with associated heart disease in 2 of them), surgical complete heart block in 6 patients and 2:1 AV block of uncertain cause in 1 patient. In 10 patients, the VDD system was their first pacing system. In 11 of the patients, 1–6 previous systems had been used and simultaneous extraction of ventricular leads (10) and/or atrial leads (5) was performed. All leads were introduced via a subclavian vein puncture (using the extraction sheath when present) and the atrial dipole was placed low in the right atrium to provide slack for further growth while maintaining atrial sensing. Ventricular thresholds ranged from 0.2 to 0.8 V. The minimal atrial amplitude was 0.7 to 4 mV and the maximum amplitude was 2.5 to 8 mV. There was one early micro-displacement and the lead was repositioned. Over a follow-up period of 2–64 months (mean 32 months), all but 1 of the patients have maintained low ventricular pacing thresholds and adequate atrial signals for reliable pacing at rest and with exercise. During this time some have undergone considerable growth. In 1 patient, atrial sensing was lost after cardiopulmonary bypass for additional cardiac surgery at 24 months and the pacemaker was programmed into VVIR mode. One patient with coexisting congenital heart disease died suddenly at 3 years but the pacing system had no fault at autopsy. The standard adult size single pass lead provides a simple means to enable reliable atrial synchronous ventricular pacing in growing children with complete heart block.