Three-year follow-up of atrial sensing efficacy in children and adults with a single lead VDD pacing system

The purpose of this study was to evaluate the efficacy of atrial sensing in children with a single pass lead VDD pacing system and to compare it with the efficacy of atrial sensing in adult patients with the same pacing system. Although the feasibility of single pass leed VDD pacing system implantation in children was recently demonstrated, the efficacy of atrial sensing remains unclear. In addition, the effect of accelerated growth of children on the systems' efficacy has not been addressed. Atrial sensing followed by ventricular sensing and atrial sensing follow ed by ventricular pacing was prospectively evaluated in 13 children (age 0.5-15 years) and 24 adult patients (age 19-74 years). All had the same endocardial pacing system using a single pass lead. The children and adults had effective atrial sensing at a success rate of 94.00 +/- 9.687% and 96.04 +/- 4.64%, respectively during mean follow-up of 3.5 years. The atrial electrogram amplitude was similar in both groups, 1.8 +/- 1.5 mV in children and 1.8 +/- 1.1 mV in adults. The adult patients more frequently exhibited ventricular sensing following atrial sensing. The ventricular pacing threshold and impedance were stable in both groups. When necessary, in children, the atrial sensing was corrected by adjusting the peacemaker's lower rate programming. Highly effective atrial sensing was demonstrated in children and adult patients with a single pass lead VDD pacing system. During a mean follow-up of 3.5 years, not only was the atrial electrogram amplitude stable, but the clinically relevant atrial sensing was highly effective, justifying endocardial pacing with single pass lead VDD pacing in children and adults with preserved sinus node function.